JP5715789B2 - Combined heat source machine - Google Patents

Description

  The present invention relates to a composite heat source apparatus including a plurality of combustion units including a burner and a heat exchanger.

  A heat source machine in which a burner and a heat exchanger are provided in a can body is known. In this heat source machine, a combustion fan provided below the burner is rotated, and fuel gas (or fuel spray or the like) is burned by supplying combustion primary air and secondary air to the burner. The combustion gas generated by the combustion in the burner is guided to a heat exchanger provided above the burner, thereby warming the liquid (water or hot water) passing through the heat exchanger. The combustion gas whose temperature has been lowered by warming the liquid with the heat exchanger is discharged to the outside of the can body from an exhaust hood provided above the heat exchanger.

  There is also known a composite heat source machine in which a plurality of (for example, two) cans are mounted and a burner and a heat exchanger are provided in each can. Hereinafter, the burner and the heat exchanger provided for the burner, including the space between them, may be referred to as a “combustion unit”. In addition, the space between the burner and the heat exchanger may be referred to as a “combustion chamber”. In this composite heat source machine, a combustion fan is provided for each combustion unit, and a plurality of liquids (for example, hot water for hot water supply and hot water for bath) can be simultaneously heated.

  The heat exchangers of these heat source machines are provided with densely packed metal fins along the path of the combustion gas, and the combustion gas passes between the fins to make the liquid in the heat exchanger efficient. It is designed to warm up well. In addition, depending on the use over a long period of time, soot and dust may accumulate between the fins, and a phenomenon in which combustion gas does not easily pass through the fins (so-called fin clogging) may occur. When fin clogging occurs, incomplete combustion may occur as a result of insufficient supply of combustion air due to increased passage resistance of the combustion gas. Therefore, the occurrence of incomplete combustion is avoided by increasing the rotational speed of the combustion fan to increase the supply amount of air (for example, Patent Document 1).

  Furthermore, in recent years, a single can type combined heat source apparatus in which a plurality of (for example, two) combustion units are configured in a single can has been proposed. In this single can type combined heat source machine, the inside of a single can body is partitioned into a plurality of sections by partition walls, and a plurality of combustion units are configured by mounting a burner and a heat exchanger in each section. Further, by adopting a configuration in which air is supplied from one combustion fan to the plurality of combustion units (a configuration in which one combustion fan is shared by the plurality of combustion units), the heat source machine can be reduced in size. It becomes possible (Patent Document 2).

JP 2003-028417 A JP 2009-264675 A

  However, a composite heat source machine of a type in which a plurality of combustion units share one combustion fan has a problem that it is difficult to cope with fin clogging generated in the heat exchanger. That is, since the air from the combustion fan is supplied to a plurality of (for example, two) combustion units at the same time, when the fin clogging of the heat exchanger occurs in one combustion unit, the amount of air supplied to the combustion unit is simply Not only decreases, but also increases the amount of air to other combustion units. Therefore, if the rotation speed of the combustion fan is increased just because fin clogging has occurred in a certain combustion unit, there is a risk that the amount of air to other combustion units will become excessive, and the normal combustion state cannot be maintained. Arise. In addition, such a phenomenon is not limited to a composite heat source machine in which a plurality of combustion units are provided in a single can, and any composite heat source machine may be used as long as a single combustion fan is shared by a plurality of combustion units. Can also occur.

  The present invention provides a composite heat source unit that can share a single combustion fan in a plurality of combustion chambers, and can maintain a good combustion state even when fin clogging of a heat exchanger occurs. With the goal.

In order to solve the above-described problems, the composite heat source machine of the present invention employs the following configuration. That is,
A plurality of combustion units provided with a burner and a heat exchanger are provided, the combustion fan is rotated, and the combustion air is simultaneously supplied to the plurality of combustion units sharing the combustion fan. In a composite heat source machine that performs a combustion operation of a combustion unit supplied with fuel by supplying fuel to at least one burner,
Index acquisition for acquiring an index related to clogging of the fins of the heat exchanger for a combustion unit that is operating independently during single operation where a single combustion unit is performing combustion operation among the plurality of combustion units Means,
When obtaining an index related to the fin clogging, an index storage means for storing the index for each combustion unit;
Rotational speed correction means for correcting the rotational speed of the combustion fan based on the index for the combustion units that are operating simultaneously when two or more of the combustion units are operating simultaneously. It equipped with a door,
The rotational speed correction means is within an allowable amount determined according to an index of the one where the fin clogging is not progressing among the plurality of indices stored for the combustion units that are operating simultaneously. A correction amount determining means for determining a correction amount of the rotation speed based on an index of the one where the fin clogging is progressing;
The rotational speed of the combustion fan is corrected according to the correction amount determined by the correction amount determination means .

In the composite heat source apparatus of the present invention having such a configuration, the fins of the heat exchanger provided in the combustion unit are clogged while one of the plurality of combustion units is operating independently. Get an indicator. Here, as an index related to the clogging of the fins, for example, the passage resistance can be detected based on the pressure difference before and after the heat exchanger, but the temperature of the combustion gas or the inner wall of the combustion chamber heated by the combustion gas And the like, and an index relating to fin clogging can be obtained based on the detection results. The index thus obtained is stored for each combustion unit. When two or more combustion units sharing a combustion fan among a plurality of combustion units burn simultaneously, an index related to fin clogging stored for each combustion unit with respect to the combustion units burning simultaneously Based on the above, the rotational speed of the combustion fan is corrected. When determining the correction amount of the rotational speed, first, for the combustion unit that is operating simultaneously, an index relating to fin clogging that is acquired and stored for each combustion unit during the individual operation is acquired. Then, the correction amount is determined based on the index of the fin clogging that is within an allowable amount determined according to the index of the index that has not progressed the fin clogging. At this time, first, an allowable range is obtained based on the index that is not progressing with fin clogging, and then the correction amount is determined based on the index that is progressing with fin clogging. Or, conversely, the correction amount is first calculated based on the index of the one where the fin clogging is progressing, and then the correction amount is set so as to be within the allowable range according to the index of the one where the fin clogging is not progressing. Correct it. When correcting the rotational speed of the combustion fan, it is only necessary to consider the index for the combustion unit that is burning simultaneously among the plurality of combustion units that share the combustion fan. It is not necessary to consider this index.

When two or more combustion units that share a combustion fan are burnt simultaneously, if there is a difference in the degree of fin clogging between the combustion units, the combustion unit that has not advanced fin clogging will have combustion air. Is supplied in excess. For this reason, if the rotational speed of the combustion fan is corrected in accordance with the direction in which the fin clogging progresses, air is supplied excessively in the combustion unit in which the fin clogging does not progress, and a good combustion state is obtained. It becomes difficult to maintain. However, if the rotational speed of the combustion fan is not corrected, it becomes difficult to maintain a good combustion state in which the fin clogging has progressed. On the other hand, if the rotational speed of the combustion fan is corrected in consideration of the index related to the fin clogging acquired in advance for the combustion unit to be simultaneously burned, such as the composite heat source machine of the present invention, the fin clogging will occur. The rotational speed of the combustion fan can be corrected so that the combustion state in which the fin clogging has advanced can be improved within the range in which the combustion state in the forward direction is not impaired. For this reason, even when two or more combustion units sharing a combustion fan are simultaneously burned, it is possible to maintain a good combustion state. In addition, a combustion unit that performs simultaneous combustion can realize a good combustion state regardless of the degree of fin clogging by simply setting an allowable correction amount and a correction amount according to an index related to fin clogging. As described above, the rotational speed of the combustion fan can be corrected.

  The composite heat source machine of the present invention described above can also be a composite heat source machine having the following configuration. First, the inside of a single can body is divided into a plurality of sections using partition walls, and a combustion unit is mounted in each section. Further, the partition wall is formed in a hollow structure in which two plate members are arranged with a gap therebetween, and air from the combustion fan passes through the gap. Furthermore, it can be set as the composite heat source machine by which the temperature detection part was inserted between the two board | plate materials which comprise a partition wall in the state which the temperature sensitive part did not contact with respect to the board | plate material. In the composite heat source machine having such a configuration, an index related to fin clogging may be acquired based on a result of comparing the detected temperature detected by the temperature detecting unit with a predetermined threshold temperature.

  If the inside of a single can body is partitioned into a plurality of partitions by partition walls and a combustion unit is mounted in each partition, there is only one can body even though a plurality of combustion units are mounted. Good. For this reason, combined with the fact that the combustion fan is shared by a plurality of combustion units, the combined heat source machine can be greatly reduced in size. Further, since the inside of the partition wall is cooled by the air from the combustion fan, the heat resistance of the partition wall can be ensured. With such a configuration, if the temperature detection unit is inserted so that the temperature sensing unit is not in contact with the plate material constituting the partition wall, any of the combustion units mounted on both sides of the partition wall can be used. Even when fin clogging occurs, it can be detected using the temperature detection unit. For this reason, since it is not necessary to provide a temperature detection part for every combustion unit, the number of parts of a composite heat source machine can be reduced. Moreover, since the temperature detection part is inserted inside the partition wall and is not directly exposed to the combustion gas, it is not necessary to use a temperature detection part that is particularly excellent in heat resistance. In addition, the temperature sensing part of the temperature detection part is provided in a non-contact manner with respect to the plate material constituting the partition wall, and is only indirectly heated by the radiant heat from the plate material. For this reason, compared with the case where the temperature sensing part is exposed to the combustion gas, it is less susceptible to the influence of the disturbance, and it is possible to stably and accurately obtain an index related to clogging of the fins.

  In the composite heat source machine of the present invention having such a configuration, an index related to clogging of fins may be acquired as follows. That is, when switching from a state in which two or more combustion units are operating simultaneously to a state in which one combustion unit is operating independently, the temperature detected by the temperature detector decreases with time. Therefore, an index related to clogging of the fins may be acquired by comparing the temperature detected by the temperature detection unit with a predetermined threshold temperature that decreases with time.

  By doing so, it is possible to obtain an index related to clogging of the fins even in a state before the temperature detected by the temperature detecting unit is stabilized (here, a state where the temperature is decreasing with time). As described above, since the temperature sensing portion of the temperature detection portion is provided in a non-contact manner with respect to the partition wall plate material, the temperature can be stably and accurately detected without being affected by disturbance. For this reason, it is possible to acquire an accurate index regarding fin clogging even in a state where the detected temperature is decreasing.

  Alternatively, in the composite heat source machine of the present invention having the above-described configuration, an index relating to fin clogging may be acquired as follows. In other words, when the single operation is started in a state where the temperature detected by the temperature detection unit is lower than the predetermined reference temperature, and the detected temperature exceeds the reference temperature after that, within the predetermined time after the reference temperature is exceeded. You may make it acquire the parameter | index regarding fin clogging based on the raise rate of detected temperature.

  By doing so, it is possible to obtain an index related to clogging of the fins even in a state before the temperature detected by the temperature detecting unit is stabilized (here, a state where the temperature is rising as time elapses). As described above, since the detected temperature of the temperature detecting unit is not easily affected by disturbance, an accurate index regarding fin clogging can be acquired even in a state where the detected temperature is rising.

It is sectional drawing which showed the rough structure of the composite heat source machine 10 of a present Example. It is sectional drawing which showed the structure of the unit burner 2a. FIG. 3 is a cross-sectional view showing the structure of a partition wall 8 provided inside the can body 1. It is explanatory drawing which showed the state to which the temperature sensor 11 was attached. It is explanatory drawing which showed the principle which the composite heat source machine 10 of a present Example detects the presence or absence of generation | occurrence | production of fin clogging. It is explanatory drawing which showed the result of having measured the change of the detected temperature by the temperature sensor 11, varying the degree of fin clogging. It is the flowchart which showed the outline | summary of the control performed in order to correct | amend the rotational speed of the combustion fan 6 during the simultaneous combustion of the 1st burner 2-1 and the 2nd burner 2-2. It is a flowchart of a hot water supply side rank acquisition process. It is a flowchart which shows the fan rotational speed correction process of 1st Example. It is explanatory drawing which showed the correction table referred when determining the correction amount of the rotational speed of the combustion fan. It is explanatory drawing which showed a mode that the correction amount with respect to a hot water supply side rank value and a bath side rank value was determined. It is explanatory drawing which showed a mode that the increase amount of the rotational speed of the combustion fan 6 was determined when the hot water supply side and the bath side are clogged with fins. It is a flowchart which shows the fan rotational speed correction process of 2nd Example. It is explanatory drawing which showed a mode that the candidate value of the correction amount of rotational speed was set corresponding to the larger rank value. It is explanatory drawing which showed a mode that the allowable value of the corrected amount of rotational speed was set corresponding to the smaller rank value. It is explanatory drawing which showed the principle which detects a rank value based on the temperature change at the time of switching from simultaneous operation to independent operation. It is the flowchart which showed the hot water supply side rank acquisition process in a 1st modification. It is explanatory drawing which illustrated the approximate expression of the threshold temperature for rank-up, and the approximate expression of the threshold temperature for rank-down. It is explanatory drawing which showed the principle which acquires a rank value in a 2nd modification. It is explanatory drawing which illustrated the composite heat source machine 10 which has a some can body.

Hereinafter, in order to clarify the contents of the present invention described above, examples will be described in the following order.
A. Combined heat source structure:
B. Fin clogging detection principle:
C. Overview of combustion fan rotation speed correction during simultaneous operation:
C-1. Obtaining hot water side rank and bath side rank:
C-2. Fan rotational speed correction processing of the first embodiment:
C-3. Fan rotation speed correction processing of the second embodiment:
D. Variation:
D-1. First modification:
D-2. Second modification:
D-3. Third modification:

A. Combined heat source machine structure:
FIG. 1 is a cross-sectional view showing a rough structure of a composite heat source machine 10 of the present embodiment. In the illustrated composite heat source apparatus 10, the inside of the can 1 is divided into two regions by a partition wall 8, and a burner and a heat exchanger described later are mounted in each region. For example, an area displayed on the right side of the sheet of FIG. 1 (hereinafter sometimes referred to as “first area”) will be described. A first burner 2-1 is mounted below the first area on the right side. The first heat exchanger 3-1 is mounted on the upper part of the first region, and the first combustion chamber 7-1 is provided between the first burner 2-1 and the first heat exchanger 3-1. Is formed.

  The first burner 2-1 has a plurality of unit burners 2a that are elongated in the front-rear direction of the can 1 (the direction orthogonal to the paper surface of FIG. 1). A plurality are arranged in a direction (a direction parallel to the paper surface of FIG. 1). In addition, the first heat exchanger 3-1 includes a plurality of heat absorbing fins 3a stacked with gaps in the front-rear direction of the can body 1, heat absorbing tubes 3b meandering through the heat absorbing fins 3a, and the heat absorbing fins 3a. It is formed by a sealing plate 3c for sealing the end portion. A water supply pipe (not shown) is connected to the upstream side of the heat absorption pipe 3b of the first heat exchanger 3-1, and a hot water supply pipe (not shown) is connected to the downstream side of the heat absorption pipe 3b. Then, when the hot water tap provided at the downstream end of the hot water pipe is opened and water is passed through the first heat exchanger 3-1, the first burner 2-1 is ignited, and hot water at a set temperature is discharged from the hot water tap. It has become so.

  Similarly, the second burner 2-2 is mounted below the second area in the area displayed on the left side of the page of FIG. 1 (hereinafter sometimes referred to as “second area”). A second heat exchanger 3-2 is mounted on the upper part of the two regions, and a second combustion chamber 7-2 is formed between the second burner 2-2 and the second heat exchanger 3-2. Yes. The second burner 2-2 is composed of a plurality of unit burners 2a, and the second heat exchanger 3-2 is formed of a plurality of stacked heat absorbing fins 3a, meandering heat absorbing tubes 3b, a sealing plate 3c, and the like. ing. Further, a return pipe (not shown) is connected to the upstream side of the heat absorption pipe 3b of the second heat exchanger 3-2, and a forward pipe (not shown) is connected to the downstream side of the heat absorption pipe 3b. When a circulation pump (not shown) is activated, hot water in the bathtub is pumped up and ignited in the second burner 2-2, and the hot water heated in the second heat exchanger 3-2 is returned to the bathtub. ing. In addition, since the hot water supply is required to have a larger heating capacity than the bath, the first burner 2-1 for hot water supply is configured rather than the number of unit burners 2a constituting the second burner 2-2 for bath. The number of unit burners 2a is larger.

  The lower portion of the can 1 is partitioned by a distribution plate 4 to form an air supply chamber 5, and the distribution plate 4 has a number of distribution holes 4 a formed therein. Then, when the combustion fan 6 connected to the air supply chamber 5 is rotated, the air from the combustion fan 6 flows into the air supply chamber 5 and is firstly supplied as combustion air through the distribution holes 4 a of the distribution plate 4. It is supplied to the burner 2-1 and the second burner 2-2. And the combustion gas of the 1st burner 2-1 is guide | induced to the 1st heat exchanger 3-1 through the 1st combustion chamber 7-1, and the heat absorption fin 3a provided in the 1st heat exchanger 3-1 is carried out. When passing between, the hot water in the endothermic tube 3b is warmed. Similarly, the combustion gas of the second burner 2-2 is led to the second heat exchanger 3-2 via the second combustion chamber 7-2, and the heat absorbing fins 3a provided in the second heat exchanger 3-2. When passing through, the bath water in the endothermic tube 3b is warmed. Then, it passes through the common exhaust hood 9 provided above the first heat exchanger 3-1 and the second heat exchanger 3-2 and is discharged from the exhaust port 9 a to the outside of the can 1.

  The composite heat source unit 10 is also equipped with a controller 12 for controlling the supply and ignition of the fuel gas to the first burner 2-1 or the second burner 2-2, the operation of the circulation pump for the bathtub, and the like. . As will be described later in detail, a signal from a temperature sensor 11 described later is input to the controller 12, and the rotational speed of the combustion fan 6 is controlled based on the result.

  FIG. 2 is an explanatory diagram showing the structure of the unit burner 2a by taking a cross-section at the PP position in FIG. As shown in the drawing, a mixing tube portion 2b extending in the forward direction of the can 1 (leftward on the paper surface of FIG. 2) is provided below the unit burner 2a. A distribution plate 4 is provided below the mixing tube portion 2 b, and the front portion of the distribution plate 4 is bent upward to form a rising portion 5 a at the front portion of the air supply chamber 5. . The front side of the rising portion 5a is closed by a gas manifold 2c, the gas manifold 2c is provided with a plurality of gas nozzles 2d, and a circular opening is formed in the rising portion 5a at a position facing the gas nozzle 2d. Is provided. An inflow end opened in a trumpet shape of the mixing tube portion 2b is provided so as to face the opening. Therefore, as shown by the dashed arrows in the figure, when fuel gas is injected from the gas nozzle 2d, it flows into the mixing tube portion 2b together with the primary air for combustion in the rising portion 5a, and is mixed in the mixing tube portion 2b. Is supplied to the unit burner 2a.

  FIG. 3 is a cross-sectional view showing the structure of the partition wall 8 provided inside the can 1. As shown in the drawing, the partition wall 8 has a hollow structure in which an intermediate partition plate 83 is provided between two wall plates 81 with a gap therebetween. Among these, the wall plate 81 is formed with a shoulder portion 81a formed by bending outward at a height equivalent to the upper end of the unit burner 2a, and a hanging plate portion 81b extending downward from the outer edge of the shoulder portion 81a. Has been. Therefore, the gap between the two wall plates 81 is wide at the drooping plate portion 81b. The widened portion communicates with the air supply chamber 5 through a communication hole 4 a formed in the distribution plate 4. A plurality of air blowing holes 82 are formed in the shoulder portions 81 a of the wall plates 81. Further, a bent portion 81c formed by bending inward is formed at the upper end of the wall plate 81, and is joined so that the upper end of the partition plate 83 is sandwiched between the end portions of the bent portion 81c. In addition, a plurality of vent holes 84 are formed in the bent portion 81c.

  For this reason, when the combustion fan 6 is rotated, a relatively large amount of air is supplied to the gap between the two hanging plate portions 81b through the air supply chamber 5, and a part of this air is provided in the shoulder portion 81a. The air is blown upward along the outer surface of the wall plate 81 from the air blowing hole 82, and the remaining air passes through the gap between the wall plate 81 and the partition plate 83 and passes through the vent hole 84 formed at the upper end. Flows out. As a result, the outer side of the wall plate 81 is cooled by the air blown out from the air blowing holes 82, and the inner side is cooled by the air flowing through the gap with the intermediate partition plate 83, thereby ensuring the heat resistance of the partition wall 8. It becomes possible.

  Further, as shown in FIG. 3, the temperature sensor 11 is inserted between the two wall plates 81. And the bulging part 85 which bulges outside is formed in the part in which the temperature sensor 11 of the wall plate 81 is inserted. And the temperature sensor 11 is inserted in the state which does not contact the wall board 81 by forming the bulging part 85. FIG.

  FIG. 4 is an explanatory diagram showing a state in which the temperature sensor 11 is attached by taking a cross section at the QQ position in FIG. 1. The temperature sensor 11 has a temperature sensing part 11a formed by incorporating a temperature sensing element such as a thermistor or a thermocouple at the tip of a pipe-shaped sensor body 11c, and a flange-like fixing part 11b on the tail end side. Is formed. Further, a lead wire 11d connected to the temperature sensitive element is drawn out from the fixing portion 11b. This lead wire 11 d is connected to the controller 12.

  And if the sensor main body 11c is inserted until the fixing | fixed part 11b of the temperature sensor 11 contact | abuts the front surface of the can 1, the temperature sensing part 11a will be inserted to the substantially center position of the front-back direction of the partition wall 8. FIG. Further, the bulging portion 85 is also formed at the position where the temperature sensing portion 11a is inserted. For this reason, it is possible to install the temperature sensing part 11a so as not to contact the two wall plates 81, 81. If the temperature sensor 11 is not in contact with both wall plates 81 and 81 over its entire length, the temperature sensor 11 is fixed only by the fixing portion 11b at the tail end. Variations occur in the position of the temperature sensing part 11a. In view of this, the bulging portion 85 that is elongated along the insertion direction from the portion of the wall plate 81 where the temperature sensor 11 is inserted has a flat clamping portion 86 in the middle portion (the front side of the temperature sensing portion 11a). The temperature sensor 11 is positioned such that the sensor body 11c is sandwiched from both sides by the clamping portion 86.

  In the composite heat source apparatus 10 having the above-described configuration, the combustion gas generated by the first burner 2-1 passes between the heat absorption fins 3a of the first heat exchanger 3-1, and is then discharged by the second burner 2-2. The generated combustion gas passes between the heat absorption fins 3a of the second heat exchanger 3-2. While the composite heat source device 10 is used for a long period of time, soot and dust may accumulate between the heat-absorbing fins 3a, and “fin clogging” that makes it difficult for combustion gas to pass through may occur. When fin clogging occurs, the amount of combustion air supplied from the combustion fan 6 is reduced by the amount that makes it difficult for the combustion gas to pass, and the ratio of air to fuel gas (so-called air-fuel ratio) is from the optimum ratio at the time of design. It will shift. As a result, the normal combustion state may not be maintained. Therefore, in the composite heat source apparatus 10 of the present embodiment, whether or not fin clogging has occurred in the first heat exchanger 3-1 or the second heat exchanger 3-2 is detected by the following method. .

B. Fin clogging detection principle:
FIG. 5 is an explanatory diagram illustrating the principle by which the composite heat source apparatus 10 according to the present embodiment detects the presence or absence of fin clogging in the first heat exchanger 3-1 or the second heat exchanger 3-2. In FIG. 5, a part of the cross section of the composite heat source apparatus 10 is shown enlarged. When no fin clogging has occurred, the combustion gas generated by the combustion in the unit burner 2a is directed upward between the heat-absorbing fins 3a, as indicated by broken arrows in FIG. Pass through. On the other hand, if fin clogging occurs in a part of the endothermic fin 3a, it becomes difficult for the combustion gas to pass through the portion, so that the combustion gas passes through the portion where the fin clogging has occurred. In FIG. 5 (b), a portion where fin clogging has occurred is indicated by hatching, and the flow of combustion gas is indicated by a dashed arrow.

  When fin clogging occurs in the first heat exchanger 3-1 or the second heat exchanger 3-2 in this way, the combustion gas flows biased toward the partition wall 8. In addition, since the passage resistance in the heat exchanger (the first heat exchanger 3-1 or the second heat exchanger 3-2) increases, the amount of air supplied from the combustion fan 6 decreases, and the combustion gas The temperature rises. As a result, the temperature of the bulging part 85 provided in the partition wall 8 becomes high, the temperature sensing part 11a of the temperature sensor 11 is heated by the radiant heat from the bulging part 85, and a high temperature comes to be detected.

  FIG. 6 is an explanatory diagram showing a result of measuring a change in temperature detected by the temperature sensor 11 with varying degrees of fin clogging. As shown in the figure, the output (detected temperature) of the temperature sensor 11 gradually increases when combustion starts, and eventually stabilizes at a certain temperature. Further, the temperature when stabilized becomes higher as the degree of fin clogging increases. Therefore, information on the degree of fin clogging can be obtained by detecting the temperature after the time (stabilization time) after the start of combustion until the detected temperature stabilizes. In the composite heat source apparatus 10 of the present embodiment, the degree of fin clogging of the first heat exchanger 3-1 and the second heat exchanger 3-2 is detected using such a principle.

  As described above with reference to FIG. 3, the temperature sensor 11 is inserted between the two wall plates 81, and the two wall plates 81 are provided with a gap therebetween. Therefore, when the bulging portion 85 of one wall plate 81 is heated, the heat is not transmitted to the other wall plate 81 by heat conduction (so-called heat sink). Furthermore, since the partition plate 83 is provided in between, the other wall plate 81 is not heated by the radiation from the one wall plate 81. For this reason, the temperature sensor 11 is affected by the heated wall plate 81 even if fin clogging occurs in either the first heat exchanger 3-1 or the second heat exchanger 3-2. In addition, it can be detected in the same manner that the bulging portion 85 on the side where the fin clogging has occurred is heated. In addition, the sensor body 11 c of the temperature sensor 11 is positioned so as to be sandwiched from both sides by the sandwiching portion 86. For this reason, since the distance from the temperature sensing part 11a of the temperature sensor 11 to the bulging part 85 on either side is the same, either the first heat exchanger 3-1 or the second heat exchanger 3-2 is used. It is possible to detect clogging of fins with high accuracy.

  Generally, when fin clogging is detected, the rotational speed of the combustion fan 6 is increased. If the rotational speed of the combustion fan 6 is increased, the amount of air supplied increases, so that the reduction in the amount of air due to clogging of the fins can be compensated and the ratio of fuel gas to combustion air can be returned to an appropriate ratio. As a result, the combustion state can be returned to a good state, and the combustion gas temperature can be recovered to a normal temperature.

  However, when the combustion air is simultaneously supplied from one combustion fan 6 to the first burner 2-1 and the second burner 2-2 as in the composite heat source apparatus 10 of the present embodiment shown in FIG. The situation will be slightly different. That is, when the rotation speed of the combustion fan 6 is increased simply because fin clogging occurs in one heat exchanger while the first burner 2-1 and the second burner 2-2 are burning simultaneously. The amount of air supplied to the other burner also increases. As a result, in the other burner, the ratio of air to fuel gas (air-fuel ratio) is larger than the optimum value at the time of design (air is excessive), and it may be difficult to maintain a good combustion state. Can occur. Of course, if the rotational speed of the combustion fan 6 is not increased despite the occurrence of fin clogging, it may not be possible to maintain a good combustion state with the burner on which fin clogging has occurred.

  Therefore, in the composite heat source apparatus 10 of the present embodiment, the rotational speed of the combustion fan 6 is controlled even when the first burner 2-1 and the second burner 2-2 are burning simultaneously by performing the following control. By appropriately correcting, it is possible to maintain a good combustion state.

C. Overview of correction of combustion fan speed during simultaneous operation:
FIG. 7 shows an outline of the control performed by the composite heat source apparatus 10 of this embodiment for correcting the rotational speed of the combustion fan 6 even during simultaneous combustion of the first burner 2-1 and the second burner 2-2. It is the flowchart which showed. This process is a process executed by the controller 12 mounted on the composite heat source apparatus 10.

  When the process is started, it is determined whether or not the composite heat source apparatus 10 is in operation (that is, whether either the first burner 2-1 or the second burner 2-2 is in combustion) (step S10). As described above, the controller 12 detects the water flow to the first heat exchanger 3-1 and ignites the first burner 2-1, operates the circulation pump for the bathtub, or the second burner 2. Therefore, it is possible to immediately determine whether or not the composite heat source apparatus 10 is in operation. As a result, if the combined heat source apparatus 10 is not in operation (step S10: no), the process is terminated as it is, and then the process returns to the top again to repeat the determination in step S10. On the other hand, when the composite heat source apparatus 10 is in operation (step S10: yes), it is determined whether or not the bath side is in operation (that is, the second burner 2-2 is in combustion) ( Step S12).

  As a result, when the bath side is not in operation (step S12: no), the hot water supply side is operating alone (the first burner 2-1 is in combustion but the second burner 2-2 is in combustion). It is possible to judge that it is not in the middle). Therefore, in this case, processing for acquiring the rank on the hot water supply side is started (step S100). Here, the rank is an index indicating whether or not fin clogging has occurred and, if fin clogging has occurred, the degree thereof. In addition, as described above with reference to FIG. 1, the composite heat source unit 10 of the present embodiment is provided with the first heat exchanger 3-1 for hot water supply and the second heat exchanger 3-2 for bath. Since fin clogging can occur in each case, ranks, which are indices indicating the degree of fin clogging, are also acquired on the hot water supply side and the bath side. The process of acquiring the hot water supply side rank will be described in detail later.

  On the other hand, if the bath side is in operation (the second burner 2-2 is in combustion) (step S12: yes), is the hot water supply side in operation (the first burner 2-1 is in combustion)? It is determined whether or not (step S14). As a result, when the hot water supply side is not in operation (step S14: no), the bath side is operating alone (the first burner 2-1 is not in combustion, but the second burner 2-2 is It can be determined that the combustion is in progress. Therefore, in this case, processing for acquiring the bath side rank is started (step S200). The rank on the bath side can be acquired by almost the same processing as the rank on the hot water supply side. Therefore, the details of the process of acquiring the bath side rank will be described together with the process of acquiring the hot water supply side rank.

  On the other hand, when the hot water supply side is in operation (step S14: yes), the first burner 2-1 and the second burner 2-2 are burning simultaneously. Therefore, in order to appropriately correct the rotational speed of the combustion fan 6 according to the state of fin clogging in the first heat exchanger 3-1 and the state of fin clogging in the second heat exchanger 3-2. Then, the fan rotation speed correction process is started (step S300). Although details will be described later, the fan rotation speed correction process is based on the hot water supply side rank acquired in the hot water supply side rank acquisition process (step S100) and the bath side rank acquired in the bath side rank acquisition process (step S200). Thus, the rotational speed of the combustion fan 6 is corrected. As a result, even when the hot water supply side first burner 2-1 and the bath side second burner 2-2 are simultaneously burned while the degree of fin clogging is different between the hot water supply side and the bath side, This burner can also be kept in a good combustion state.

C-1. Obtaining hot water rank and bath rank:
FIG. 8 is a flowchart of hot water supply side rank acquisition processing performed to acquire the hot water supply side rank. As described above with reference to FIG. 7, this process is executed by the controller 12 when the hot water supply burner (first burner 2-1) is burning alone (when the hot water supply side is operating independently). Process. When the hot water supply side rank acquisition process is started, first, it is determined whether or not the stabilization time has elapsed since the start of the single operation on the hot water supply side (step S102). Here, the stabilization time is the time required until the temperature detected by the temperature sensor 11 is substantially stabilized, as described above with reference to FIG. The stabilization time is typically set to a time of about 120 seconds to 180 seconds. As a result, when the stabilization time has not yet elapsed since the start of the independent operation (step S102: no), the temperature detected by the temperature sensor 11 is changing and reflects the degree of fin clogging. Therefore, the hot water supply side rank acquisition process is terminated without acquiring a rank that is an index related to the degree of fin clogging.

  On the other hand, when the stabilization time has elapsed since the hot water supply side independent operation was started (step S102: yes), the current hot water supply side rank value (rank value L) is acquired (step S104). ). That is, the memory built in the controller 12 is provided with areas for storing the rank value L for each of the hot water supply side and the bath side, and each rank value L is set to “0” in the initial state. However, each time the hot water supply side or bath side rank is acquired, the corresponding rank value L is updated. In step S104, a process of reading the rank value L of the hot water supply side rank stored in the memory of the controller 12 is performed.

  Then, it is determined whether or not the read hot water supply side rank value L is “0” (step S106). If the rank value L is “0” (step S106: yes), the temperature detected by the temperature sensor 11 is detected. Is higher than the threshold temperature Th (0) (not included if equal) (step S108). Here, the threshold temperature Th (0) is a temperature serving as a threshold for determining whether the rank value L is “0” or “1”. That is, as described above with reference to FIG. 6, the temperature detected by the temperature sensor 11 after the stabilization time has elapsed is lowest when fin clogging has not occurred, and as the degree of fin clogging increases. Get higher. Therefore, if the degree of fin clogging is divided into six stages from a state in which no clogging occurs (rank value L = 0) to a state in which clogging is very advanced (rank value L = 5), By setting five threshold temperatures Th so that the temperature gradually increases from Th (0) to Th (4) and comparing the detected temperature of the temperature sensor 11 with these threshold temperatures Th, L can be determined. In the memory of the controller 12, five threshold temperatures Th (0) to Th (4) are stored for determining the rank value L on the hot water supply side. Here, since the current hot water supply side rank value L is “0” (step S106: yes), it is determined whether the rank value L is “0” or “1”. The threshold temperature Th (0) is read from the memory and compared with the temperature detected by the temperature sensor 11.

  As a result, if the temperature detected by the temperature sensor 11 is not higher than the threshold temperature Th (0) (step S108: no), fin clogging has not occurred and the current rank value L is changed from “0”. Since there is no need, the hot water supply side rank acquisition process is terminated as it is, and the process returns to the process of FIG. On the other hand, when the detected temperature of the temperature sensor 11 is higher than the threshold temperature Th (0) (step S108: yes), even if a predetermined holding time (for example, 30 seconds) elapses, After confirming that the detected temperature is not higher than the threshold temperature Th (0) (step S110: yes), the hot water supply side rank value L is increased by one (step S112). On the other hand, if the detected temperature of the temperature sensor 11 becomes lower than the threshold temperature Th (0) while the predetermined holding time has elapsed (step S110: no), the rank value L is not increased. Then, the hot water supply side rank acquisition process is terminated as it is, and the process returns to the process of FIG.

  As described above, the temperature sensing portion 11a of the temperature sensor 11 is only indirectly heated by the radiant heat from the bulging portion 85, and since the temperature sensing portion 11a and the sensor body 11c also have heat capacity, temperature The detection temperature of the sensor 11 does not change rapidly. In other words, when the holding time elapses, the detected temperature becomes lower than the threshold temperature Th (0). This means that the detected temperature has increased due to the influence of some noise, or the detected temperature is the threshold temperature Th. This is considered to be the case when it almost matches (0). Therefore, when the temperature detected by the temperature sensor 11 is higher than the threshold temperature Th (0) (step S108: yes), the state does not change even if a predetermined holding time (for example, 30 seconds) elapses. By checking, it is possible to increase the rank value L only when the fin clogging really occurs. In order to confirm that the state does not change even after the holding time has elapsed, the detected temperature and the threshold temperature may be compared once again after the holding time has elapsed. It is desirable to compare the detected temperature and the threshold temperature continuously or several times at regular intervals until the time elapses.

  The process when the current rank value L is determined to be “0” (step S106: yes) has been described above. On the other hand, if the current rank value L is not “0” (step S106: no), whether or not the detected temperature of the temperature sensor 11 is higher than the threshold temperature Th (L) (included if equal) Is not present) (step S114). For example, if the current rank value L is “1”, the threshold temperature Th (1) for determining whether or not to increase the rank value L to “2” is compared with the detected temperature of the temperature sensor 11. . If the current rank value L is “2”, it is compared with a threshold temperature Th (2) for determining whether or not to increase the rank value L to “3”. In this way, the threshold temperature Th (L) determined according to the current rank value L is compared with the detected temperature of the temperature sensor 11 to determine whether or not the detected temperature is higher than the threshold temperature Th (L). To do. As described above, the threshold temperatures Th (0) to Th (4) are stored in the memory of the controller 12.

  As a result, when the detected temperature of the temperature sensor 11 is higher than the threshold temperature Th (L) corresponding to the current rank value L (step S114: yes), a predetermined holding time (for example, 30 seconds) has elapsed. However, it is confirmed that the state does not change (step S116: yes), and the hot water supply side rank value L is increased by one (step S118). On the other hand, when the detected temperature of the temperature sensor 11 becomes lower than the threshold temperature Th (L) while the predetermined holding time elapses (step S116: no), the rank value L is not increased. Then, the hot water supply side rank acquisition process is terminated as it is, and the process returns to the process of FIG. When confirming that the state does not change even if the holding time elapses, the detected temperature and the threshold temperature are set continuously or several times until the holding time elapses. It is desirable to compare

  When the current rank value L is increased by 1 (step S118), it is determined whether or not the increased rank value L has reached “5” (step S120). If the rank value L has reached “5” (step S120: yes), it is considered that the fin clogging has progressed so much that the operation on the hot water supply side is urgently stopped for safety. On the other hand, when the rank value L has not reached “5” (step S120: no), the hot water supply side rank acquisition process is terminated as it is, and the process returns to the process of FIG.

  On the other hand, if the detected temperature of the temperature sensor 11 is not higher than the threshold temperature Th (L) corresponding to the current rank value L (step S114: no), this time, the threshold temperature Th (L) − It is determined whether it is lower than 30 (not included if equal) (step S122). As a result, when the detected temperature is lower than the threshold temperature Th (L) -30 (step S122: yes), it is confirmed that the state does not change even after a predetermined holding time has elapsed (step S124: yes), the current rank value L is decreased by one (step S126). In contrast, when the detected temperature of the temperature sensor 11 is not lower than the threshold temperature Th (L) -30 (step S122: no), or the detected temperature is lower than the threshold temperature Th (L) -30. However, if the state changes before the holding time elapses (step S124: no), the current rank value L is not decreased and the hot water supply side rank acquisition process is performed as it is. To return to the processing of FIG.

  Thus, in the hot water supply side rank acquisition process of the present embodiment, when the threshold temperature Th (L) corresponding to the current rank value L is acquired, whether or not the rank value L is increased for the threshold temperature Th (L). And a temperature lower by 30 degrees than the threshold temperature Th (L) is used as a threshold for determining whether or not to reduce the rank value L. Of course, the temperature used as the threshold value for determining whether or not to decrease the rank value L is stored as the threshold temperature Th (L) for each rank value L, and this threshold temperature Th (L) is read out. It may be determined whether or not the current rank value L is decreased.

  In the above, the hot water supply side rank acquisition process (step S100) performed when the 1st burner 2-1 for hot water supply is burning independently (step S12 of FIG. 7: yes) was demonstrated. On the other hand, when the second burner 2-2 for bath is burning alone (step S14 in FIG. 7: yes), a bath-side rank acquisition process (step S200) is performed. In this bath side rank acquisition process, the same process as the hot water supply side rank acquisition process described with reference to FIG. 8 is performed. However, the threshold temperatures Th (0) to Th (4) referred to in the bath side rank acquisition process are slightly higher than the threshold temperatures Th (0) to Th (4) referred to in the hot water supply side rank acquisition process. Is set

  As described above, in the composite heat source apparatus 10 of the present embodiment, the rank value L indicating the degree of fin clogging on the hot water supply side or the bath side is acquired in the single operation on the hot water supply side or the bath side, respectively. Then, during simultaneous operation on the hot water supply side and the bath side, the fan rotation speed correction process described below is performed based on the rank value L acquired in advance.

C-2. Fan rotational speed correction process of the first embodiment:
FIG. 9 is a flowchart showing the fan rotation speed correction process of the first embodiment. As described above with reference to FIG. 7, this process is a process executed by the controller 12 when the hot water supply side and the bath side are operated simultaneously.

  When the fan rotational speed correction process (step S300) of the first embodiment is started, first, the hot water supply side rank value and the bath side rank value stored in the memory of the controller 12 are acquired (step S302). Subsequently, it is determined whether or not the rank values on the hot water supply side and the bath side are both “0” (step S304). As described above, the rank value “0” is a rank value indicating that fin clogging has not occurred. Therefore, if any rank value is “0” (step S304: yes), it is not necessary to correct the rotational speed of the combustion fan 6. Therefore, the fan rotational speed correction process in FIG. Return to the indicated process.

  On the other hand, if the rank value on either the hot water supply side or the bath side is not “0” (step S304: no), the correction amount of the rotational speed of the combustion fan 6 is determined by referring to the correction table. Determine (step S306). FIG. 10 is an explanatory diagram showing a correction table stored in advance in the memory of the controller 12. As shown in the drawing, the correction amount of the rotational speed of the combustion fan 6 is set in the correction table in association with the combination of the hot water side rank value and the bath side rank value. For example, for the combination of the hot water supply side rank value “0” and the bath side rank value “2”, it is set that the rotation speed of the combustion fan 6 set as a standard is increased by 5%. Yes. Therefore, the correction amount of the rotational speed of the combustion fan 6 can be determined by referring to the correction table of FIG. 10 based on the hot water supply side rank value and the bath side rank value acquired in step S302. Here, the correction amounts for the hot water supply side rank value and the bath side rank value are set as follows.

  FIG. 11 is an explanatory diagram showing how correction amounts for hot water supply side rank values and bath side rank values are determined. In a state where fin clogging has not occurred on either the hot water supply side or the bath side (both rank values are “0”), as shown in FIG. 11A, a hot water supply burner (first burner 2-1) In addition, the rotational speed of the combustion fan 6 is set so that the excess air ratio of the bath burner (second burner 2-2) becomes a standard value. Here, the excess air ratio is an index indicating how much air is excessive with respect to the fuel gas. The excess air ratio “1” represents a state in which air that just burns the fuel gas is supplied (a state in which there is no excess air), and an excess air ratio smaller than “1” completely burns the fuel gas. This represents a state in which sufficient air is not supplied (a state in which air is insufficient), and an excess air ratio greater than “1” indicates a state in which more air than the fuel gas is completely combusted is supplied (air Represents an excessive state). When the excess air ratio decreases, the fuel gas becomes incompletely combusted, and conversely, when it increases, the fuel gas does not combust (fires out). For this reason, in order to stably burn the hot water supply burner (first burner 2-1) and the bath burner (second burner 2-2) in an appropriate state, the excess air ratio is in an appropriate range. (Between the allowable lower limit value and the allowable upper limit value). And in the state where fin clogging does not occur, both the excess air ratio on the hot water supply side and the excess air ratio on the bath side become standard values with a margin for both the lower limit value and the upper limit value. The rotational speed of the combustion fan 6 is set.

  As described above, when the excess air ratio becomes small, an incomplete combustion state occurs, and when the excess air ratio becomes smaller, the fuel gas cannot be combusted (fires out). Therefore, the excess air ratio has a lower limit value and an upper limit value at which the fuel gas can be combusted. However, the lower limit value and upper limit value of the excess air ratio shown in FIG. 11 are not such combustible limit values (misfire limit values), and the fuel gas can be stably combusted at an acceptable level. Limit value (a limit value with a margin for the misfire limit value).

  However, it is assumed that clogging occurs on either the hot water supply side or the bath side. Then, since the passage resistance in the heat exchanger increases on the side where the clogging occurs, the air supply amount decreases and the excess air ratio decreases. Further, on the side where clogging does not occur, the air supply amount increases and the excess air ratio increases due to the influence of the passage resistance increasing on the other side. In FIG. 11 (b), mild (rank value 1) fin clogging occurs on the hot water supply side, and as a result, the excess air ratio on the hot water supply side decreases and the excess air ratio on the bath side increases. The situation is shown. Note that the excess air ratio on the hot water supply side is indicated by a black circle, and the excess air ratio on the bath side is indicated by a white circle, because the hot water side is more clogged with fins than the bath side. This means that

  As shown in FIG. 11 (b), on the other hand, when the fin clogging of rank value 1 occurs, the excess air ratio on both the hot water supply side and the bath side is within the allowable range (from the lower limit value to the upper limit value). Between). Therefore, it is not necessary to correct the rotational speed of the combustion fan 6 in this state. In addition, although the excess air ratio on the hot water supply side is lower than the standard value, the excess air ratio on the bath side is higher than the standard value, so combustion tends to bring the excess air ratio on the hot water supply side closer to the standard value. When the rotational speed of the fan 6 is increased, the excess air ratio on the bath side is moved away from the standard value. For this reason, even if the rotational speed of the combustion fan 6 is corrected, there is not much room for improvement by the correction.

  However, when the fin clogging on one side (here, the hot water supply side) proceeds to the rank value 2, as shown by the solid line in FIG. Will also decline. Therefore, the rotational speed of the combustion fan 6 is increased so that the excess air ratio on the hot water supply side becomes larger than the lower limit value. Moreover, since the amount of air supplied to the bath side increases with this, the excess air ratio on the bath side also increases. However, since the rotation speed is increased only to the extent that the excess air ratio on the hot water supply side exceeds the lower limit value, the excess air ratio on the bath side does not exceed the upper limit value. In FIG. 11C, the excess air ratio on the hot water supply side and the bath side in a state where the rotation speed of the combustion fan 6 is increased is indicated by a broken line.

  When the hot water supply side fin clogging has progressed to the rank value 3, the amount of increase in the rotational speed of the combustion fan 6 can be determined in substantially the same manner. That is, the rotational speed of the combustion fan 6 is increased to such an extent that the excess air ratio on the fin clogging side (here, the hot water supply side) exceeds an allowable lower limit value. At this time, it is confirmed that the excess air ratio on the bath side does not exceed an allowable upper limit value.

  Of course, when the rotational speed of the combustion fan 6 is increased so that the excess air ratio on the side where the fin clogging occurs is larger than the lower limit value, the other excess air ratio exceeds the allowable upper limit value. Cases can also occur. For example, as shown in FIG. 11 (d), when the clogging of fins has progressed to a considerable degree (up to a rank value of 4) on the hot water supply side even though the bath side is not clogged with fins, On the hot water supply side, the amount of air supplied decreases and the excess air ratio decreases considerably. On the other hand, on the bath side, the amount of supplied air increases and the excess air ratio rises to some extent. For this reason, if the rotational speed of the combustion fan 6 is increased until the excess air ratio on the hot water supply side exceeds the allowable lower limit value, the excess air ratio on the bath side exceeds the allowable upper limit value. In this case, in order to return the combustion on the side where the fin clogging has occurred (here, the hot water supply side) to the normal state, the combustion state on the side where the combustion is normal (here, the bath side) is changed to an abnormal state. It will be a fall over at the end because it will be. Therefore, in such a case, as indicated by a broken line in FIG. 11D, the rotational speed of the combustion fan 6 is increased until the excess air ratio on the bath side where fin clogging does not occur reaches the upper limit value. increase. As a result, the excess air ratio on the hot water supply side is slightly lower than the lower limit value. However, the combustion state can be greatly improved as compared with before the rotation speed of the combustion fan 6 is increased.

  The case where fin clogging has occurred only on the hot water supply side and fin clogging has not occurred on the bath side has been described above. Of course, even if fin clogging does not occur on the hot water supply side and fin clogging occurs only on the bath side, the amount of increase in the rotational speed of the combustion fan 6 can be determined in exactly the same manner. Further, when fin clogging occurs on either the hot water supply side or the bath side, the amount of increase in the rotational speed of the combustion fan 6 is determined as follows.

  FIG. 12 is an explanatory diagram showing a state in which the amount of increase in the rotational speed of the combustion fan 6 is determined when fin clogging occurs on either the hot water supply side or the bath side. First, when the hot water supply side and the bath side are clogged to the same extent (that is, when the hot water supply side rank value and the bath side rank value are equal), the excess air ratio is reduced in the same way. it is conceivable that. Therefore, in this case, the rotational speed of the combustion fan 6 may be increased so that the excess air ratio on both the hot water supply side and the bath side becomes the standard value. FIG. 12A shows how the rotational speed of the combustion fan 6 is increased when both the hot water supply side and bath side rank values are “2”. Incidentally, as in the case where both rank values are “1”, the excess air ratio on both the hot water supply side and the bath side is within the allowable range (between the lower limit value and the upper limit value). In such a case, the rotational speed of the combustion fan 6 need not be increased.

  Next, when the degree of fin clogging differs greatly between the hot water supply side and the bath side (for example, when the difference in rank value is “2” or more), the amount of increase in the rotational speed of the combustion fan 6 is determined as follows. To do. For example, as shown in FIG. 12B, when the rank value on the hot water supply side is “3” and the rank value on the bath side is “1”, the excess air ratio with the larger rank value is greatly reduced. The lower the excess air ratio, the smaller the rank value is. Therefore, in this case, the rotational speed of the combustion fan 6 is increased so that the excess air ratio of the larger rank value (here, the hot water supply side) exceeds the lower limit value. At this time, care should be taken so that the excess air ratio of the smaller rank value (here, the bath side) does not exceed the upper limit value. As a result, if the excess air ratio with the smaller rank value exceeds the upper limit value, the increase in the rotational speed of the combustion fan 6 is stopped to the extent that the upper limit value is not exceeded. Accordingly, when the difference in rank value is “3” or more, the increase in the rotational speed of the combustion fan 6 is limited, so that a warning lamp or the like is notified, and the larger rank value can be used only by itself. It is desirable to make it.

  Also, if the level of fin clogging differs on the hot water supply side and the bath side, but the difference in the level is not so great (for example, the difference between the rank values is “1”), the air with the higher rank value is used. When the rotational speed of the combustion fan 6 is increased until the excess ratio exceeds the lower limit value, the air excess ratio with the smaller rank value may not return to the standard value. In such a case, it is possible to increase the rotational speed a little more. For example, as shown in FIG. 12C, when the rank value on the hot water supply side is “2” and the rank value on the bath side is “1”, the excess air ratio of the larger rank value (hot water supply side) is By simply increasing the rotational speed of the combustion fan 6 to the extent that the lower limit value is reached, the excess air ratio of the smaller rank value (bath side) can only return to near the standard value. Therefore, as indicated by the broken line in FIG. 12C, the amount of increase in the rotational speed of the combustion fan 6 may be determined until both excess air ratios are close to the standard value.

  In the correction table shown in FIG. 10, the amount of increase in the rotational speed of the combustion fan 6 determined in accordance with the rank values on the hot water supply side and the bath side as described above is set. In step S306 of the fan rotation speed correction process in FIG. 9, the rotation of the combustion fan 6 is performed by referring to the correction table in FIG. 10 based on the hot water supply side rank value and the bath side rank value acquired in advance. Determine the speed correction amount. Then, after correcting the rotational speed of the combustion fan 6 according to the correction amount thus determined (step S308), the fan rotational speed correction process of FIG. 9 is terminated, and the process returns to the process of FIG.

  In the fan rotation speed correction process of the first embodiment described above, the hot water supply side rank value, which is an index related to hot water supply side clogging, and the bath side rank value, which is an index related to bath side fin clogging, are combined. Based on this, it is possible to correct the rotational speed of the combustion fan 6 so that the excess air ratio on both the hot water supply side and the bath side falls within the allowable range as much as possible. For this reason, even when the degree of fin clogging differs between the hot water supply side and the bath side, the rotational speed of the combustion fan 6 can be corrected so that an appropriate combustion state is maintained on either side. .

  The hot water supply side rank value and the bath side rank value are acquired in advance when the hot water supply side or the bath side is independently operated, respectively, and are acquired in advance when simultaneous operation of the hot water supply side and the bath side is started. The correction amount of the rotational speed of the combustion fan 6 can be determined simply by referring to the correction table from the hot water supply side rank value and the bath side rank value. For this reason, when simultaneous operation is started, the combustion fan 6 can be immediately rotated at an appropriately corrected rotation speed.

C-3. Fan rotation speed correction process of the second embodiment:
In the fan rotational speed correction process of the first embodiment described above, the correction amount corresponding to the combination of the hot water supply side rank value and the bath side rank has been described as being set in advance in the correction table in the memory of the controller 12. However, it is also possible to correct the rotation speed according to the rank values on the hot water supply side and the bath side without using the correction table. Hereinafter, the fan rotation speed correction process of the second embodiment will be described.

  FIG. 13 is a flowchart showing fan rotation speed correction processing according to the second embodiment. This process is a process executed in place of the fan rotation speed correction process (step S100) of the first embodiment described above in the process shown in FIG. As shown in FIG. 13, when the fan rotation speed correction process (step S350) of the second embodiment is started, first, the hot water supply side rank value and the bath side rank value are acquired (step S352). These rank values are stored in the memory of the controller 12. Subsequently, it is determined whether or not the rank values on the hot water supply side and the bath side are both “0” (step S354). As a result, if any rank value is “0” (step S354: yes), it is not necessary to correct the rotational speed of the combustion fan 6, so the fan rotational speed correction process in FIG. The processing returns to the processing shown in FIG.

  On the other hand, when the rank value on either the hot water supply side or the bath side is not “0” (step S354: no), the correction amount of the rotational speed of the combustion fan 6 is determined as follows. First, a larger rank value is selected from the hot water supply side rank value and the bath side rank value, and a correction amount candidate value is acquired based on the rank value (step S356). Here, the correction amount candidate value corresponds to a case where the correction amount may be corrected later. Further, the correction amount candidate values are stored in advance in the memory of the controller 12 for each of the rank values “1” to “4”. If the rank values on the hot water supply side and the bath side are the same, a correction amount candidate value is acquired based on one of the rank values except when the rank value is “0”. Corresponding to this, no candidate value for the correction amount is set for the rank value “0”.

  FIG. 14 is an explanatory diagram showing a state in which a candidate value for the correction amount for the rotational speed of the combustion fan 6 is set in association with the larger rank value. FIG. 14A illustrates a candidate value table in which candidate values for correction amounts are set in association with respective rank values. Further, FIG. 14B illustrates on what basis the values of these candidate value tables are set. For example, when the larger rank value is “1”, the smaller rank value can take only “0” or “1”. In any case, it is not necessary to greatly increase the rotational speed of the combustion fan 6. Therefore, a relatively small correction amount may be set as a correction amount candidate value for the rank value “1”. Here, assuming that both rank values are “1”, the candidate value of the correction amount for the rank value “1” is set to increase the rotational speed by 2%.

  For example, when the larger rank value is “3”, the smaller rank value can take any value from “0” to “3”. If the lower rank value is “0” (that is, a combination of the rank value “3” and the rank value “0”), as shown in FIG. It is considered that the excess air ratio is greatly reduced in the burner on the 3 ”side, and conversely, the excess air ratio is higher than the standard value in the burner on the rank side of“ 0 ”. Of course, since the smaller rank value can take values of “1” to “3”, the excess air ratio on the smaller rank value side also changes according to the value. Therefore, for the time being, the one with the smaller rank value is scrutinized, focusing only on the one with the larger rank value, and the rotational speed of the combustion fan 6 so that the excess air ratio with the larger rank value exceeds the lower limit value. Is set in the candidate value table. If the rotational speed of the combustion fan 6 is corrected so that the excess air ratio at the higher rank value exceeds the lower limit value, the excess air ratio at the smaller rank value may exceed the upper limit value. However, in the candidate value table, candidate values for the correction amount are set without considering this point.

  In step S356 of the fan rotation speed correction process shown in FIG. 13, the candidate value of the correction amount for the larger rank value is acquired by referring to the candidate value table set as described above. Subsequently, an allowable value for the rotational speed correction amount is acquired based on the smaller rank value (step S358). The allowable value of the correction amount is also stored in advance in the memory of the controller 12 for each rank value of “0” to “4”. The allowable value of the correction amount is stored even when the smaller rank value is “4” in consideration of the case where both the hot water supply side and bath side rank values are “4”. Because it is.

  FIG. 15 is an explanatory diagram showing a state in which an allowable value of the correction amount for the rotational speed of the combustion fan 6 is set in association with the smaller rank value. FIG. 15A illustrates an allowable value table in which an allowable value of the correction amount is set in association with each rank value. Further, FIG. 15B illustrates on what basis the values in the allowable value table are set. For example, when the smaller rank value is “0”, the larger rank value can take values “1” to “4”. If the larger rank value is “1” (ie, the smaller rank value is “0” and the larger rank value is “1”), the rank value is “0”. The excess air ratio of the burner on the side is higher than the standard value due to a slight decrease in the excess air ratio of the burner on the other side, but is only slightly higher. Therefore, even if the rotational speed of the combustion fan 6 is increased considerably, it is considered that the excess air ratio on the side of the rank value “0” does not reach the upper limit value. On the other hand, if the larger rank value is “4” (ie, the smaller rank value is “0” and the larger rank value is “4”), the rank value is However, the excess air ratio on the “4” side is significantly reduced, and the excess air ratio is considerably higher than the standard value even on the rank value “0” side. Therefore, in this case, if the rotational speed of the combustion fan 6 is increased too much, it is considered that the excess air ratio on the side of the rank value “0” exceeds the upper limit value.

  Therefore, even if the smaller rank value is “0”, the larger rank value is “0” and “4”, and the rank value is “4”. However, the allowable increase in the rotational speed is small. In general, the larger the higher rank value, the smaller the allowable increase in rotational speed. Therefore, when the smaller rank value is “0”, the larger rank value is assumed to be “4”, and at that time, the smaller rank value (here, the rank value is “0”). The increase amount of the rotational speed at which the excess air ratio at the side) reaches the upper limit value is set as an allowable value of the correction amount for the smaller rank value “0”.

  In the above, the method of setting the correction amount tolerance when the smaller rank value is “0” has been described. However, when the smaller rank value takes a value of “1” to “4”, In almost the same way, the allowable value of the correction amount for each rank value can be set. That is, assuming that the larger rank value is “4”, the amount of increase in rotational speed at which the excess air ratio on the smaller rank value side reaches the upper limit value is set to the smaller rank value “0”. Is set as an allowable value for the correction amount. Note that an increase in the smaller rank value means that the excess air ratio decreases on both the larger and smaller rank values. Accordingly, as shown in FIG. 15A, the tolerance value of the correction amount set in the tolerance value table is set to a larger value as the smaller rank value increases.

  In step S358 of the fan rotation speed correction process shown in FIG. 13, the allowable value of the correction amount for the smaller rank value is acquired by referring to the allowable value table set as described above. Then, the previously obtained correction amount candidate value is compared with the allowable correction amount value to determine whether the candidate value is equal to or smaller than the allowable value (step S360). That is, it is determined whether or not the correction amount candidate value determined based on the larger rank value is an allowable correction amount in light of the smaller rank value. As a result, if the candidate value is equal to or smaller than the allowable value (step S360: yes), the candidate value is determined as the final correction amount (step S362). On the other hand, when the candidate value exceeds the allowable value (step S360: no), the allowable value is determined as the final correction amount (step S364). Then, after correcting the rotational speed of the combustion fan 6 according to the correction amount thus determined (step S366), the fan rotational speed correction process of the second embodiment shown in FIG. 13 is terminated and the process returns to the process of FIG. To do.

  Also in the fan rotation speed correction process of the second embodiment described above, a combination of a hot water supply side rank value that is an index related to hot water clogging of the fins on the hot water supply side and a bath side rank value that is an index related to clogging of the fins on the hot water side Based on the above, the rotational speed of the combustion fan 6 can be corrected so that the excess air ratio on both the hot water supply side and the bath side falls within an allowable range. For this reason, even when the degree of fin clogging differs between the hot water supply side and the bath side, the rotational speed of the combustion fan 6 can be corrected so that an appropriate combustion state is maintained on either side. .

  Further, in the fan rotation speed correction process of the second embodiment, the correction amount candidate value corresponding to the larger rank value (see FIG. 14) and the correction amount allowable value corresponding to the smaller rank value (FIG. 15). Need only be stored, and it is not necessary to store a matrix-like correction table as shown in FIG. For this reason, the memory capacity of the controller 12 can be saved.

  Nevertheless, as described above, it is only necessary to read out the correction amount candidate value corresponding to the larger rank value and the correction amount allowable value corresponding to the smaller rank value and compare them. The correction amount can be determined quickly. For this reason, when simultaneous operation on the hot water supply side and the bath side is started, it is possible to quickly determine the correction amount of the rotation speed and rotate the combustion fan 6 at the rotation speed appropriately corrected.

D. Modified example:
In the first embodiment and the second embodiment described above, it is necessary to know the rank value that is an index related to fin clogging for each of the hot water supply side and the bath side. In the above description, the rank value is acquired based on the detected temperature output from the temperature sensor 11 in a state where the single operation on the hot water supply side or the bath side is continued for a predetermined stabilization time (FIG. 9). reference). However, as long as an index relating to hot water supply side and bath side fin clogging can be obtained, the rank value can be obtained not only by the method shown in FIG. 9 but also by a different method. Below, the modification for acquiring these rank values is demonstrated.

D-1. First modification:
FIG. 16 is an explanatory diagram showing the principle of detecting the rank value based on the temperature change detected by the temperature sensor 11 when the simultaneous operation state is switched to the single operation state. For example, assuming that the detected temperature of the temperature sensor 11 when the hot water supply side and the bath side are simultaneously operated is Th, when switching from this state to the single operation, the detected temperature of the temperature sensor 11 decreases. At this time, the speed at which the detected temperature decreases varies depending on the temperature stabilized by the single operation.

  FIG. 16A shows a case where the temperatures stabilized by the single operation are the above-described threshold temperatures Th (0), Th (1), Th (2), Th (3), and Th (4), respectively. Is shown that the temperature detected by the temperature sensor 11 decreases after switching from simultaneous operation to single operation. As shown in the figure, the lower the temperature when stabilized, the faster the detected temperature decreases. Furthermore, in the period before the detected temperature is stabilized, the detected temperature that decreases with time can be approximated by a relatively simple expression (for example, a straight line). Therefore, within this period (approxible period), the detected temperature detected by the temperature sensor 11 is compared with the approximate expression, so that the detected temperature when stabilized is the threshold temperature Th (0) to Th (4). It can be predicted whether it is higher or lower than that, and as a result, the rank value can be obtained.

  Various methods can be used for setting the approximation possible period and for formulating the approximation formula within the approximation possible period. For example, as illustrated in FIG. 16B, the simultaneous operation is switched to the single operation. It is possible to approximate the decrease in the detected temperature of the temperature sensor 11 with a straight line within this period. The slope of the straight line at this time can be approximated by the slope when the temperature difference between the detected temperature Th at the time of switching and the temperature after stabilization is reduced by 80% of the stabilization time. For example, if the detected temperature after stabilization is the threshold temperature Th (3), as shown in FIG. 16B, within the approximate possible period, (Th (3) −Th) / (0. It can be expected that the detected temperature of the temperature sensor 11 decreases with a slope of (8 × stabilization time). Therefore, if the temperature actually detected by the temperature sensor 11 is lower than the expected temperature, the temperature at the time of stabilization should be lower than the threshold temperature Th (3). In the first modification, it is possible to acquire the rank value even at the stage before the stabilization time elapses after switching from the simultaneous operation to the single operation by using such a principle.

  FIG. 17 is a flowchart showing hot water supply side rank acquisition processing in the first modification. This process is a process executed in place of the above-described hot water supply side rank acquisition process (step S100) in the process shown in FIG. As shown in the figure, when the hot water supply side rank acquisition process (step S150) of the first modified example is started, whether the hot water supply side and the bath side are simultaneously switched to the hot water supply side independent operation, or the hot water supply side and the bath It is determined whether the hot water supply side individual operation is started from the state where none of the sides is operated (step S152). As a result, if the hot water supply side independent operation is started from the state where none is operated (step S152: no), the process of acquiring the rank value is not performed, and the hot water supply side rank acquisition of the first modified example is performed. The process ends.

  On the other hand, when switching from the hot water supply side and bath side simultaneous operation to the hot water supply side single operation (step S152: yes), after turning on the timer built in the controller 12 (step S154), The detected temperature Th of the temperature sensor 11 at the time of switching from the simultaneous operation to the single operation and the current rank value L (here, the hot water supply side rank value) are acquired (step S156). Then, based on the acquired detected temperature Th and rank value L, an approximate expression of threshold temperature (approximate expression for rank up) for determining whether or not to increase the current rank value, and the current rank value An approximate expression of threshold temperature (approximate expression for rank down) for determining whether or not to decrease is generated (step S158).

  FIG. 18 shows an approximate expression for the threshold temperature for rank up and an approximate expression for the threshold temperature for rank down. In other words, since the current rank value is “L”, the detected temperature of the temperature sensor 11 is determined by the slope of (Th (L) −Th) / (0.8 × stabilization time) from the temperature Th at the time of switching. If it decreases slowly, the temperature after the stabilization time has elapsed is considered to be higher than the threshold temperature Th (L). In this case, the current rank value may be increased. Therefore, this approximate expression can be used as an approximate expression of the threshold temperature for rank up. Further, if the temperature detected by the temperature sensor 11 decreases from the switching temperature Th faster than the slope of (Th (L) -30-Th) / (0.8 × stabilization time), stabilization is achieved. The temperature after the lapse of time is considered to be lower than the threshold temperature Th (L) -30. In this case, the current rank value may be decreased. Therefore, this approximate expression can be used as an approximate expression of the threshold temperature for rank down. In step S158 of FIG. 17, such an approximate expression for the threshold temperature for rank up and an approximate expression for the threshold temperature for rank down are generated.

  Subsequently, the temperature detected by the temperature sensor 11 is compared with the threshold temperature for rank up and / or the threshold temperature for rank down (step S160). That is, when the detected temperature of the temperature sensor 11 is higher than the threshold temperature for rank up or lower than the threshold temperature for rank down, comparison with the other threshold temperature is not performed. On the other hand, when the detected temperature of the temperature sensor 11 is lower than the rank-up threshold temperature, or higher than the rank-down threshold temperature, it is also compared with the other threshold temperature. Then, it is determined based on the count value of the timer whether or not the approximation possible period has ended (step S162). If the approximation possible period has not ended (step S162: no), the process returns to step S160 and returns to the temperature. The sensor 11 is compared with the threshold temperature for rank up and / or rank down. This comparison only needs to be performed at least once within the approximate period, but it is preferable to perform the comparison at predetermined time intervals so that a plurality of comparisons can be performed if possible.

  After the comparison between the detected temperature of the temperature sensor 11 and the threshold temperature is thus performed (step S160), when the approximation possible period ends (step S162: yes), whether the detected temperature is higher than the threshold temperature for rank increase. Is determined (step S164). When the comparison between the detected temperature and the threshold temperature is performed only once during the approximation possible period, the determination is made based on the comparison result. In addition, when a plurality of comparisons are performed during the approximation possible period, the determination is made based on the comparison result having the larger number among the comparison results. In this case, it is desirable to perform an odd number of comparisons during the approximate period. Alternatively, it may be determined that the detected temperature is higher than the threshold temperature (step S164: yes) only when the detected temperature is higher than the threshold temperature for rank up in all the comparison results of a plurality of times. Since the rank-up threshold temperature is given by an approximate expression, there is a possibility of erroneous determination if the detected temperature of the temperature sensor 11 is close to the threshold temperature. Therefore, a comparison is made a plurality of times, and all the results are judged that the detected temperature is higher than the threshold temperature (step S164: yes) only when the detected temperature is higher than the threshold temperature for rank increase. If it is made, it becomes possible to avoid misjudgment.

  Here, after switching from simultaneous operation to single operation, the state is described as being maintained until the approximate possible period ends. However, if the operation is returned to the simultaneous operation before the approximation possible period ends, or if the operation ends, the following may be performed. In the simplest case, it is sufficient that the process is immediately terminated on the assumption that the single operation period has not been sufficiently taken. In this case, the current rank value is maintained as it is. However, there are cases where the rank value can be sufficiently evaluated even when the approximate possible period has not ended, for example, when the approximate possible period is slightly less. Therefore, as long as the isolated operation time continues for a predetermined time or more, even if the approximate available period has not ended, it may be considered that the operation has been completed and the subsequent processing may be continued.

  If “yes” is determined in step S164, the current rank value L is increased by “1” (step S166). Thereafter, as a result of the increase, it is determined whether or not the rank value L has reached “5” (step S168). If the rank value L has reached “5” (step S168: yes), combustion is in progress. The first burner (here, the first burner 2-1 which is a hot water supply side burner) is stopped immediately. On the other hand, when the rank value L has not reached “5” (step S168: no), the hot water supply side rank acquisition process (step S150) of the first modification shown in FIG. 17 is terminated.

  On the other hand, if it is determined that the detected temperature of the temperature sensor 11 is not higher than the threshold temperature for rank up (step S164: no), this time, the detected temperature is lower than the threshold temperature for rank down. It is determined whether or not (step S170). This determination can also be made in the same manner as the determination in step S164. That is, if the detected temperature and the threshold temperature are compared only once during the approximate period, the determination is made based on the comparison result. In addition, when a plurality of comparisons are performed during the approximation possible period, the determination is made based on the comparison result having the larger number among the comparison results. Alternatively, it can be determined that the detected temperature is lower than the threshold temperature only when the detected temperature is lower than the threshold temperature for rank down (step S170: yes). By doing so, it is possible to avoid erroneous determination due to an error included in the approximate expression of the threshold temperature for rank down.

  As a result, when it is determined that the detected temperature of the temperature sensor 11 is lower than the threshold temperature for rank down (step S170: yes), after subtracting “1” from the current rank value L (step S172), FIG. The hot water supply side rank acquisition process of the first modification shown in FIG. On the other hand, if it is determined that the detected temperature is not lower than the threshold temperature for rank down (step S170: no), the current rank value L is not changed and the hot water supply side of the first modification is used as it is. The rank acquisition process ends.

  Although the process for acquiring the hot water supply side rank has been described above, the process for acquiring the bath side rank can be performed in exactly the same manner. However, the values of the threshold temperatures Th (0) to Th (4) may be set to values different from the case of obtaining the hot water supply side rank. In addition, the approximate expression for the threshold temperature for rank up or rank down may be different depending on whether the hot water supply rank is acquired or the bath rank is acquired. Furthermore, it is possible to use different approximation formulas for the approximation possible period depending on whether the hot water supply side rank is acquired or the bath side rank is acquired. For example, when obtaining the above-mentioned hot water supply side rank, it has been described that the approximation possible period starts immediately after switching from simultaneous operation to single operation. However, the approximable period may be started after a predetermined time has elapsed, not immediately after switching to the isolated operation.

  According to the hot water supply side rank acquisition process (and the bath side rank acquisition process) of the first modification described above, after the simultaneous operation on the hot water supply side and the bath side is switched to the single operation, before the stabilization time elapses ( That is, the current rank value can be updated even when the temperature detected by the temperature sensor 11 is changing. Since the stabilization time is a time required for the detection temperature of the temperature sensor 11 to stabilize, the stabilization time is actually set to a relatively long time such as 120 seconds or 180 seconds. Therefore, depending on the usage state of the composite heat source apparatus 10, it may not always occur that the isolated operation state continues for a time longer than the stabilization time. Even in such a case, according to the hot water supply side rank acquisition process (and the bath side rank acquisition process) of the first modification described above, the rank value can be updated with sufficient frequency. The state of fin clogging can always be properly grasped. As a result, the hot water supply side and bath side burners can always be maintained in an appropriate combustion state regardless of the degree of fin clogging. It becomes.

D-2. Second modification:
In the first modification described above, the rank value is acquired based on the speed at which the temperature detected by the temperature sensor 11 decreases when the hot water supply side and bath side simultaneous operation is switched to the single operation. However, the rank value may be acquired based on the speed at which the temperature detected by the temperature sensor 11 increases. Below, such a 2nd modification is demonstrated.

  FIG. 19 is an explanatory diagram showing the principle of obtaining the rank value in the second modification. The figure shows a state in which the temperature detected by the temperature sensor 11 rises when a single operation on the hot water supply side or bath side is started from the state where the composite heat source apparatus 10 is not operated. As described above, the temperature at which the temperature detected by the temperature sensor 11 stabilizes increases as fin clogging progresses. Corresponding to this, the speed (inclination) at which the detected temperature rises becomes faster (inclination becomes steep) as the fin clogging progresses. Therefore, if attention is paid to this, the rank value can be acquired as follows.

  First, the reference temperature Thc is set in advance. Then, after the hot water supply side or bath side independent operation is started, the timer is turned on when the temperature detected by the temperature sensor 11 exceeds the reference temperature Thc. Thereafter, when the predetermined time dt has elapsed, the temperature detected by the temperature sensor 11 (temperature rise from the reference temperature Thc) is acquired, and whether or not the current rank value is updated based on the temperature rise (increase) Whether to decrease, decrease, or maintain).

  In particular, as described above with reference to FIGS. 3 and 4, the temperature sensor 11 is not in contact with the bulging portion 85 of the wall plate 81 and is indirectly heated by the radiant heat from the bulging portion 85. The detected temperature of the temperature sensor 11 changes slowly without being affected by disturbances. Therefore, an accurate rank value can be acquired also by the method of detecting the temperature rise amount within the predetermined time dt as described above.

  Of course, the temperature rise amount within the predetermined time dt is detected not after the detected temperature of the temperature sensor 11 exceeds the reference temperature Thc but after a predetermined time has elapsed since the start of the independent operation. Also good. However, if the temperature rise from the time when the detected temperature of the temperature sensor 11 exceeds the reference temperature Thc is detected, the temperature at the start of measurement is fixed, so that the detected temperature after the predetermined time dt has elapsed. It corresponds to the amount of temperature rise as it is. For this reason, the process of subtracting the temperature at the start of measurement from the detected temperature after elapse of the predetermined time dt becomes unnecessary, and the control of the controller 12 can be simplified.

  Further, if the temperature rise from the time when the detected temperature of the temperature sensor 11 exceeds the reference temperature Thc is detected, the state when the single operation is started (that is, the combined heat source apparatus 10 is completely at room temperature). This is preferable because it is possible to always obtain the rank value under the same conditions regardless of whether the single operation is started from the state returned to (1) or the single operation is started completely before returning to room temperature). .

D-3. Third modification:
In the various examples and modifications described above, as shown in FIG. 1, two combustion units (a first burner 2-1 and a first heat exchanger 3-1 are disposed in a single can body 1. And the second burner 2-2 and the second heat exchanger 3-2) are mounted, and the combustion air is supplied from one combustion fan 6 to these two combustion units. did. However, the present invention can be suitably applied to any composite heat source machine as long as the combustion air is supplied from one combustion fan 6 to a plurality of combustion units. For example, as illustrated in FIG. 20, the first combustion unit (the first burner 2-1 and the first heat exchanger 3-1) is mounted in the first can body 1-1, and the second can A second combustion unit (second burner 2-2 and second heat exchanger 3-2) is mounted in the can body 1-2, and combustion air is supplied from one combustion fan 6 to these. The present invention can also be suitably applied to the composite heat source apparatus 10 to be supplied.

  As mentioned above, although the composite heat source machine 10 of various Example and modification was demonstrated, this invention is not restricted to said Example or modification, It can implement in a various aspect in the range which does not deviate from the summary. Is possible.

  For example, in the various embodiments and modifications described above, the first heat exchanger 3-1 is used for hot water supply, and the second heat exchanger 3-2 is used for bathing. However, the present invention is not limited to such a configuration. For example, the composite heat source apparatus 10 that uses the second heat exchanger 3-2 for heating or the first heat exchanger 3-1 is used for hot water supply and hot water supply for a bath. The present invention can also be suitably applied to the composite heat source apparatus 10 that is also used for the above.

DESCRIPTION OF SYMBOLS 1 ... Can body, 1-1 ... 1st can body, 1-2 ... 2nd can body,
2a ... Unit burner, 2b ... Mixing pipe part, 2c ... Gas manifold,
2d ... gas nozzle, 2-1 ... first burner, 2-2 ... second burner,
3a ... endothermic fin, 3b ... endothermic tube, 3c ... sealing plate,
3-1 ... 1st heat exchanger, 3-2 ... 2nd heat exchanger, 4 ... Distribution board,
4a ... distribution hole, 4b ... communication hole, 5 ... air supply chamber,
5a ... rising portion, 6 ... combustion fan, 7-1 ... first combustion chamber,
7-2 ... second combustion chamber, 8 ... partition wall, 9 ... exhaust hood,
9a ... exhaust port, 10 ... composite heat source machine, 11 ... temperature sensor,
11a ... temperature sensing part, 11b ... fixing part, 11c ... sensor body,
11d ... Lead wire, 12 ... Controller, 81 ... Wall plate,
81a ... shoulder, 81b ... hanging plate part, 81c ... bent part,
82: Air blowing hole, 83: Partition plate, 84: Ventilation hole,
85 ... bulge part, 86 ... clamping part, Th ... detected temperature,
Th (0) to Th (4) ... threshold temperature, dt ... predetermined time, Thc ... reference temperature

Claims (4)

A plurality of combustion units provided with a burner and a heat exchanger are provided, the combustion fan is rotated, and the combustion air is simultaneously supplied to the plurality of combustion units sharing the combustion fan. In a composite heat source machine that performs a combustion operation of a combustion unit supplied with fuel by supplying fuel to at least one burner,
Index acquisition for acquiring an index related to clogging of the fins of the heat exchanger for a combustion unit that is operating independently during single operation where a single combustion unit is performing combustion operation among the plurality of combustion units Means,
When obtaining an index related to the fin clogging, an index storage means for storing the index for each combustion unit;
Rotational speed correction means for correcting the rotational speed of the combustion fan based on the index for the combustion units that are operating simultaneously when two or more of the combustion units are operating simultaneously. It equipped with a door,
The rotational speed correction means is within an allowable amount determined according to an index of the one where the fin clogging is not progressing among the plurality of indices stored for the combustion units that are operating simultaneously. A correction amount determining means for determining a correction amount of the rotation speed based on an index of the one where the fin clogging is progressing;
The composite heat source machine , wherein the rotational speed of the combustion fan is corrected according to the correction amount determined by the correction amount determination means . The composite heat source machine according to claim 1,
The plurality of combustion units are mounted in each compartment in which a single can is partitioned into a plurality of partitions by a partition wall,
The partition wall has a hollow structure in which two plate members are arranged with a gap therebetween, and air from the combustion fan is supplied to the gap, and a temperature sensitive portion is not provided for the plate member. In a contact state, a partition wall provided with a temperature detection unit inserted between the plate members,
The composite heat source apparatus , wherein the index acquisition means acquires an index related to the clogging of the fins based on a result of comparing the detected temperature detected by the temperature detection unit with a predetermined threshold temperature . The composite heat source machine according to claim 2 ,
The index acquisition means compares the temperature detected by the temperature detection unit with the predetermined threshold temperature that decreases with time after switching from the simultaneous operation state to the single operation, thereby indicating an index related to the fin clogging. Combined heat source machine characterized by acquiring . In the composite heat source machine according to claim 3,
The index acquisition means relates to the clogging of the fin based on the rising speed of the detected temperature within a predetermined time after the temperature detected by the temperature detector exceeds a predetermined reference temperature after the independent operation is started. A composite heat source machine characterized by obtaining an index.

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