JP5902126B2 - Combustion equipment - Google Patents

Description

  The present invention relates to a combustion apparatus that burns a mixed gas of fuel gas and combustion air.

  A hot water supply device and a heating device are equipped with a combustion device that burns a mixed gas of fuel gas and combustion air with a burner. In order to properly burn the mixed gas with this combustion device, the fuel gas and the combustion air must be mixed at an appropriate ratio (air-fuel ratio), so that the fuel gas depends on the amount of heat required for hot water supply and heating. The supply amount of the combustion air and the supply amount of the combustion air are controlled.

  Immediately after starting (igniting) combustion with such a combustion device, the combustion chamber containing the burner is not warm (it is in a cold state), so the combustion speed relative to the supply speed of the mixed gas in the burner compared to the warm state However, the flame tends to float from the burner (so-called lift) and the combustion tends to become unstable. Therefore, it has been proposed to stabilize combustion by increasing the combustion rate by increasing the fuel gas ratio higher than the normal air-fuel ratio for a certain period after the start of combustion (Patent Document 1).

JP-A-8-261445

  However, in the proposed technology, even when combustion is started in a state where the combustion chamber is warm (when combustion is restarted), the ratio of the fuel gas becomes high, and the combustion speed increases, so that backfire is likely to occur. In addition, there was a problem of wasteful consumption of fuel gas. Of course, it is possible to detect the temperature by providing a temperature sensor in the combustion chamber. However, in a combustion chamber that houses multiple unit burners, the temperature sensor detects the temperature of the installation location, while the combustion location is switched variously and the combustion range is changed depending on the amount of heat required. Therefore, it cannot be said that the detected temperature is representative of the entire combustion chamber, and the air-fuel ratio cannot be appropriately controlled according to the temperature state (warming condition) in the combustion chamber.

  The present invention has been made in response to the above-described problems in the prior art, and an object thereof is to provide a technique capable of appropriately controlling the air-fuel ratio according to the temperature state in the combustion chamber and stabilizing the combustion. To do.

In order to solve the above-described problems, the combustion apparatus of the present invention employs the following configuration. That is,
At least one of a combustion chamber for storing a burner, a fuel gas supply means for supplying fuel gas to the burner, a combustion air supply means for supplying combustion air to the burner, and the fuel gas and the combustion air In a combustion apparatus comprising: control means for controlling a supply amount; an intake passage for guiding the combustion air toward the combustion chamber; and an exhaust passage for guiding combustion exhaust discharged from the combustion chamber;
Differential pressure acquisition means for acquiring a differential pressure that is a difference between the pressure in the air supply passage and the pressure in the exhaust passage;
The combustion air supply means executes pre-supply for supplying the combustion air prior to ignition by the burner,
The control means corrects the supply amount of at least one of the fuel gas and the combustion air at the time of ignition by the burner based on the differential pressure during the preliminary supply.

  The air-fuel ratio (ratio of the supply amount of fuel gas and combustion air) appropriate for stable combustion immediately after ignition by the burner in the combustion chamber varies depending on the temperature state (warming condition) in the combustion chamber. In the combustion apparatus of the present invention, in order to determine the temperature state in the combustion chamber, the temperature in the supply passage (supply pressure) and the pressure in the exhaust passage (exhaust pressure) are not directly detected by a temperature sensor. Pressure difference). In general, when a gas (combustion air or combustion exhaust gas) passes through a combustion chamber, an exhaust pressure is lower than a supply air pressure due to a passage resistance. Further, in a state where the combustion chamber is warm as compared with a state where the combustion chamber is cold, the gas is warmed while passing through and tends to expand, so that the exhaust pressure increases and becomes close to the supply pressure (the differential pressure decreases). . In this way, the differential pressure between the supply pressure and the exhaust pressure is different from detecting the local temperature with the temperature sensor, and changes on behalf of the overall temperature state of the combustion chamber. By acquiring the differential pressure during supply and correcting the supply amount of at least one of fuel gas and combustion air at the time of ignition based on the differential pressure, the air / fuel ratio is controlled to an appropriate air / fuel ratio according to the temperature state in the combustion chamber. Thus, combustion can be stabilized from the time of ignition.

  In the combustion apparatus of the present invention described above, the supply amount of at least one of the fuel gas and the combustion air during the period from the ignition by the burner to the stabilization of the differential pressure may be corrected based on the differential pressure.

  Even after the combustion is started (ignited) by the burner, the combustion state until the combustion chamber is warmed (differential pressure is stabilized) tends to be easily affected by the temperature state (warming condition) in the combustion chamber. Therefore, during this time, if the supply amount of at least one of the fuel gas and the combustion air is corrected based on the differential pressure, the combustion can be stabilized by controlling to an appropriate air-fuel ratio.

  In such a combustion apparatus of the present invention, when the differential pressure is less than the reference value, the ratio of the fuel gas supply amount to the combustion air supply amount may be made lower than when the differential pressure is greater than the reference value.

  If the differential pressure is large (over the reference value), it can be judged that the combustion chamber is not warm (it is in a cold state), and the flame tends to be lifted and combustion tends to be more unstable than in the warm state. It is in. In this case, by setting the fuel gas ratio high (combustion air ratio low), the lift can be suppressed and combustion can be stabilized. On the other hand, when the differential pressure is small (below the reference value), it can be determined that the combustion chamber is warm, and if the fuel gas ratio is set high, backfire is likely to occur and the combustion state may be worsened. There is. Therefore, if the ratio of the fuel gas is set lower than when the differential pressure is large, it is possible to suppress wasteful consumption of the fuel gas and to stably burn at an appropriate air-fuel ratio.

  In the combustion apparatus of the present invention, the temperature of the combustion air (supply temperature) in the supply passage is detected, and at least one of the fuel gas and the combustion air is determined based on the differential pressure and the supply temperature. The supply amount may be corrected.

  When the supply air temperature changes, the density of the combustion air supplied to the burner changes. For example, if the supply air temperature decreases, the density of combustion air increases, so if the supply amount of combustion air is controlled by volume flow rate, the mass flow rate increases even if the same supply amount is set. As a result, the combustion air becomes excessive. Therefore, if the supply amount of at least one of fuel gas and combustion air is corrected based on not only the differential pressure but also the supply air temperature, the air-fuel ratio can be controlled more appropriately by taking into account changes in the density of the supplied combustion air. can do.

It is explanatory drawing which shows the internal structure of the warm air heater 1 carrying the combustion apparatus 100 of a present Example. It is a flowchart of the combustion control process of a present Example. It is explanatory drawing which showed a mode that differential pressure | voltage changes with the state in which the inside of the combustion chamber 104 was cooled, and the warmed state. It is explanatory drawing which showed the correspondence of the differential pressure | voltage and the correction coefficient of gas amount in a 1st modification. It is a flowchart of the air temperature reference process of a 2nd modification.

  FIG. 1 is an explanatory diagram showing the internal structure of a hot air heater 1 equipped with a combustion apparatus 100 of the present embodiment. The hot air heater 1 includes a housing 10 that covers the whole, a combustion device 100, a blower fan 140 that generates an air flow in the housing 10, and the like.

  The combustion apparatus 100 supplies a fuel gas to the burner 102 that burns a mixed gas of fuel gas and combustion air, a combustion chamber 104 that houses the burner 102, an ignition plug 106 that ignites the mixed gas, and the burner 102. A gas passage 108, a supply passage 110 that takes in combustion air from outside and leads it to the burner 102 of the combustion chamber 104, a heat exchange section 112 that guides combustion exhaust from the combustion chamber 104 and meanders in the housing 10, An exhaust passage 114 that guides the combustion exhaust gas that has passed through the heat exchange unit 112 to the outside is provided. Note that the air supply passage 110 and the exhaust passage 114 are integrated with a portion projecting indoors to the outdoors, and have a double pipe structure in which the exhaust passage 114 is formed inside the air supply passage 110.

  The burner 102 includes a plurality of unit burners 103 that mix fuel gas and combustion air and eject the mixed gas. The gas passage 108 is provided with an electromagnetic valve 116 that opens and closes the gas passage 108 and a proportional valve 118 that controls the flow rate of the fuel gas passing through the gas passage 108. In addition, the supply air passage 110 is provided with a supply air pressure sensor 120 that detects a pressure in the supply air passage 110 (hereinafter referred to as supply air pressure) and a temperature of combustion air that passes through the supply air passage 110 (hereinafter referred to as supply air temperature). An air temperature sensor 122 for detection is provided. Further, in the exhaust passage 114, a negative pressure is generated to suck out combustion exhaust from the combustion chamber 104, and the combustion fan 124 for sucking combustion air in the supply passage 110 into the combustion chamber 104 and the combustion fan 124 are driven to rotate. An exhaust pressure sensor 128 that detects the pressure in the exhaust passage 114 (hereinafter referred to as exhaust pressure) is provided on the side closer to the combustion chamber 104 than the combustion fan 124.

  The combustion apparatus 100 also includes a controller 150 that controls the operation of the ignition plug 106, the electromagnetic valve 116, the proportional valve 118, and the combustion fan motor 126. The controller 150 includes the air pressure sensor 120 and the air temperature sensor 122. The detection signal of the exhaust pressure sensor 128 is input.

  In this embodiment, the solenoid valve 116 and the proportional valve 118 for supplying fuel gas to the burner 102 correspond to the “fuel gas supply means” of the present invention, and the combustion fan 124 for supplying combustion air is provided. The controller 150 that controls the operation of the solenoid valve 116, the proportional valve 118, and the combustion fan 124 corresponds to the “control means” of the present invention. Further, the air temperature sensor 122 for detecting the air temperature corresponds to the “air temperature detecting means” of the present invention.

  The blower fan 140 employs a so-called cross flow fan, and is provided with a blower fan motor 142 for rotationally driving the fan. The operation of the blower fan motor 142 is also controlled by the controller 150. When the blower fan 140 is rotated, the indoor air sucked from the suction port 144 provided in the upper portion of the housing 10 is heated by the heat exchanging unit 112 while passing through the housing 10, thereby lowering the lower portion of the housing 10. Warm air blows out from the air outlet 146 provided in the.

  In such a warm air heater 1, a necessary amount of heat is determined based on a temperature set by the user, and the proportional valve 118 is opened in order to appropriately burn the mixed gas in the burner 102 according to the determined amount of heat. The fuel gas supply amount is controlled by adjusting the degree, and the rotation speed of the combustion fan 124 is adjusted to control the combustion air supply amount. Below, the process (combustion control process) which the controller 150 performs in order to make it burn stably with the burner 102 is demonstrated. In this embodiment, the ratio of the supply amount of fuel gas and combustion air is called the air-fuel ratio.

  FIG. 2 is a flowchart of the combustion control process of the present embodiment. This process is executed when an operation switch (not shown) is turned on by the user of the hot air heater 1. In the combustion control process, first, the rotation of the combustion fan 124 is started and set to a predetermined initial rotation speed (STEP 100). At this point, fuel gas is not supplied or ignited. The operation of rotating the combustion fan 124 before ignition in this way is called pre-purge and corresponds to “pre-supply” of the present invention.

  When the combustion fan 124 reaches the initial rotation speed, a pressure obtained by subtracting the exhaust pressure from the supply air pressure (hereinafter referred to as differential pressure) is acquired (STEP 102). As the air pressure sensor 120 and the exhaust pressure sensor 128, a semiconductor pressure sensor whose resistance value changes according to pressure is used, and a differential pressure is detected based on its output. If the air pressure sensor 120 and the exhaust pressure sensor 128 are clogged at some point, the differential pressure becomes abnormally large, so that the clogging can be detected. Further, in the combustion apparatus 100 of the present embodiment, the temperature state (warming condition) in the combustion chamber 104 is determined based on this differential pressure. The controller 150 according to the present embodiment acquires the differential pressure based on the outputs of the supply air pressure sensor 120 and the exhaust pressure sensor 128, and thus corresponds to the “differential pressure acquisition unit” of the present invention.

  FIG. 3 shows how the differential pressure changes between a state in which the combustion chamber 104 is cooled and a state in which the combustion chamber 104 is warm. The cold state is a state in which time has elapsed after the combustion in the burner 102 is completed and the temperature has returned to room temperature. The warm state is a state in which the combustion in the burner 102 is performed for a certain period of time. It is assumed that it is in a heated state. In the combustion apparatus 100 of the present embodiment, a negative pressure is generated by the combustion fan 124 provided in the exhaust passage 114 to suck out combustion exhaust from the combustion chamber 104, and suck combustion air into the combustion chamber 104 from the supply passage 110. A negative pressure type is adopted, and when the combustion air passes through the combustion chamber 104, a passage resistance is generated, so that the exhaust pressure is smaller (negative pressure) than the supply air pressure. In the state where the combustion chamber 104 is cooled, the temperature of the combustion air does not greatly change (warm up) while the combustion air sucked from the air supply passage 110 passes through the combustion chamber 104. In this example, a differential pressure of 250 Pa is generated.

  On the other hand, in the state in which the combustion chamber 104 is warm, the exhaust air pressure is increased because the combustion air is warmed while passing through the combustion chamber 104 as compared with the state in which the combustion chamber 104 is cold. As a result, the differential pressure is reduced to 185 Pa. As described above, the differential pressure changes on behalf of the temperature state of the combustion chamber 104 as a whole. Therefore, in the combustion apparatus 100 of the present embodiment, the local temperature is not detected by a temperature sensor or the like. The amount of fuel gas supplied (hereinafter referred to as gas amount) is controlled by adjusting the opening degree of the proportional valve 118 while judging the temperature state in the combustion chamber 104 based on the pressure.

  In the combustion control process of FIG. 2, when the differential pressure is acquired in STEP 102, it is determined whether or not the differential pressure is larger than the initial reference value (STEP 104). Here, the initial reference value is a reference value for determining the temperature state (warming condition) in the combustion chamber 104 based on the differential pressure before the start of combustion (during pre-purge), and is set to 220 Pa in the present embodiment. Has been.

  When the differential pressure is larger than the initial reference value (STEP 104: yes), it is determined that the combustion chamber 104 is not warmed, and correction is performed to increase the gas amount by 10% with respect to the ignition standard gas amount (STEP 106). This standard gas amount at the time of ignition is a gas amount that can be ignited stably when the inside of the combustion chamber 104 is warm. When the combustion chamber 104 is not warmed, the flame tends to lift from the burner 102 as compared with the warmed state, and the combustion tends to become unstable. Therefore, by increasing the gas amount to increase the ratio of the fuel gas in the mixed gas, it is possible to suppress lift and stabilize combustion. As a result, combustion can be performed at an appropriate air-fuel ratio from the time of ignition.

  When the gas amount is set in this manner, the combustion fan 124 is rotated at a rotation speed corresponding to the ignition standard gas amount to send combustion air to the burner 102, and the solenoid valve 116 and the proportional valve 118 are opened to set the gas amount. Then, ignition is performed using the spark plug 106, and combustion of the mixed gas is started by the burner 102 (STEP 108).

  Thereafter, the differential pressure is acquired again (STEP 110), and it is determined whether or not the acquired differential pressure is larger than the reference value (STEP 112). This reference value is a value that serves as a reference for determining the temperature state in the combustion chamber 104 based on the differential pressure during combustion, and is determined according to the rotational speed of the combustion fan 124. When the differential pressure is larger than the reference value (STEP 112: yes), it is determined that the inside of the combustion chamber 104 has not yet been warmed, and the process returns to STEP 110 to enter a standby state while confirming the differential pressure.

  When the differential pressure becomes equal to or lower than the reference value (STEP 112: no), it is determined that the combustion chamber 104 has been warmed, and it is not necessary to increase the ratio of the fuel gas in the mixed gas. Is changed to the standard gas amount (STEP 114). The standard gas amount is a gas amount during normal operation that is determined according to a temperature set by the user (a necessary amount of heat). Note that the rotational speed of the combustion fan 124 is set to a rotational speed corresponding to the standard gas amount as the gas amount is changed. Thus, even after the combustion is started by the burner 102, the gas amount is changed while judging the temperature state in the combustion chamber 104 based on the differential pressure, so that the ratio of the fuel gas is maintained high even though it is not necessary. There is no such thing, and the air-fuel ratio can be controlled appropriately.

  When the gas amount is set to the standard gas amount, it is determined whether or not to end the combustion (STEP 120). In STEP 120, the end of combustion is determined based on whether or not the operation switch is turned off by the user of the hot air heater 1. When the combustion is not finished (STEP 120: no), the process returns to STEP 114 and enters a standby state while changing to the standard gas amount determined according to the temperature set by the user. When the combustion ends (STEP 120: yes), the solenoid valve 116 and the proportional valve 118 are closed to stop the supply of the fuel gas, and the rotation of the combustion fan 124 is stopped (STEP 122), and the combustion control process is performed. finish.

  The case where the differential pressure is larger than the initial reference value in the determination of STEP 104 has been described above. However, if the differential pressure is equal to or less than the initial reference value (STEP 104: no), the combustion chamber 104 is warmed. Judgment is made and the gas amount is set to the standard gas amount at the time of ignition (STEP 116). Then, the combustion fan 124 is rotated at a rotational speed corresponding to the standard gas amount at the time of ignition, and the combustion air is supplied to the burner 102 while supplying a set amount of fuel gas to ignite with the spark plug 106, Combustion of the mixed gas is started by the burner 102 (STEP 118). When resuming combustion, the combustion chamber 104 may already be warmed even at the start of combustion. In this case, if the ratio of the fuel gas in the mixed gas is increased, backfire is likely to occur. The combustion state in the burner 102 may be worsened. Therefore, if the standard gas amount at ignition is set without correcting the gas amount, wasteful consumption of fuel gas is suppressed, and the gas is stabilized at an appropriate air-fuel ratio according to the temperature state in the combustion chamber 104. Can be burned.

  The combustion apparatus 100 of the present embodiment described above includes the following modifications. In the following, modifications will be described focusing on differences from the above-described embodiment.

  In the above-described embodiment, if the differential pressure is larger than the initial reference value, correction is performed to increase the gas amount by 10%, and if the differential pressure is equal to or less than the initial reference value, correction is not performed. However, instead of providing the initial reference value, a gas amount correction amount (correction coefficient) may be set according to the acquired differential pressure. In the combustion apparatus 100 of the first modification, the correspondence relationship between the differential pressure and the gas amount correction coefficient is stored in advance in a memory (not shown) of the controller 150.

  FIG. 4 shows the correspondence between the differential pressure and the gas amount correction coefficient in the first modification. In the illustrated example, the correction coefficient is set to 1.0 (no correction) so that the gas amount becomes the ignition standard gas amount when the differential pressure is 185 Pa. Further, the correction coefficient is set to 1.1 so that when the differential pressure is 250 Pa, the gas amount increases by 10% with respect to the ignition standard gas amount. When the acquired differential pressure is between 185 Pa and 250 Pa, a correction coefficient corresponding to the differential pressure can be obtained by interpolation calculation from these two correction coefficients.

  In the combustion apparatus 100 of the first modification, the correction coefficient (> 1.0) obtained in this way is corrected to a gas amount obtained by multiplying the ignition standard gas amount. Thus, if the gas amount is finely corrected according to the differential pressure, the difference in the temperature state (warming condition) in the combustion chamber 104 can be appropriately reflected in the air-fuel ratio, so that the air-fuel ratio is controlled more appropriately. It becomes possible. Moreover, useless fuel gas consumption can be further reduced.

  In the above-described embodiment, the gas amount is controlled based on the differential pressure. However, the gas amount may be controlled based not only on the differential pressure but also on the air supply temperature (the temperature of the combustion air supplied to the combustion chamber 104). In the combustion apparatus 100 of the second modification, in order to refer to the supply air temperature during the combustion control process, the following supply air temperature reference process is executed.

  FIG. 5 is a flowchart of the air temperature reference process of the second modification. This process is inserted after STEP 106 and STEP 116 of the combustion control process (FIG. 2). As shown in the drawing, in the air temperature reference process, first, the air temperature is detected (STEP 130). The air temperature sensor 122 provided in the air supply passage 110 includes a thermistor (not shown) whose resistance value changes according to a temperature change, and detects the air temperature based on the output. Subsequently, it is determined whether or not the detected supply air temperature is lower than a specified temperature (STEP 132). In the second modification, the specified temperature is set to 10 ° C., and when the supply air temperature is equal to or higher than the specified temperature (STEP 132: no), the set gas amount is maintained without correcting the gas amount ( (STEP 134), the process returns to the combustion control process.

  On the other hand, when the supply air temperature is lower than the specified temperature (STEP 132: yes), correction is performed to increase the set gas amount by 5% (STEP 136). When the air supply temperature is lowered, the density of the combustion air supplied to the burner 102 of the combustion chamber 104 is increased, so that the mass flow rate of the combustion air is increased even if the rotational speed of the combustion fan 124 is the same. As a result, the combustion air becomes excessive. Therefore, when the supply air temperature is low (below the specified temperature), if the correction is made to increase the amount of gas compared to the case where the supply air temperature is high (above the specified temperature), the change in the density of the combustion air is taken into account. Thus, the air-fuel ratio can be controlled more appropriately.

  In the second modification described above, the case where the correction for increasing the gas amount is performed and the case where the correction is not performed are made depending on whether the supply air temperature is lower than the specified temperature. However, instead of setting the specified temperature, the correction amount (correction coefficient) may be determined so as to increase the gas amount as the detected air supply temperature decreases. For example, the correction coefficient when the supply air temperature is 20 ° C. is set to 1.0 (no correction), the correction coefficient when the supply air temperature is −10 ° C. is set to 1.05, and interpolation calculation is performed from these two correction coefficients. A correction coefficient corresponding to the detected air supply temperature may be obtained and set to the gas amount corrected with the obtained correction coefficient. As a result, the gas amount can be finely corrected according to the change in the supply air temperature, so that the air-fuel ratio can be controlled with higher accuracy.

  Although the combustion apparatus 100 of the present embodiment and the modified example has been described above, the present invention is not limited to the above-described embodiment and modified example, and can be implemented in various modes without departing from the gist thereof. It is.

  For example, in the above-described embodiments and modifications, the gas amount (the opening degree of the proportional valve 118) is corrected in order to obtain an appropriate air-fuel ratio. However, instead of the gas amount or together with the gas amount, combustion is performed. The rotational speed of the fan 124 (combustion air supply amount) may be corrected.

  In the above-described embodiment, the gas amount at the time of starting combustion (at the time of ignition) by the burner 102 is controlled based on the differential pressure, but is not limited to the time at the time of ignition. For example, in a combustion apparatus 100 including a plurality of unit burners 103, the number of unit burners 103 that perform combustion may be switched in accordance with a change in the amount of heat required during combustion. Since the required amount of gas (appropriate air-fuel ratio) is different between the state in which the unit burner 103 that newly starts combustion is cold and the state in which it is warm, the unit burner 103 that performs combustion is switched (increased). The gas amount may be controlled based on the differential pressure.

  Further, in the above-described embodiment, a negative pressure is generated by generating a negative pressure by the combustion fan 124 provided in the exhaust passage 114 and sucking the combustion exhaust from the combustion chamber 104 and sucking combustion air from the supply passage 110 into the combustion chamber 104. However, as a combustion fan 124 is provided in the supply passage 110, a positive pressure method is adopted in which combustion air is pushed into the combustion chamber 104 from the supply passage 110 and combustion exhaust is pushed out from the combustion chamber 104. Also good.

  Further, the supply air pressure and the exhaust pressure do not necessarily need to be detected individually. For example, if the supply air passage 110 and the exhaust passage 114 are connected via a differential pressure gauge, the differential pressure between the supply air pressure and the exhaust pressure is determined. May be detected directly. In this case, the differential pressure gauge corresponds to the “differential pressure acquisition means” of the present invention.

  Moreover, although the Example mentioned above demonstrated the example which mounted the combustion apparatus 100 in the warm air heater 1, the application scene of the combustion apparatus 100 is not restricted to the warm air heater 1, It is suitable also for a hot-water supply apparatus etc. Can be applied.

DESCRIPTION OF SYMBOLS 1 ... Hot air heater, 10 ... Housing, 100 ... Combustion apparatus,
102 ... Burner, 103 ... Unit burner, 104 ... Combustion chamber,
106 ... Spark plug, 108 ... Gas passage, 110 ... Air supply passage,
112 ... Heat exchange part, 114 ... Exhaust passage, 116 ... Solenoid valve,
118 ... Proportional valve, 120 ... Air pressure sensor, 122 ... Air temperature sensor,
124 ... combustion fan, 126 ... combustion fan motor, 128 ... exhaust pressure sensor,
140 ... Blower fan, 142 ... Blower fan motor, 144 ... Suction port,
146 ... outlet, 150 ... controller.

Claims (4)

At least one of a combustion chamber for storing a burner, a fuel gas supply means for supplying fuel gas to the burner, a combustion air supply means for supplying combustion air to the burner, and the fuel gas and the combustion air In a combustion apparatus comprising: control means for controlling a supply amount; an intake passage for guiding the combustion air toward the combustion chamber; and an exhaust passage for guiding combustion exhaust discharged from the combustion chamber;
Differential pressure acquisition means for acquiring a differential pressure that is a difference between the pressure in the air supply passage and the pressure in the exhaust passage;
The combustion air supply means executes pre-supply for supplying the combustion air prior to ignition by the burner,
The control unit corrects the supply amount of at least one of the fuel gas and the combustion air at the time of ignition by the burner based on the differential pressure during the preliminary supply. The combustion apparatus according to claim 1, wherein
The control means corrects the supply amount of at least one of the fuel gas and the combustion air from the ignition by the burner until the differential pressure becomes stable based on the differential pressure. Combustion device. The combustion apparatus according to claim 1 or 2,
When the differential pressure is less than a reference value, the control means lowers the ratio of the supply amount of the fuel gas to the supply amount of the combustion air than when the differential pressure is not less than the reference value. Combustion device. The combustion apparatus according to any one of claims 1 to 3,
Further comprising a supply air temperature detecting means for detecting a supply air temperature that is the temperature of the combustion air in the supply air passage;
The control unit corrects the supply amount of at least one of the fuel gas and the combustion air based on the differential pressure and the supply air temperature detected by the supply air temperature detection unit.

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