JP6375792B2 - Heat pump water heater - Google Patents

Description

  The present invention relates to a heat pump type water heater.

  When a conventional heat pump type hot water heater performs a boiling operation during the midnight power hours, the end time of the midnight power hours is to prevent the temperature drop of the hot water in the hot water tank due to heat dissipation after the boiling operation as much as possible. The start time of the boiling operation is determined so that the boiling operation is completed (see, for example, Patent Document 1). For this reason, conventionally, when the boiling operation is performed in the midnight power time zone, the boiling operation is always performed in the time zone on the end time side in the midnight power time zone.

JP 2007-285659 A

  The heat pump device included in the heat pump water heater compresses the refrigerant to high temperature and high pressure with a compressor during boiling operation, and also exchanges heat between the outside air and the refrigerant in an evaporator (air refrigerant heat exchanger) to convert the outside air into the refrigerant. It absorbs heat. In addition, the outside air temperature during the late-night power hours from midnight to early morning decreases as it goes from midnight to early morning, and becomes the lowest at dawn and early morning before sunrise.

  For this reason, in the conventional heat pump type hot water heater described above, since the boiling operation is performed in the time zone on the end time side where the outside air temperature is low in the midnight power time zone, the heat absorption amount from the outside air to the refrigerant is small, and the heat pump device There is a problem of poor operating efficiency.

  Further, in the above-described conventional heat pump type hot water heater, the boiling operation is not performed when hot water having a heat amount equal to or greater than a predetermined value remains in the hot water storage tank in the time zone on the start time side in the midnight power time zone.

  However, even when hot water having a heat quantity equal to or greater than a predetermined value remains in the hot water storage tank, the hot water temperature in the hot water storage tank is lower than that immediately after boiling due to heat dissipation. For this reason, when the user uses the hot water in the hot water storage tank as it is without adjusting the temperature in the time zone on the start time side of the midnight power time zone, there is a problem that the user's feeling of use is bad. For example, when the bath is reheated using the heat of the hot water in the hot water storage tank, the hot water temperature in the hot water tank is lower than that immediately after boiling. Will become longer.

  In view of the above points, the present invention is a heat pump type that can perform a boiling operation with higher operating efficiency than the conventional one, and can improve the user's feeling when using hot water in a hot water storage tank in the late-night power hours. The purpose is to provide a water heater.

In order to achieve the above object, in the invention described in claim 1,
A heat pump device (10) operated by electric power and boiling water,
A hot water storage tank (22) for storing hot water boiled by a heat pump device;
Control means (12, 23) for controlling the heating operation of the heat pump device,
The control means starts the boiling operation at an initial predetermined time in the midnight power time zone and stops the boiling operation at a time before the end time of the midnight power time zone ,
When the boiling operation that starts at a predetermined time in the early hours of the midnight power hours is the first boiling operation,
The control means stops the first boiling operation at a time within the first half of the midnight power time zone, and after the first boiling operation is stopped, the remaining time in the midnight power time zone continues the first boiling operation. When the time is shorter than the time and when a predetermined condition is satisfied, the second boiling operation is started, and at least the second boiling operation is stopped at a predetermined time at the end of the late-night power period. Yes.

  Here, the initial period of the midnight power time zone means a time just before the start of the midnight power time zone, for example, a time within 2 hours from the start time of the midnight power time zone.

  According to this, when performing the boiling operation in the midnight power time zone, the boiling operation is performed in the time zone on the start time side where the outside air temperature is higher than the time zone on the end time side in the midnight power time zone. Compared with the case where the boiling operation is performed in the time zone on the end time side in the midnight power time zone, the boiling operation with higher operation efficiency is possible.

  In addition, since the boiling operation is performed during the midnight power hours, the user can use the hot water in the hot water storage tank without adjusting the temperature during the midnight power hours during the start time. In this case, the user can use hot water immediately after boiling. For this reason, according to this invention, the usability | use_condition of the user who uses hot water in the midnight electric power time zone can be improved.

  When the user uses the hot water in the hot water storage tank as it is without adjusting the temperature, for example, the hot water in the hot water storage tank and the hot water in the bath are heat-exchanged as described in claim 2 to The case where the hot water of the bath is reheated using the heat exchanger (51) for heating the water is mentioned.

  In addition, the code | symbol in the bracket | parenthesis of each means described in this column and the claim is an example which shows a corresponding relationship with the specific means as described in embodiment mentioned later.

It is a figure which shows the whole structure of the heat pump type water heater in 1st Embodiment. It is a figure which shows the structure of the hot water storage unit in FIG. It is a flowchart of the boiling operation control for the midnight electric power time slot | zone in 1st Embodiment. It is a figure which shows the implementation time of the boiling operation in 1st Embodiment and Comparative Example 1. FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, parts that are the same or equivalent to each other will be described with the same reference numerals.

(First embodiment)
As shown in FIG. 1, the heat pump type water heater 1 of this embodiment includes a heat pump unit 10 and a hot water storage unit 20.

  The heat pump unit 10 is a heat pump device that operates with electric power and boils hot water. The heat pump unit 10 has a refrigeration cycle functional component such as an electric compressor (not shown), a water refrigerant heat exchanger, a pressure reducing device (expansion valve), an evaporator (air refrigerant heat exchanger), etc., and a heat pump unit control. The device 12 is accommodated. The electric compressor, the water-refrigerant heat exchanger, the pressure reducing device, and the evaporator are sequentially connected by a refrigerant pipe, and constitute a refrigeration cycle (heat pump cycle).

  The water refrigerant heat exchanger of the heat pump unit 10 and the hot water storage tank 22 of the hot water storage unit 20 are connected by heat pump pipes 31 and 32. A circulation pump (not shown) that circulates hot water between the water-refrigerant heat exchanger and the hot water storage tank 22 is installed in the heat pump unit 10. The circulation pump may be installed in the hot water storage unit 20.

  The hot water storage unit 20 stores the hot water boiled by the heat pump unit 10.

  The hot water storage unit 20 includes a hot water storage tank 22 for storing hot water and a hot water storage unit control device 23 in a housing 21. The hot water storage tank 22 has a heat insulating structure made of foamed polystyrene or a vacuum heat insulating material, and has a structure in which a heat loss from the inside of the hot water storage tank 22 to the outside is suppressed.

  The hot water storage unit 20 is connected to a bath 41 through bath pipes 33 and 34, and is connected to a hot water supply terminal 42 such as a shower and a faucet through a water supply pipe 35 and a hot water supply pipe 36. The terminal 42 has a function of supplying hot water in the hot water storage tank 22.

  As shown in FIG. 2, in the hot water storage unit 20, the water supplied from the lower part of the hot water storage tank 22 is heated by the heat pump unit 10 during the boiling operation (during hot water storage), and the heated hot water is transferred to the upper part of the hot water storage tank 22. return.

  The hot water storage unit 20 mixes the hot water in the hot water storage tank 22 and the water sent from the water supply pipe at the hot water supply operation (at the time of hot water supply) by the hot water supply mixing valve 43 and adjusts it to the set temperature. Take a bath. In the hot water storage unit 20, the hot water in the hot water storage tank 22 and the water sent from the water supply pipe are mixed by the bath mixing valve 44 during the bath hot water operation (at the time of hot water supply) and adjusted so as to reach the set temperature. , Hot water in the bath 41. In the example of FIG. 2, it is possible to mix and use both hot and medium hot water in the hot water storage tank 22 by the mixing valve 45 during hot water supply, or to use either one. Yes.

  Further, the hot water storage unit 20 includes an additional cooking heat exchanger 51, additional cooking pipes 52 and 53 that connect the additional cooking heat exchanger 51 and the bath 41, and a non-illustrated additional cooking circulation pump. Thus, a reheating circuit 50 that circulates hot water between the bath 41 and the reheating heat exchanger 51 is configured.

  The additional cooking heat exchanger 51 heats the hot water in the bath 41 by exchanging heat between the hot water in the hot water storage tank 22 and the hot water in the bath 41. In the present embodiment, the additional cooking heat exchanger 51 is provided above the hot water storage tank 22. During the additional cooking operation, hot water circulates between the bath 41 and the additional heat exchanger 51 by the additional circulation pump, and the hot water in the bath 41 is heated by the additional heat exchanger 51. The hot water of the bath 41 is reheated. Here, additional cooking refers to a function of raising the hot water temperature of the water or hot water stored in the bath 41 without changing the amount of hot water.

  The hot water storage unit control device 23 controls the operation of each device, and performs a boiling operation, a hot water supply operation, and a hot water bath operation. The hot water storage unit controller 23 is supplied with operation signals from a remote controller and sensor signals from a plurality of temperature sensors 24 provided in the hot water storage tank 22.

  The hot water storage unit control device 23 outputs an instruction signal for the boiling operation to the heat pump unit control device 12 during the boiling operation. The heat pump unit control device 12 operates a compressor, a circulation pump, and the like in accordance with the boiling operation instruction. In the present embodiment, the hot water storage unit control device 23 and the heat pump unit control device 12 constitute a control means for controlling the heating operation of the heat pump device. In the present embodiment, the hot water storage unit control device 23 and the heat pump unit control device 12 are configured as separate control devices, but they may be configured as one control device.

  The hot water storage unit control device 23 performs normal boiling operation control for performing a boiling operation when the hot water in the hot water storage tank 22 runs short regardless of the time zone, and for performing a boiling operation during a midnight power time zone. The boiling operation control for the late-night power hours is executed.

  Incidentally, the midnight power time zone in this specification is a time zone from midnight to early morning when the electricity rate is cheaper than other time zones determined by a contract with a power company, for example, from 23:00 to early morning. Until 7 o'clock. In this midnight power time zone, the outside air temperature decreases as the time advances from the start time to the end time. For this reason, the outside air temperature is high in the time zone on the start time side in the midnight power time zone, and the outside air temperature is low in the time zone on the end time side in the midnight power time zone.

  Hereinafter, the boiling operation control for the midnight power time zone will be described with reference to the flowchart of FIG. Each step shown in FIG. 3 corresponds to means for executing various processes.

  The boiling operation control shown in FIG. 3 can be selected by the user using a remote controller. Therefore, the boiling operation control shown in FIG. 3 is performed when the hot water storage unit control device 23 and the heat pump unit control device 12 are supplied with power and the user has selected to perform this control. Incidentally, when the user has selected not to execute this control, the conventional boiling-up operation control described in the section of the background art is performed.

  In step S1, based on the timer which hot water storage unit control apparatus 23 has, it is determined whether the present time became the preset boiling start time. Specifically, it is determined whether or not the current time is the start time (23:00) of the midnight power time zone.

  In step S1, if the current time is before the start time of the midnight power time zone, a NO determination is made and step S1 is performed again. On the other hand, if the current time is the start time of the midnight power time zone, a YES determination is made and the process proceeds to step S2.

  In step S2, it is determined whether or not the boiling operation is necessary. Specifically, it is determined whether or not the heat quantity Q of the hot water in the hot water storage tank 22 is equal to or less than the first specified value A1. The amount of heat Q is calculated based on the temperature of hot water in the hot water storage tank 22 detected by a plurality of temperature sensors 24 provided in the hot water storage tank 22.

  If the amount of heat Q exceeds the first specified value A1 in step S2, a NO determination is made and it is not necessary to perform the boiling operation, so the boiling operation control in FIG. 3 is terminated. Therefore, when the hot water boiled up on the previous day remains in the hot water storage tank 22, the boiling operation in the midnight power time zone is not performed. On the other hand, if the amount of heat Q is equal to or less than the first specified value A1, a YES determination is made, the process proceeds to step S3, and a boiling operation (first boiling operation) is started. Specifically, a heating operation instruction signal is output to the heat pump unit control device 12, and the heat pump unit control device 12 starts the heating operation of the heat pump unit 10.

  Subsequently, in step S4, it is determined whether or not the boiling operation should be stopped. Specifically, it is determined whether or not the heat quantity Q in the hot water storage tank 22 is equal to or greater than the second specified value A2. The amount of heat Q is calculated in the same manner as in step S2. As the second specified value A2, a preset value (fixed value) is used so as to cover the daily hot water consumption. Note that, even if the second specified value A2 is not a fixed value, the hot water storage unit control device 23 obtains an average daily use heat amount based on the past use heat data, and according to the obtained average use heat amount. The second specified value A2 may be changed.

  If the amount of heat Q is less than the second specified value A2 in step S4, a NO determination is made and step S4 is performed again. Thereby, step S4 is repeated until the necessary amount of heat is obtained. If the heat quantity Q is equal to or greater than the second specified value A2, a YES determination is made, the process proceeds to step S5, and the boiling operation is stopped. Specifically, a boiling operation stop instruction signal is output to the heat pump unit control device 12, and the heat pump unit control device 12 stops the operation of the heat pump unit 10.

  The heating capacity of the heat pump unit 10 of the present embodiment is such that when boiling water or hot water in the hot water storage tank 22 is started from the start time of the midnight power time zone, the heating performance starts from the end time of the midnight power time zone. The amount of heat in the hot water storage tank 22 can be set to the second specified value or more at the previous time (mainly within the first half of the midnight power time zone). Accordingly, in step S5, the boiling operation is stopped at a time before the end time of the midnight power time period.

  Thereafter, in steps S6 to S8, it is determined whether or not the boiling operation (second boiling operation) is required in the time zone on the end time side in the midnight power time zone.

  That is, in step S6, it is determined whether or not the remaining time of the midnight power time zone is less than a predetermined time (α time). This predetermined time is set in advance such that the duration of the second boiling operation is shorter than the duration of the first boiling operation that is performed in the time zone on the start time side of the midnight power time zone.

  For example, when the average operation time of the first boiling operation is 3 hours, the predetermined time is set to 1 hour so that the operation time of the second boiling operation is 1 hour. The hot water storage unit control device 23 may measure the operation time of the first boiling operation and automatically set the predetermined time so as to be shorter than the measurement time.

  If the remaining time in the midnight power time zone is not less than α hours in step S6, NO is determined, and step S6 is repeated. If the remaining time in the midnight power time zone is less than α hours, YES is determined, and step Proceed to S7.

  In step S7, as in step S4, it is determined whether or not the heat quantity Q in the hot water storage tank 22 is equal to or greater than the second specified value A2. At this time, if the amount of heat Q is equal to or greater than the second specified value A2, a YES determination is made, the process proceeds to step S9, the second boiling operation is stopped, and the control of FIG. If the heat quantity Q is less than the second specified value A2, a YES determination is made and the process proceeds to step S8.

  In step S8, it is determined whether or not the current time is the end time (7 o'clock) of the midnight power time period. At this time, if the current time is the end time of the midnight power time zone, the process proceeds to step S9, the second boiling operation is stopped, and the control of FIG. 3 is ended. If the current time is before the end time of the midnight power time zone, a NO determination is made, the process proceeds to step S10, the second boiling operation is performed, and then step S7 is performed.

  By executing steps S6 to S10, when the remaining time in the midnight power time period becomes less than α hours, the amount of heat Q in the hot water storage tank 22 is equal to or greater than the second specified value A2, that is, the first boiling After operation, when there is a sufficient amount of heat in the hot water storage tank 22, the second boiling operation is not performed, and when the heat amount Q in the hot water storage tank 22 is less than the second specified value A2, the second boiling operation is started. To do. Then, when the amount of heat Q in the hot water storage tank 22 is equal to or greater than the second specified value A2, or when the current time is the end time of the midnight power hours, the second boiling operation is stopped.

  Next, main features of the present embodiment will be described.

  As described above, in the present embodiment, the hot water storage unit control device 23 performs the steps S1, S2, and S3, so that the heat amount Q in the hot water storage tank 22 is reached when the start time of the midnight power time zone is reached. Is lower than the first specified value A1, the first boiling operation is started. Then, by executing step S4, the first boiling operation is stopped when the heat quantity Q in the hot water storage tank 22 becomes higher than the second specified value A2. Thus, the first boiling operation is stopped at a time before the end time of the midnight power time period.

  Therefore, as shown in FIG. 4, in the present embodiment, the first boiling operation is performed in the time zone on the start time side where the outside air temperature is higher than the time zone on the end time side in the midnight power time zone. Become. Therefore, according to the present embodiment, as compared to Comparative Example 1 in FIG. 4, it is compared with the case where the boiling operation is performed in the time zone on the end time side of the midnight power time zone (the second half of the midnight power time zone). Thus, boiling operation with high operation efficiency is possible. In addition, the comparative example 1 in FIG. 4 is the boiling-up operation control of the prior art demonstrated in the column of the said background art, and the boiling operation of a boiling operation is complete | finished so that a boiling operation may be complete | finished at the end time of a midnight electric power time slot | zone. The start time is determined.

  Further, when performing the boiling operation control of Comparative Example 1, as described in the column of the problem to be solved by the invention, if there is a heat amount equal to or greater than a predetermined amount in the hot water storage tank, the start time of the midnight power time zone During the time zone on the side, the boiling operation is not executed.

  However, even when hot water having a heat quantity equal to or greater than a predetermined value remains in the hot water storage tank, the hot water temperature in the hot water storage tank is lower than that immediately after boiling due to heat dissipation. For this reason, when a user uses the hot water in the hot water storage tank 22 as it is without adjusting the temperature in the time zone on the start time side in the midnight power time zone, there is a problem that the user's feeling of use is poor. Specifically, the hot water temperature of the hot water in the hot water storage tank 22 (high temperature part) is lower than immediately after boiling when the additional heat of the heat exchanger 51 for additional cooking is used to heat the bath 41. Because of this, the cooking time will be longer.

  On the other hand, in this embodiment, since the boiling operation is performed in the time zone on the start time side in the midnight power time zone, the additional cooking operation is performed in the time zone on the start time side in the midnight power time zone. At this time, it is possible to perform additional cooking of the bath 41 using hot hot water immediately after boiling in the hot water storage tank 22. For this reason, according to this embodiment, since the additional cooking time can be shortened compared with the case where the boiling-up control of the comparative example 1 is performed, the user is comfortable, that is, the hot water is used during the midnight power hours. User experience can be improved.

  In the present embodiment, the hot water storage unit control device 23 executes steps S6 to S10, so that the heat quantity Q in the hot water storage tank 22 is the second specified value in the time zone on the end time side in the midnight power time zone. When it is lower than A2, the boiling operation (second boiling operation) is performed again.

  Thereby, when the heat quantity Q in the hot water storage tank 22 decreases due to the heat dissipation of the hot water in the hot water storage tank 22 or the use of hot water in the midnight power hours, the reduced heat quantity can be supplemented.

  Moreover, the hot water storage unit control device 23 sets the start time of the second boiling operation so that the duration of the second boiling operation is shorter than the duration of the first boiling operation, as described in step S6. It is set. Thereby, the operation continuation time of the heating operation in the time zone on the end time side where the outside air temperature is low and the operation efficiency is low in the midnight power time zone is suppressed as short as possible.

(Other embodiments)
The present invention is not limited to the above-described embodiment, and can be appropriately modified within the scope described in the claims as follows.

  (1) In the first embodiment, it is determined in step S1 whether or not the start time of the midnight power time zone has been reached, but if it is a predetermined time at the beginning of the midnight power time zone, the start time of the midnight power time zone It may be a later time. The initial period of the midnight power time zone means a time just before the start of the midnight power time zone, for example, within 2 hours from the start time of the midnight power time zone (the total time of the midnight power time zone is 8 hours) In this case, the time is within a quarter of the total time. Since the outdoor air temperature has the highest start time in the midnight power time zone, it is preferable to start the boiling operation at a time as close as possible to the start time in the midnight power time zone.

  (2) In the first embodiment, when steps S1 and S2 are executed and the start time of the midnight power time zone comes, and when the amount of heat in the hot water storage tank 22 is lower than the first specified value A1 Although the first boiling operation is started, the first boiling operation may be started when the start time of the midnight power time zone is reached regardless of the amount of heat in the hot water storage tank 22.

  (3) In the first embodiment, in steps S2 and S4, the determination is made by comparing the quantity Q of hot water in the hot water storage tank 22 with a specified value such as the first specified value A1, but the plurality of temperature sensors 24 detect it. The determination may be made by comparing the hot water temperature in the hot water storage tank 22 with a specified value. In this case, for example, an average value of the hot water temperatures detected by the plurality of temperature sensors 24 is used.

  (4) In the first embodiment, as described in step S7, when the predetermined condition is satisfied, that is, when the heat quantity Q of the hot water in the hot water storage tank 22 is lower than the second specified value A2, the second boiling operation is performed. However, the second boiling operation may be started when other predetermined conditions are satisfied.

  For example, the hot water temperature in the hot water storage tank 22 detected by the plurality of temperature sensors 24 may be compared with a specified value, and the second boiling operation may be started when the hot water temperature is lower than the specified value.

  Further, the heat release amount of the hot water storage tank 22 can be calculated from the heat retention performance of the hot water storage tank 22 and the outside air temperature. Therefore, an outside air temperature sensor 25 as a detecting means for detecting the outside air temperature is provided in the heat pump unit 10, and calculation is performed based on the heat retention performance of the hot water storage tank 22 and the outside air temperature detected by the outside air temperature sensor 25 at step S7. It is determined whether or not the heat release amount of the hot water storage tank 22 exceeds a predetermined value, and if it exceeds, it is determined that the boiling operation needs to be performed and the second boiling operation is started. Also good. At this time, for example, an average value of the outside air temperature from the time when the first boiling operation is stopped to the time of step S7 is used as the outside air temperature.

  Moreover, since the heat retention performance of the hot water storage tank 22 is constant, the heat radiation amount of the hot water storage tank 22 varies depending on the outside air temperature. That is, the lower the outside air temperature, the greater the amount of heat released from the hot water storage tank 22. Therefore, it is possible to determine whether or not to perform the boiling operation only based on the outside air temperature from when the heating operation is stopped to the current time without calculating the heat release amount. Therefore, it is determined whether or not the outside air temperature detected by the outside air temperature sensor 25 is lower than the predetermined temperature. If the outside air temperature is lower than the predetermined temperature, it is determined that the second boiling operation needs to be performed, and the second boiling is performed. The raising operation may be started. At this time, for example, an average value of the outside air temperature from the time when the first boiling operation is stopped to the time of step S7 is used as the outside air temperature.

  (5) In the first embodiment, it is determined in step S8 whether or not the end time of the midnight power time zone has been reached, but if it is a predetermined time at the end of the midnight power time zone, the end time of the midnight power time zone It may be an earlier time. Note that the end of the midnight power time zone means the end time of the midnight power time zone, and is, for example, the time from the end time of the midnight power time zone to 2 hours before the end time.

  (6) The above embodiments are not irrelevant to each other and can be combined as appropriate unless the combination is clearly impossible. In each of the above-described embodiments, it is needless to say that elements constituting the embodiment are not necessarily indispensable except for the case where it is clearly indicated that the element is essential and the case where the element is clearly considered essential in principle. Yes.

1 Heat pump type water heater 10 Heat pump unit (heat pump device)
12 Heat pump unit control device (control means)
20 Hot water storage unit 22 Hot water storage tank 23 Hot water storage unit control device (control means)
51 Heat exchanger for additional cooking

Claims (7)

A heat pump device (10) operated by electric power and boiling water,
A hot water storage tank (22) for storing hot water boiled by the heat pump device;
Control means (12, 23) for controlling the heating operation of the heat pump device,
Wherein, in the initial predetermined time midnight power time zone, starts the heating operation, the time before the end time of the midnight power time zone, the boiling-up stop operation,
When the boiling operation starting at a predetermined time in the early hours of the midnight power time period is the first boiling operation,
The control means stops the first boiling operation at a time within the first half of the midnight power time zone, and after stopping the first boiling operation, the remaining time of the midnight power time zone is When the duration of the 1-boiling operation is shorter and when a predetermined condition is satisfied, the second boiling operation is started, and at least at the predetermined time at the end of the late-night power period, the second boiling-up operation is started. A heat pump type water heater characterized by stopping the operation.   The heat pump type water heater according to claim 1, further comprising a heat exchanger (51) that heat-exchanges the hot water in the hot water storage tank and the hot water in the bath to heat the hot water in the bath.   3. The heat pump hot water heater according to claim 1, wherein an initial predetermined time in the midnight power time zone is a start time of the midnight power time zone. Said control means, in a case where became initial predetermined time of the midnight power time zone, further wherein when the hot water temperature or heat of the hot water storage tank is lower than the prescribed value, the first water heating operation The heat pump type hot water heater according to any one of claims 1 to 3, wherein the heat pump type hot water heater is started. Wherein when the predetermined condition is satisfied, the heat pump water heater according to any one of claims 1 to 4, wherein the heat or temperature of the hot water of the hot water storage tank is lower than a specified value . A detecting means (25) for detecting the outside air temperature;
The case where the predetermined condition is satisfied is a case where the heat dissipation amount of the hot water storage tank calculated based on the outside air temperature detected by the detecting means is larger than a predetermined amount . The heat pump type water heater according to one . A detecting means (25) for detecting the outside air temperature;
The case where the predetermined condition is satisfied is a case where the outside air temperature detected by the detection means is lower than a predetermined temperature, and the heat pump type hot water heater according to any one of claims 1 to 4 .

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