JP5577288B2 - Water heater - Google Patents

Description

  The present invention relates to a hot water supply apparatus, and more particularly to a hot water supply apparatus using a heat pump.

  Patent Documents 1 and 2 disclose hot water supply apparatuses. This hot water supply apparatus includes two types of heat sources, a heat pump and a combustion heat source device, and is also referred to as a hybrid hot water supply apparatus. In this type of hot water supply device, hot water heated by a heat pump is stored in a hot water storage tank, and when a large or high temperature hot water supply is required, a combustion type heat source device is configured to compensate for the shortage of heat. Has been.

  In heat pumps, frost formation is likely to occur because heat is collected from a low-temperature atmosphere. When frost formation occurs, the capacity of the heat pump is significantly reduced. Therefore, also in the conventional hot water supply apparatus, while performing the defrosting operation for removing it, monitoring the amount of frost formation of a heat pump is performed suitably (refer especially patent document 2).

JP 2009-275957 A JP 2010-249333 A

  The heat pump cannot function as a heat pump while performing the defrosting operation. That is, the hot water in the hot water storage tank cannot be heated. Therefore, if a large amount of hot water in the hot water storage tank is consumed during the defrosting operation of the heat pump, the hot water in the hot water storage tank may be exhausted. In this case, hot water supply can be continued by the combustion heat source device, but as a result of operating the combustion heat source device, the running cost is unnecessarily increased.

  In view of the above problems, the present invention provides a technique for avoiding a situation in which hot water in a hot water storage tank is exhausted during a defrosting operation of a heat pump and a combustion heat source device is operated.

  The present invention is embodied in a hot water supply apparatus. This hot water supply device includes a hot water storage tank that stores hot water, a heat pump that heats the hot water in the hot water storage tank, a combustion heat source that heats the hot water in the hot water storage tank, and a frost detection means that detects the frost formation amount of the heat pump, A defrosting unit that performs a defrosting operation of the heat pump based on the detected frost amount and the planned heat demand.

  In the hot water supply apparatus described above, whether or not the defrosting operation is necessary can be determined in consideration of not only the frost amount of the heat pump but also the planned heat demand. Thereby, for example, when a large amount of heat demand is planned, even if the amount of frost formation of the heat pump is relatively small, the defrosting operation can be executed in advance. If the defrosting operation is executed in advance, it is possible to avoid a situation where the defrosting operation is necessary when the heat pump is operated according to a large amount of heat demand.

The above-described defrosting means preferably performs the defrosting operation when the detected amount of frost formation satisfies a predetermined determination condition. In this case, it is preferable that the determination condition is changed according to the planned heat demand.
According to this configuration, when a relatively large amount of heat demand is planned, the defrosting operation can be actively performed by setting the determination condition relatively low. On the other hand, when a large amount of heat demand is not planned, the defrosting operation can be suppressed to a necessary minimum by setting the determination condition relatively high. Since the frosting of the heat pump may naturally disappear due to an increase in temperature or the like, if it can avoid the defrosting operation, the energy consumption and the emission of carbon dioxide can be reduced accordingly.

It is preferable that the above-described defrosting unit has a first determination condition and a second determination condition corresponding to a frost amount less than the first determination condition. In this case, when the detected frost amount satisfies the first determination condition, the defrosting operation is forcibly executed regardless of the planned heat demand, and the detected frost amount satisfies the second determination condition. In some cases, it is preferable to selectively execute the defrosting operation according to the planned heat demand.
In this configuration, when the detected frost formation amount satisfies the first determination condition and the amount is relatively large, the defrosting operation is forcibly executed without considering the planned heat demand. To do. On the other hand, when the detected amount of frost meets the second determination condition and the amount is relatively small, the defrosting operation is selectively executed in consideration of the planned heat demand. .

In the defrosting means described above, when the detected amount of frost formation satisfies the second determination condition, the defrosting operation may be performed when a heat demand exceeding a predetermined amount is scheduled within a predetermined time. preferable.
The predetermined heat demand here includes not only a heat demand exceeding a predetermined amount of heat but also a specific hot water supply operation that generates a relatively large amount of heat demand such as “hot water filling”. For example, when “hot water filling” is scheduled within one hour, the defrosting operation may be performed when the detected amount of frost formation satisfies the second determination condition.

It is preferable that the hot water supply apparatus according to the present invention further includes heat storage amount detection means for detecting the heat storage amount of the hot water storage tank. In this case, the defrosting means described above can calculate the planned heat storage amount of the hot water storage tank based on the detected heat storage amount, the planned heat demand, and the heating capacity of the heat pump. When the detected amount of frost formation satisfies the second determination condition described above, it is preferable that the defrosting operation is executed when the amount of heat stored in the hot water storage tank falls below a predetermined lower limit value within a predetermined time. .
In a situation where a lot of hot water is supplied unscheduled and the amount of hot water in the hot water storage tank has already decreased, even if the expected future heat demand is relatively low, the hot water storage tank will run short of heat pump operation. It may be necessary. In such a case, the defrosting operation cannot be performed in advance simply by considering the planned heat demand.
Therefore, if the current heat storage amount (or hot water amount) of the hot water storage tank is detected and the planned heat storage amount can be grasped as in the above-described configuration, the defrosting is performed prior to the timing at which the operation of the heat pump is required. Driving can be performed appropriately.

  According to the present invention, the defrosting operation of the heat pump can be executed in advance according to the anticipated heat demand, the hot water in the hot water storage tank runs out during the defrosting operation, and the auxiliary heat source device is operated. It is possible to avoid such a situation.

The figure which shows the structure of the hot water supply apparatus 10 of an Example typically. The flowchart explaining operation | movement of the hot water supply apparatus 10 of an Example. The graph which shows an example of (A) anticipated heat demand, (B) the operating condition of a heat pump, (C) frosting amount of a heat pump, and a large-scale heat demand is not planned. The graph which shows a case where it is an example of (A) anticipated heat demand, (B) the operating condition of a heat pump, (C) frost amount of a heat pump, and a large amount of heat demand (hot water filling) is planned. The modification from the flowchart shown in FIG.

  In practicing the present invention, the combustion heat source device only needs to heat hot water by burning fuel, and its specific configuration is not particularly limited. For example, the combustion heat source device may use a combustible gas such as city gas as a fuel, or may use a liquid fuel such as kerosene or a solid fuel such as charcoal. The combustion heat source may be one that heats hot water discharged from a hot water storage tank, or one that heats hot water stored in a hot water storage tank.

  In carrying out the present invention, the frost detection means is not particularly limited as long as it can detect the frost amount of the heat pump, particularly the frost amount of the evaporator. For example, since the vapor is clogged due to frost formation, the frost detection means may detect the amount of air passing through the evaporator. In this case, the frost detection means may directly detect the passing air volume of the evaporator with an air volume sensor, or by detecting the current value of the motor that drives the fan that blows air to the evaporator, The passing air volume can also be detected indirectly. Or since the efficiency of a heat pump falls by frost formation to evaporation, a frost detection means may detect the efficiency of a heat pump.

  In practicing the present invention, the heat demand storage means is not particularly limited as long as it stores at least a part of the planned heat demand. For example, the heat demand storage means may store only a scheduled time when a hot water filling operation to a bathtub is executed as a simple example. In this case, the scheduled time may be manually input by the user, or may be estimated by the hot water supply apparatus based on the past results. Or a heat demand memory | storage means may memorize | store numerically the planned heat demand by the calorie | heat amount for every unit time (for example, 30 minutes) as an example of a complicated thing. In this case, the scheduled amount of heat per unit time may be manually input by the user, or may be determined by the hot water supply apparatus based on past results. Since the user's lifestyle is often different for each day of the week, it is also effective to store the planned heat demand for each day of the week.

  In carrying out the present invention, the defrosting operation performed by the defrosting unit may be any operation that can remove frost attached to the heat pump, and the content thereof is not particularly limited. For example, the defrosting operation may operate the compressor of the heat pump after the heat supply from the heat pump to the hot water storage tank is cut off. According to this operation, frost adhering to the evaporator or the like can be melted by raising the temperature of the refrigerant of the heat pump. Or you may melt the frost adhering to an evaporator etc. by heating a refrigerant | coolant with the heat from a hot water storage tank, and circulating it.

  In practicing the present invention, some or all of the frost detection means, the heat demand storage means, and the defrosting means can be configured by one or a plurality of controllers configured by computer hardware and software.

  In practicing the present invention, the hot water supply apparatus may be a so-called hot water supply / heater apparatus having a heating function such as floor heating or bathroom heating. In this case, the hot water supply and heating device can use the heat stored in the hot water storage tank by the heat pump for the heating operation, and can appropriately compensate for the shortage of heat by the combustion heat source.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a hot water supply apparatus 10 of the present embodiment. The hot water supply apparatus 10 is an apparatus for supplying hot water to hot water supply locations such as a currant (not shown) and a bathtub. As shown in FIG. 1, the hot water supply apparatus 10 includes a heat pump unit (hereinafter, HP unit) 20, a hot water storage unit 60, a gas combustor 98, a controller 12, and a remote controller 18.

  The controller 12 includes first, second, and third controllers 12a, 12b, and 12c that are communicably connected to each other. The first controller 12 a is provided in the HP unit 20 and mainly controls the operation of the HP unit 20. The second controller 12 b is provided in the hot water storage unit 60 and mainly controls the operation of the hot water storage unit 60. The third controller 12 c is provided in the gas combustor 98 and mainly controls the operation of the gas combustor 98. The 1st, 2nd, 3rd controller 12a, 12b, 12c functions as the controller 12 which controls the whole hot-water supply apparatus 10 by cooperating. A remote controller 18 is connected to the controller 12. The remote controller 18 is disposed in the user's room and is operated by the user for turning on / off the main power supply, setting the hot water supply temperature, performing a hot water filling operation on the bathtub, and the like.

  The HP unit 20 is a heat pump that collects heat from the atmosphere. The HP unit 20 includes a compressor 32, a radiator 36, an expansion valve 28, an evaporator 24, and a refrigerant circulation path 22 that connects them in order. Further, the HP unit 20 is provided with a fan 26 that blows air to the evaporator 24 and a motor 30 that drives the fan 26. The refrigerant circulation path 22 is filled with carbon dioxide, which is a refrigerant. The refrigerant may be another refrigerant such as HFC (hydrofluorocarbon). Further, a capillary tube can be used in place of the expansion valve 28.

  The refrigerant is compressed in the compressor 32 and heated to a high temperature. The high-temperature refrigerant is sent to the radiator 36 and exchanges heat with water. The radiated refrigerant is expanded in the expansion valve 28 and cooled to a low temperature. The low-temperature refrigerant is sent to the evaporator 24 to exchange heat with the atmosphere. The evaporator 24 is a fin tube type heat exchanger. The refrigerant that has absorbed heat from the atmosphere and evaporated is sent to the compressor 32. By repeating the above cycle, the HP unit 20 can collect heat from a relatively low temperature atmosphere and heat hot water in a hot water storage tank 64 described later. The thermistors 38 and 34 detect the temperature of warm water before heating flowing into the radiator 36 and the temperature of warm water after heating flowing out of the radiator 36, respectively. The thermistors 38 and 34 are connected to the controller 12.

  The hot water storage unit 60 includes a hot water storage tank 64. The hot water storage tank 64 is an example, but can store 50 liters of hot water. The hot water storage tank 64 is provided with a plurality of thermistors 66. The plurality of thermistors 66 are connected to the controller 12. The controller 12 can grasp the amount of hot water stored in the hot water storage tank 64 from the temperature detected by each thermistor 66.

  An HP circulation path 62 is connected to the hot water storage tank 64. The HP circulation path 62 extends from the lower part of the hot water storage tank 64 to the upper part of the hot water storage tank 64 via the radiator 36 of the HP unit 20. A circulation pump 40 is provided in the HP circulation path 62. When the amount of hot water in the hot water storage tank 64 falls below a predetermined lower limit value, the controller 12 operates the HP unit 20 and operates the circulation pump 40. Thereby, hot water (cold water) in the hot water storage tank 64 is sent to the HP unit 20 and heated, and the hot water heated in the HP unit 20 is returned to the hot water storage tank 64 and stored.

  A water supply pipe 70 and a hot water discharge pipe 80 are connected to the hot water storage tank 64. The water supply pipe 70 is a pipe that supplies clean water to the hot water storage tank 64, and is connected to the bottom of the hot water storage tank 64. The water supply pipe 70 is provided with a flow rate sensor 74 for detecting the amount of clean water and a water supply thermistor 76 for detecting the temperature of clean water. The hot water discharge pipe 80 is a pipe that sends hot water from the hot water storage tank 64 to a hot water supply location, and is connected to the upper part of the hot water storage tank 64. The hot water discharge pipe 80 is provided with a first hot water thermistor 82, a first flow rate adjusting valve 84, a second hot water thermistor 86, a second flow rate adjusting valve 88, and a third hot water thermistor 90. In addition, a mixed water pipe 72 branched from the water supply pipe 70 joins in the middle of the hot water outlet pipe 80. The mixed water pipe 72 is provided with a third flow rate adjusting valve 78. Each thermistor and the flow rate adjusting valve are connected to the controller 12. The controller 12 adjusts the opening of each flow rate adjustment valve according to the detected temperature by each thermistor and the set temperature by the remote controller 18.

  A combustor circulation path 96 is connected to the hot water outlet pipe 80. The combustor circulation path 96 branches off from the hot water discharge pipe 80 and merges again with the hot water discharge pipe 80 via the gas combustor 98. The gas combustor 98 is a device that heats hot water by burning combustible gas. In the hot water supply apparatus 10 of the present embodiment, a gas combustor 98 is provided as an auxiliary heat source device. That is, when there is a request for hot water supply in a large amount or at a high temperature and the hot water amount or the hot water temperature in the hot water storage tank 64 is insufficient, the shortage of heat can be compensated by operating the gas combustor 98. Here, the amount of hot water sent to the gas combustor 98 is controlled by the second flow rate adjustment valve 88.

  As described above, the hot water supply apparatus 10 of the present embodiment includes the HP unit 20 and heats the hot water in the hot water storage tank 64 using the heat of air. At this time, the HP unit 20 collects heat from a low-temperature atmosphere, so frost formation (including icing) is likely to occur. In particular, frost formation is likely to occur in the evaporator 24. When frost formation occurs in the evaporator 24, the capacity of the HP unit 20 is significantly reduced. Therefore, in the HP unit 20 of the present embodiment, the frost amount of the evaporator 24 is detected, and the defrost operation for removing the frost (ice) of the evaporator 24 is executed according to the detected frost amount. It is configured as follows.

  However, the HP unit 20 cannot function as a heat pump while performing the defrosting operation. That is, the hot water in the hot water storage tank 64 cannot be heated. Therefore, if a large amount of hot water in the hot water storage tank 64 is consumed during the defrosting operation of the HP unit 20, the hot water storage tank 64 cannot be heated and the hot water in the hot water storage tank 64 runs out. is there. Even in such a case, the hot water supply can be continued by the gas combustor 98. However, since the gas combustor 98 is operated instead in the situation where the HP unit 20 should be operated, the running cost is unnecessarily increased.

  In view of the above problem, in the hot water supply apparatus 10 of the present embodiment, the controller 12 stores the planned heat demand, and further determines the necessity of the defrosting operation in consideration of the planned heat demand. It is configured. Although it is an example, the controller 12 of a present Example has memorize | stored the planned heat demand as a calorie | heat amount for every 30 minutes. Moreover, about the hot water filling operation, the scheduled time is separately memorize | stored as a specific operation which brings about a large amount of heat demand. Considering the planned heat demand, if a large amount of heat demand is planned, the defrosting operation can be executed in advance even if the detected amount of frost formation is relatively small. If the defrosting operation is executed in advance, it is possible to avoid a situation where the defrosting operation is required when the HP unit 20 is operated according to a large amount of heat demand. The controller 12 can update the stored heat demand schedule according to the actual heat demand.

  FIG. 2 shows a flow of the defrosting operation performed by the controller 12. Hereinafter, with reference to FIG. 2, the process which determines the necessity of a defrost operation based on the detected amount of frost formation and the planned heat demand is demonstrated in detail. Note that the processing described below is an example, and can be changed as appropriate.

  First, if the HP unit 20 is in operation (YES in step S12), the controller 12 proceeds to step S12 and detects the frost formation amount of the evaporator 24. The detection method of the amount of frost formation is not specifically limited. In this embodiment, although it is an example, in order to detect the frost formation amount of the evaporator 24, the current value flowing through the motor 30 of the HP unit 20 is detected. When frost forms on the evaporator 24, the evaporator 24 is clogged, and the substantial air flow rate of the fan 26 is reduced. As a result, the current value of the motor 30 that drives the fan 26 also decreases. Therefore, by detecting the current value of the motor 30, the frost amount of the evaporator 24 can be detected.

  In step S14, the controller 12 determines whether or not the detected frost amount exceeds the second reference value X2. The second reference value X2 corresponds to a relatively small amount of frost formation, and corresponds to a frost formation amount that does not necessarily require a defrosting operation although frost formation on the evaporator 24 is observed. If the detected amount of frost formation is equal to or less than the second reference value X2 (NO in step S14), the defrosting operation does not need to be executed, and the process returns to the first step S10. On the other hand, if the detected frost amount has reached the second reference value X2 (YES in step S14), the process proceeds to step S16 and subsequent steps. As described below, in the processing after step S16, whether or not the defrosting operation is necessary is determined in consideration of the planned heat demand.

  First, in step S16, the controller 12 confirms the stored hot water filling scheduled time, and whether the hot water filling operation is scheduled within a predetermined time (can be set or changed to 1 hour in this embodiment). Confirm whether or not. When the hot water filling operation is scheduled (YES in step S16), the process proceeds to step S24, and the defrosting operation is executed. In hot water filling operation, a large amount of hot water exceeding the capacity of the hot water storage tank 64 is consumed. Accordingly, the HP unit 20 is always operated during the filling operation. Therefore, when the hot water filling operation is started soon, the defrosting operation is performed in advance, so that the defrosting operation is necessary during the hot water filling operation (that is, the amount of frost formation is the first reference). The situation of reaching the value X1 is avoided. On the other hand, when the hot water filling operation is not scheduled within the predetermined time (NO in step S16), the process proceeds to step S18.

  Next, in step S18, the controller 12 determines whether or not a large amount of heat demand exceeding a predetermined amount is scheduled within a predetermined time (in the present embodiment, can be set and changed to one hour). As described above, the controller 12 stores the planned heat demand by the amount of heat every 30 minutes. The controller 12 verifies the stored time-series data of the heat demand, and when the planned heat demand amount within a predetermined time exceeds the predetermined amount (YES in Step S18), the controller 12 proceeds to Step S24 and performs the defrosting operation. Execute. When a large amount of heat demand occurs, the hot water in the hot water storage tank 64 is greatly consumed, so that the possibility of operating the HP unit 20 is very high. Therefore, when a large amount of heat demand is scheduled in the near future, the defrosting operation is performed in advance while the hot water storage tank 64 is being boiled, so that the defrosting operation is required (that is, the defrosting operation is performed). The situation where the amount of frost reaches the first reference value X1) is avoided. On the other hand, if a large amount of heat demand is not scheduled within the predetermined time (NO in step S18), the process proceeds to step S20.

  Next, in step S20, the controller 12 calculates the planned heat storage amount of the hot water storage tank 64, and the predetermined heat storage amount of the hot water storage tank 64 is set to a predetermined time (in this embodiment, 1 hour can be set or changed). It is determined whether or not it falls below a predetermined lower limit value. In a situation where a lot of hot water is supplied unscheduled and the amount of hot water in the hot water storage tank 64 has already decreased, the amount of hot water in the hot water storage tank 64 decreases to the lower limit even if the planned future heat demand is relatively small. The operation of the HP unit 20 may be necessary. Therefore, when such a situation is expected (YES in step S20), the process proceeds to step S24, and the defrosting operation is performed in advance. The planned heat storage amount of the hot water storage tank 64 can be calculated from the current heat storage amount (hot water amount) of the hot water storage tank 64, the planned heat demand, and the heating capacity of the HP unit 20. On the other hand, when the planned heat storage amount of the hot water storage tank 64 does not fall below the predetermined lower limit (NO in step S20), the process proceeds to step S22.

  Next, in step S22, the controller 12 determines whether or not the frost amount detected in step S12 exceeds the first reference value X1. Here, the first reference value X1 corresponds to a larger amount of frost formation than the second reference value X2, and is a level that greatly reduces the capacity of the HP unit 20, and the defrosting operation should be executed immediately. It corresponds to the amount of frost formation. Therefore, when the detected amount of frost formation exceeds the first reference value X1 (YES in step S22), the process proceeds to step S24, and the defrosting operation is immediately executed. Thus, if the detected frost amount exceeds the first reference value X1, the defrosting operation is executed regardless of the planned heat demand. On the other hand, if the detected amount of frost formation is equal to or less than the first reference value X1 (NO in step S22), the process returns to the first step S10 without performing the defrosting operation. Thus, the flow related to the defrosting operation is completed.

  3 and 4 are time charts illustrating the timing at which the defrosting operation is executed. 3 and 4, (A) shows the planned heat demand, (B) shows the operation status of the HP unit 20, and (C) shows the frost formation amount of the HP unit 20. As shown in FIG. 3, there is little planned heat demand in the time zone from midnight to early morning. In such a time zone, the defrosting operation is appropriately performed when the frosting amount of the HP unit 20 exceeds the first reference value X1. On the other hand, as shown in FIG. 4, in the time zone from evening to midnight, there is much planned heat demand, and hot water operation is also scheduled. In such a time zone, the defrosting operation is performed in advance when the amount of frost formation of the HP unit 20 exceeds the second reference value X2 prior to the time when a large amount of heat demand or hot water operation is scheduled. . Thereby, it is possible to avoid performing the defrosting operation in a time zone (8:00 pm to 10:00 pm) in which a large amount of heat demand or hot water filling operation is performed.

  Here, when determining whether or not the defrosting operation is necessary, the controller 12 of the present embodiment takes into consideration the planned heat demand through the three steps S16, S18, and S20, but the three steps S16, S18, and S20. Is not necessarily required. In order to simplify the configuration of the hot water supply apparatus 10, only one or two of the three steps S16, S18, and S20 may be executed. That is, when determining whether or not the defrosting operation is necessary, only the scheduled time of filling operation may be considered as the planned heat demand (step S16), or only a large amount of heat demand may be considered. It may be good (step S18), or only the planned heat storage amount (hot water amount) of the hot water storage tank 64 may be considered (step S20).

  The controller 12 of this embodiment operates the HP unit 20 with the circulation pump 40 stopped as a defrosting operation. Thereby, the temperature of the refrigerant of the HP unit 20 can be raised, and frost (ice) adhering to the evaporator 24 and the like can be melted. Note that the defrosting operation of the HP unit 20 is not limited to this example, and may be performed by other methods.

  When performing the defrosting operation in consideration of the planned heat demand (YES in step S16, S18, or S20), the timing for performing the defrosting operation may be determined according to the planned heat demand. . That is, since the timing at which the HP unit 20 operates can be estimated from the planned heat storage amount (hot water amount) of the hot water storage tank 64, the defrosting operation is started so that the defrosting operation is completed by that timing. The timing may be adjusted.

  The flow of the defrosting operation shown in FIG. 2 can be changed as appropriate. For example, as shown in FIG. 5, the determination of the frost amount based on the first reference value X1 (step S22) may be executed before the determination of the frost amount based on the second reference value X2 (step S14). . In this aspect, when the amount of frost on the evaporator 24 is very large and the defrosting operation is indispensable regardless of the planned heat demand, the process considering the planned heat demand (steps S16, S18, The defrosting operation can be executed by omitting S20). Thereby, the arithmetic processing performed by the controller 12 can be reduced.

  As mentioned above, although the Example of this invention was described in detail, these are only illustrations and do not limit a claim. The technology described in the claims includes various modifications and changes of the specific examples illustrated above.

  The technical elements described in this specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology exemplified in this specification or the drawings can achieve a plurality of objects at the same time, and achieving one of the objects itself has technical utility.

10: hot water supply device 12: controller 12a: controller 12b: controller 12c: controller 18: remote controller 20: HP unit 22: refrigerant circulation path 24: evaporator 26: fan 28: expansion valve 30: motor 32: compressor 36: radiator 38: Thermistor 40: Circulation pump 60: Hot water storage unit 62: HP circulation path 64: Hot water storage tank 66: Thermistor 70: Water supply pipe 72: Mixed water pipe 74: Flow rate sensor 76: Water supply thermistor 78: Third flow rate adjustment valve 80: Hot water supply pipe 82: First hot water thermistor 84: First flow rate adjusting valve 86: Second hot water thermistor 88: Second flow rate adjusting valve 90: Third hot water thermistor 96: Combustor circulation path 98: Gas combustor

Claims (2)

A hot water storage tank for storing hot water,
A heat pump that heats the hot water in the hot water storage tank;
A combustion heat source for heating hot water in a hot water storage tank;
Frost detection means for detecting the amount of frost formation of the heat pump;
Heat demand storage means for storing planned heat demand;
Defrosting means for performing a defrosting operation of the heat pump based on the detected amount of frost formation and the planned heat demand,
The defrosting unit has a first determination condition and a second determination condition corresponding to a frost amount less than the first determination condition,
When the detected amount of frost formation satisfies the first determination condition, the defrosting operation is forcibly executed regardless of the planned heat demand,
When the detected frost amount and the second determination condition is satisfied, when it is expected heat demand exceeds a predetermined amount within a predetermined time, feed water you wherein defrosting operation is performed apparatus. A hot water storage tank for storing hot water,
A heat pump that heats the hot water in the hot water storage tank;
A combustion heat source for heating hot water in a hot water storage tank;
Frost detection means for detecting the amount of frost formation of the heat pump;
Heat demand storage means for storing planned heat demand;
Defrosting means for performing a defrosting operation of the heat pump based on the detected amount of frost formation and the planned heat demand,
The defrosting means can calculate the planned heat storage amount of the hot water storage tank based on the detected heat storage amount and the planned heat demand and the heating capacity of the heat pump.
The defrosting unit has a first determination condition and a second determination condition corresponding to a frost amount less than the first determination condition,
When the detected amount of frost formation satisfies the first determination condition, the defrosting operation is forcibly executed regardless of the planned heat demand,
When the detected amount of frost formation satisfies the second determination condition, the defrosting operation is performed when the planned heat storage amount of the hot water storage tank falls below a predetermined lower limit value within a predetermined time. hot water supply apparatus you.

Images