JP4218212B2 - Water heater - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a heat pump type hot water supply apparatus.
[0002]
[Prior art]
Conventionally, a refrigerant compressor, a refrigerant flow path of a water refrigerant heat exchanger, an expansion valve, and a heat pump cycle in which an air heat exchanger provided with an outdoor fan is annularly connected by a refrigerant pipe, and a tank for storing hot water, The tank and the hot water flow path of the water refrigerant heat exchanger are connected by a hot water supply pipe, a hot water circuit in which a circulation pump is interposed in the hot water supply pipe, and a controller that controls the circulation pump, the expansion valve, and the refrigerant compressor There is known a hot water supply device equipped with
[0003]
[Problems to be solved by the invention]
The conventional hot water supply apparatus has the following problems.
The refrigerant compressor, the expansion valve, the heat pump cycle, and the circulation pump may fail due to lightning strikes or reaching the endurance time (examples are shown below).
If the operation of the hot water supply device is continued in the state of failure, not only hot water of a predetermined temperature cannot be supplied to the tank, but also the equipment may be damaged.
[0004]
[Circulation pump failure, clogged hot water flow path of water refrigerant heat exchanger]
Since the heat pump cycle is normal, high-temperature and high-pressure refrigerant is discharged from the refrigerant compressor and supplied to the water refrigerant heat exchanger. However, since the water present in the hot water flow path of the water refrigerant heat exchanger does not circulate, it gradually becomes hot due to the high-temperature refrigerant supplied from the refrigerant flow path, and when the temperature of the hot water exceeds a predetermined temperature and further time passes, it boils. End up.
[0005]
[When expansion valve is closed and broken]
When it is completely closed, the refrigerant pressure in the heat pump cycle becomes an ultra-high pressure by the refrigerant discharged from the refrigerant compressor.
[0006]
If it does not move at a position in the middle of the closing side, if it is operated at the rotation speed of the refrigerant compressor within the normal range, even if the flow rate of the circulation pump is maximized, the hot water supply temperature exceeds the target hot water supply temperature.
Alternatively, (exit side refrigerant temperature of refrigerant channel−inlet side hot water temperature of hot water channel)> target temperature difference.
Alternatively, the refrigerant pressure in the heat pump cycle becomes abnormally high due to the refrigerant discharged from the refrigerant compressor.
[0007]
[When the expansion valve is broken on the open side]
When fully open, the refrigerant pressure in the heat pump cycle does not reach a predetermined high pressure, and even if the flow rate of the circulation pump is minimized, the temperature of the hot water supplied to the tank does not reach a predetermined temperature.
[0008]
[When the refrigerant compressor is broken]
Since high-temperature and high-pressure refrigerant is not discharged from the refrigerant compressor, the temperature of the hot water supplied to the tank is kept low.
[0009]
[When the outdoor fan has failed]
Since the air heat exchanger does not absorb heat from the outside air, the refrigerant passes through the air heat exchanger in a high temperature state.
[0010]
  The present inventionEyesIn the case of failure, the operation automatically stops.WithAn object of the present invention is to provide a hot water supply device that can identify a failure location.
[0015]
[Means for Solving the Problems]
  [Claims1about〕
  The hot water supply device has a heat pump cycle in which a refrigerant compressor, a refrigerant flow path of a water-refrigerant heat exchanger, an expansion valve, and an air heat exchanger are connected in an annular shape with a refrigerant pipe, and a tank for storing hot water. Connect the hot water flow path of the refrigerant heat exchanger with a hot water supply pipe, a hot water circuit with a circulation pump in the hot water supply pipe, and a circulating pump, expansion so that the temperature of the hot water to be supplied to the tank reaches a predetermined temperature. And a controller that controls energization of the refrigerant compressor within a predetermined control range.
[0016]
And even if the controller controls the circulation pump, the expansion valve, and the refrigerant compressor to the limit of each predetermined control range, the temperature of the hot water to be supplied to the tank is predetermined before the predetermined time elapses after the apparatus is started. If the temperature is not reached, it is determined that the heat pump cycle has failed.
[0017]
Thereby, when a heat pump cycle fails, since it can determine with a failure location being a heat pump cycle, it is excellent in maintainability.
[0018]
  [Claims2about〕
  The hot water supply device has a heat pump cycle in which a refrigerant compressor, a refrigerant flow path of a water-refrigerant heat exchanger, an expansion valve, and an air heat exchanger are connected in an annular shape with a refrigerant pipe, and a tank for storing hot water. Connect the hot water flow path of the refrigerant heat exchanger with a hot water supply pipe, a hot water circuit with a circulation pump in the hot water supply pipe, and a circulating pump, expansion so that the temperature of the hot water to be supplied to the tank reaches a predetermined temperature. And a controller that controls energization of the refrigerant compressor within a predetermined control range.
[0019]
When the temperature of the hot water supplied to the tank does not reach the specified temperature, the controller attempts to increase the temperature of the hot water by lowering the flow rate of the circulation pump, and when the pump flow rate reaches the lower limit of the control range, the opening of the expansion valve Is controlled in the direction of closing the hot water temperature, and when the opening degree of the expansion valve reaches the lower limit opening degree, the temperature of the refrigerant compressor is controlled to increase so that the hot water temperature is increased. Even if the capacity of the refrigerant compressor reaches the upper limit of the control range, if the temperature of the hot water supplied to the tank does not reach a predetermined temperature and the refrigerant discharge temperature is low, a heat pump cycle failure including an expansion valve open failure may occur. The controller determines that it has occurred.
As a result, when a heat pump cycle failure including an expansion valve open failure occurs, it can be determined that the heat pump cycle failure includes an expansion valve open failure, so that maintainability is excellent.
[0020]
  [Claims3about〕
  The hot water supply device has a heat pump cycle in which an air heat exchanger provided with a refrigerant compressor, a refrigerant flow path of a water refrigerant heat exchanger, an expansion valve, and an outdoor fan is connected in an annular shape with a refrigerant pipe, and a tank for storing hot water The tank and the hot water flow path of the water-refrigerant heat exchanger are connected by a hot water supply pipe, a hot water circuit in which a circulation pump is interposed in the hot water supply pipe, and the temperature of the hot water to be supplied to the tank become a predetermined temperature. , A circulation pump, an expansion valve, an outdoor fan, and a controller that controls energization of the refrigerant compressor within predetermined control ranges.
[0021]
Even if the controller controls the circulation pump, the expansion valve, the outdoor fan, and the refrigerant compressor to the limit of each predetermined control range until the predetermined time elapses after the device is started, the temperature of the hot water rises. If the refrigerant discharge temperature does not rise, it is determined that the refrigerant compressor or its drive circuit has failed.
[0022]
Thereby, when the refrigerant compressor or its drive circuit breaks down, it can be reliably determined that the cause of the failure is the refrigerant compressor or its drive circuit.
[0027]
DETAILED DESCRIPTION OF THE INVENTION
  First of the present inventionReference examplesThis will be described with reference to FIGS. The hot water supply apparatus A includes a compressor 1, a refrigerant flow path 21 of a water / refrigerant heat exchanger 2, an expansion valve 3, an air heat exchanger 4 provided with an outdoor fan 41, and an accumulator (not shown) in an annular shape by a refrigerant pipe 42. A hot water circuit W in which a connected heat pump cycle H, a hot water storage tank 5 for storing hot water for hot water supply, and a hot water passage 22 of the water-refrigerant heat exchanger 2 are connected by a hot water pipe 51 and a circulation pump 6 is provided in the middle. And a controller (not shown).
[0028]
The compressor 1 is driven by a built-in electric motor, and compresses and discharges the gas-phase refrigerant sucked from the accumulator to a critical pressure or higher. Note that the capacity (rotational speed) of the compressor 1 increases or decreases in accordance with the amount of power supplied to the electric motor.
[0029]
The water-refrigerant heat exchanger 2 has a refrigerant channel 21 through which refrigerant (carbon dioxide) discharged from the compressor 1 flows, and a hot water channel 22 through which hot water flows.
The refrigerant (hot gas) compressed to high temperature and high pressure by the compressor 1 described above flows in the refrigerant flow path 21 of the water refrigerant heat exchanger 2, and thereby reversely flows in the hot water flow path 22 of the water refrigerant heat exchanger 2. The hot water flowing in is heated and the hot water temperature rises.
A hot water temperature sensor 511 and a hot water temperature sensor 512 (boiling temperature sensor) are disposed on the inlet and outlet sides of the hot water flow path 22, respectively, and refrigerant is provided on the outlet side and inlet side of the refrigerant flow path 21, respectively. A temperature sensor 421 and a refrigerant discharge temperature sensor 422 are arranged.
[0030]
The expansion valve 3 has a valve body that is driven by an actuator, and can vary the valve opening according to the amount of current supplied to the actuator. When the refrigerant passes through the expansion valve 3, it expands to a low pressure.
[0031]
The air heat exchanger 4 evaporates the low-temperature refrigerant that has been decompressed through the expansion valve 3 by exchanging heat with the outside air blown by the outdoor fan 41 (atmospheric heat absorption). An accumulator is provided for gas-liquid separation of the refrigerant flowing out of the air heat exchanger 4, and the gas-phase refrigerant is sent to the compressor 1. In addition, the refrigerant | coolant input temperature sensor 411, the frost temperature sensor 412, and the external temperature sensor 413 are each arrange | positioned at the inlet of the air heat exchanger 4, the exit side, and fan vicinity.
[0032]
The hot water pipe 51 is a pipe that connects a hot water outlet 52 provided in the lower part of the hot water storage tank 5 and a hot water inlet 53 provided in the upper part.
Hot water in the hot water storage tank 5 is discharged from the hot water outlet 52 by the circulation pump 6 and passes through the hot water pipe 51 through the hot water passage 22 of the water / refrigerant heat exchanger 2, and the heated hot water is supplied from the hot water inlet 53 to the hot water storage tank 5. Return inside.
[0033]
Based on the outputs of the water supply temperature sensor 511, the hot water supply temperature sensor 512, the refrigerant temperature sensor 421, the refrigerant discharge temperature sensor 422, the refrigerant input temperature sensor 411, the frost temperature sensor 412, and the outside air temperature sensor 413, the hot water storage tank The energization of the circulation pump 6, the expansion valve 3, the outdoor fan 41, and the electric motor of the compressor 1 is controlled within each safe control range so that the temperature of the hot water supplied to the hot water 5 becomes the target hot water temperature.
[0034]
Next, the control of the controller of the hot water supply apparatus A will be described based on the flowcharts shown in FIGS.
[Overall control; Fig. 2]
In step s1, each control variable and timer are initialized.
In step s2, input processing of each output sent by the feed water temperature sensor 511, the hot water supply temperature sensor 512, the refrigerant temperature sensor 421, the refrigerant discharge temperature sensor 422, the refrigerant input temperature sensor 411, the frost temperature sensor 412 and the outside air temperature sensor 413 is performed. Do. Moreover, the input process of the actual rotation speed of the compressor 1 is also performed.
[0035]
In step s3, it is determined whether or not boiling is performed. If boiling is performed (YES), the process proceeds to step s9. If boiling is not performed (NO), the process proceeds to step s4. The determination of boiling is performed based on a manual operation from the operation panel or a boiling control program stored in the microcomputer of the controller.
In step s9, the operations of the circulation pump 6, the outdoor fan 41, and the compressor 1 are all stopped.
[0036]
In step s4, the calculation shown in the flowchart of FIG.
In step s5, the circulation pump control shown in the flowchart of FIG. 5 is performed to calculate and obtain the target flow rate of the circulation pump 6, and the output to be the target flow rate is determined.
[0037]
In step s6, the outdoor fan 41 is calculated to determine an output at which the rotational speed of the outdoor fan 41 becomes a predetermined rotational speed.
However, the output is determined so that the rotational speed is higher than the predetermined rotational speed in order to increase the heat exchange efficiency under severe conditions (refrigerant discharge temperature Tco> 140 ° C.) with respect to the refrigerant load. As a result, the discharge refrigerant pressure and the discharge refrigerant temperature from the compressor 1 are both guided in a decreasing direction.
[0038]
In step s7, calculation relating to control of the compressor 1 is performed.
The output is determined so that the number of revolutions increases as the outside air temperature Tam decreases, and the output is determined such that the number of revolutions decreases as the outside air temperature Tam increases. Further, when the hot water supply temperature two does not reach the target hot water supply temperature Tp, the output is determined so as to increase the rotation speed, and when the hot water supply temperature two is too high, the output is determined so as to decrease the rotation speed.
[0039]
In step s8, the expansion valve 3, the circulation pump 6, the outdoor fan 41, and the compressor 1 are controlled with each output.
[0040]
[Expansion valve control; Fig. 3]
In step s41, it is determined whether or not the elapsed time from the start is within a predetermined time (1 minute). If it is within the predetermined time, the process proceeds to step s42. If the predetermined time is exceeded, the process proceeds to step s43.
[0041]
If the elapsed time is within the predetermined time, the heat pump cycle H and the hot water circuit W are in a transient state, so in step s42, the initial opening before starting to increase the load (the opening of the expansion valve is EV = 300). Fix to stabilize the cycle.
[0042]
When the elapsed time exceeds a predetermined time, a target temperature ΔT at which the heat pump cycle H operates efficiently is determined. Target temperature ΔT = refrigerant outlet temperature Tro−feed water temperature Twi, and the opening degree EV of the expansion valve is determined so that the target temperature ΔT is about 10 ° C.
[0043]
In step s44, it is determined whether or not the target temperature ΔT <9 ° C., and if the target temperature ΔT <9 ° C. (YES), the process proceeds to step s45, and if the target temperature ΔT ≧ 9 ° C. (NO). Advances to step s46.
In step s45, the expansion valve 3 is controlled to open in order to improve efficiency.
In step s46, it is determined whether or not the target temperature ΔT> 11 ° C., and if the target temperature ΔT> 11 ° C. (YES), the process proceeds to step s47, and if the target temperature ΔT ≦ 11 ° C. (NO). Advances to step s48.
[0044]
In step s47, the expansion valve 3 is controlled in the closing direction so that the efficiency is improved. If the valve opening degree of the expansion valve 3 is determined, abnormality determination of the expansion valve 3 shown in FIG. 4 is performed in step s48.
[0045]
[Expansion valve abnormality determination; FIG. 4]
In step s481, it is determined whether or not the discharge-side refrigerant pressure> the predetermined pressure based on the output of the refrigerant discharge temperature sensor 422. If the discharge-side refrigerant pressure> the predetermined pressure (YES), the process proceeds to step s483, and the discharge If the side refrigerant pressure ≦ the predetermined pressure (NO), the process proceeds to step s482.
[0046]
In step s482, it is determined that the heat pump cycle H is normal, and the process proceeds to step s5 in FIG. In step s483, the operations of the circulation pump 6, the outdoor fan 41, and the compressor 1 are all temporarily stopped.
[0047]
In step s484, the pre-failure flag is turned ON and stored so that the cause of the failure can be understood later. Then, it is estimated that the refrigerant of the heat pump cycle H is not circulating or the expansion valve 3 is closed.
[0048]
In step s485, it is determined whether or not the retry counter> 3 times. If the retry counter ≦ 3 times (NO), the process proceeds to step s486, and if the retry counter> 3 times (YES), the step is repeated. Proceed to s487.
[0049]
In step s486, settings for retry are performed. Set boiling from stop to restart and increment the retry counter by one. Then, it progresses to step s5 of FIG.
In step s486, settings for retry are performed. Set boiling from stop to restart and increment the retry counter by one.
In step s487, since the discharge side refrigerant pressure> predetermined pressure state is not improved even after restarting four times or more, it is determined that the heat pump cycle H has failed, including the closing failure of the expansion valve 3. Then, it progresses to step s5 of FIG.
[0050]
[Circulating pump control; Fig. 5]
In step s51, it is determined whether or not the elapsed time from the start is within a predetermined time (1 minute). If it is within the predetermined time, the process proceeds to step s52, and if it exceeds the predetermined time (1 minute), the process proceeds to step s53. Proceed to
[0051]
If the elapsed time is within the predetermined time, the heat pump cycle H and the hot water circuit W are in a transient state, and in step s52, the hot water supply temperature is set to a flow rate before starting to rise (NpD = 80%), and the cycle is stabilized.
[0052]
When the elapsed time exceeds the predetermined time, a difference ΔdT between the hot water supply target value Tp and the actual hot water supply temperature Two is obtained from the following equation.
ΔdT = Tp−Two
[0053]
Whether ΔdT ≧ 2 ° C. is determined in step s54. If ΔdT ≧ 2 ° C. (boiling not achieved; YES), the process proceeds to step s55. In step s55, the flow rate NpD is decreased by Knpd so as to reach the target hot water supply temperature Tp.
[0054]
Whether or not ΔdT ≦ −2 ° C. is determined in step s56. If ΔdT ≦ −2 ° C. (too much boiling; YES), the process proceeds to step s57. In step s57, the flow rate NpD is increased by Knpd so as to reach the target hot water supply temperature Tp.
If the flow rate is determined, in step s58, abnormality determination of the circulation pump shown in FIG. 6 is performed, and the process proceeds to step s6 in FIG.
In step s57, the flow rate NpD is increased by Knpd so as to reach the target hot water supply temperature Tp.
[0055]
[Circulating pump abnormality determination; FIG. 6]
In step s581, it is determined whether or not the elapsed time from the start is within a predetermined time (1 minute). If within the predetermined time (YES), the process proceeds to step s582 and exceeds the predetermined time (1 minute). (NO) advances to step s583.
[0056]
In step s582, it is determined that the heat pump cycle H is normal, and the process proceeds to step s6 in FIG.
In step s583, it is determined whether or not the hot water supply temperature Two is a boiling temperature.
If Two <97 ° C., the process proceeds to step s584 because it has not reached the boiling temperature, and if Two ≧ 97 ° C., the process proceeds to step s585, assuming that the boiling temperature has been reached.
[0057]
In step s584, it is determined that the hot water circuit W is normal, and then the process proceeds to step s6 in FIG. In step s585, the operations of the circulation pump 6, the outdoor fan 41, and the compressor 1 are all temporarily stopped.
[0058]
In step s586, the pre-failure flag is turned ON and stored so that the cause of the failure can be understood later. And it estimates that the refrigerant | coolant of the heat pump cycle H is not circulating, or the circulation pump 6 has failed.
[0059]
In step s587, it is determined whether or not retry counter> 3 times. If retry counter ≦ 3 times (NO), the process proceeds to step s588, and if retry counter> 3 times (YES), step is reached. Proceed to s589.
[0060]
In step s588, settings for retry are performed. Set boiling from stop to restart and increment the retry counter by one. Then, it progresses to step s6 of FIG.
In step s589, since stop control is applied even after restarting four times or more, it is determined that the hot water circuit W is faulty (the circulation pump 6 is faulty and the hot water pipe 51 is clogged). Then, it progresses to step s6 of FIG.
[0061]
  BookreferenceThe example hot water supply apparatus A has the following advantages. In the hot water supply apparatus A, when the refrigerant discharge temperature sensor 422 that detects an abnormality in the refrigerant pressure on the discharge side of the compressor 1 detects a pressure exceeding a predetermined pressure (YES in step s481), or when the hot water supply temperature has reached the boiling temperature (YES in step s583) is a configuration in which the controller temporarily stops the operations of the circulation pump 6, the outdoor fan 41, and the compressor 1 (steps s483 and s585).
[0062]
In addition, when the engine is stopped four times or more for the same reason even after restarting, the heat pump cycle H or the hot water circuit W is faulty (the expansion valve 3 is closed, the circulation pump 6 is faulty, the hot water pipe 51 is The hot water supply apparatus A has a failure diagnosis function for determining that it is clogged). For this reason, the hot water supply apparatus A is excellent in safety and maintenance.
[0063]
  Next, the first of the present invention1ImplementationExample1, FIG. 2, FIG. 3, and FIG. The mechanical configuration of the hot water supply apparatus B is the same as that of the hot water supply apparatus A, and the control of the controller shown below is different.
[0064]
The hot water supply apparatus B is controlled by a controller based on the flowcharts shown in FIGS. 2, 3, and 7. The process proceeds from step s4 in FIG. 2 to step s41 in FIG. 3, and further proceeds from step s48 in FIG. 3 to step s488 in FIG. 7 to determine whether the expansion valve 3 is abnormal.
[0065]
[Expansion valve abnormality determination; FIG. 7]
In step s488, it is determined whether or not the elapsed time from the start is within a predetermined time (1 minute). If it is within the predetermined time (YES), the process proceeds to step s489, and if the predetermined time is exceeded (NO) Proceed to step s490.
[0066]
In step s489, it is determined that the heat pump cycle H is normal, and the process proceeds to step s5 in FIG. In step s490, it is determined whether or not the target hot water supply temperature> the hot water supply temperature Two + the allowable temperature difference Ktwo and the allowable temperature is exceeded. If the temperature is within the allowable temperature (NO), the process proceeds to step s489.
[0067]
In step s491, it is determined whether or not the flow rate NpD of the circulation pump 6 is the lowest. If NpD is the lowest (YES), the process proceeds to step s493. If NpD is not the lowest (NO), the process proceeds to step s492. move on.
[0068]
In step s492, in order to raise the hot water supply temperature, the flow rate NpD of the circulation pump 6 is decreased by Knpd, and the process proceeds to step s5 in FIG.
[0069]
In step s493, it is determined whether or not the opening degree of the expansion valve 3 is the minimum. If the opening degree is not the minimum (NO), the process proceeds to step s494. If the opening degree is the minimum (YES), the step is performed. Proceed to s495. In step s494, the expansion valve 3 is controlled in the closing direction (up to the lower limit) to increase the refrigerant discharge pressure and discharge temperature, thereby raising the hot water supply temperature. Then, the process proceeds to step s5 in FIG.
[0070]
In step s495, in order to raise the hot water supply temperature, the rotation speed of the compressor 1 is increased, and the flow proceeds to step s496. In step s496, it is determined whether or not the refrigerant discharge temperature Tco is low. If the refrigerant discharge temperature Tco is high (NO), the process proceeds to step s5 in FIG. 2, and if the refrigerant discharge temperature Tco is low (YES), step s497 is performed. Proceed to
[0071]
In step s497, it is determined that the heat pump cycle H has failed (refrigerant leakage or expansion valve 3 is open), and the process proceeds to step s5 in FIG.
[0072]
The hot water supply apparatus B of the present embodiment has the following advantages.
The controller of the hot water supply device B is activated when the temperature of the hot water supplied to the hot water storage tank 5 is equal to the target hot water supply temperature Tp> the hot water supply temperature Two + the allowable temperature difference K2wo (YES in step s490) even if it exceeds 1 minute after starting. Attempts to increase the temperature of the hot water by lowering the capacity of the circulation pump 6 (step s491). When the pump capacity reaches the lower limit of the control range (YES in step s491), the opening of the expansion valve 3 is then closed. If the opening degree of the expansion valve 3 reaches the lower limit opening degree (YES in step s493), the hot water temperature is controlled to increase the capacity of the compressor 1 when the opening degree of the expansion valve 3 reaches the lower limit opening degree (YES in step s493). (Step s495).
Thereby, the hot water supply capability can be increased to the maximum, and hot water at the target hot water supply temperature can be supplied to the hot water storage tank 5.
[0073]
If the temperature of the hot water supplied to the hot water storage tank 5 does not reach the predetermined temperature even when the capacity of the compressor 1 reaches the upper limit of the control range and the refrigerant discharge temperature is low (YES in step s496), the expansion valve is opened. In this configuration, it is determined that a heat pump cycle failure including a failure has occurred (step s497).
[0074]
Thereby, when the heat pump cycle H is out of order (refrigerant leakage or expansion valve 3 is open), it is reliably determined that the heat pump cycle H is out of order, so that the maintainability is excellent.
[0075]
  Next, the first of the present invention2ImplementationExampleThis will be described with reference to FIGS. 1, 2, and 8. The mechanical configuration of the hot water supply apparatus C is the same as that of the hot water supply apparatus A, and the control of the controller shown below is different.
[0076]
The hot water supply apparatus C is controlled by a controller based on the flowcharts shown in FIGS. 2, 3, and 8.
[Compressor control & abnormality determination; Fig. 8]
The process proceeds from step s7 in FIG. 2 to step s71 in FIG.
[0077]
[Compressor abnormality determination; Fig. 8]
In step s71, it is determined whether or not the elapsed time from the start is within a predetermined time (1 minute). If the predetermined time is within the predetermined time (YES), the process proceeds to step s72. Proceed to step s73.
[0078]
If the target hot water supply temperature Tp> the hot water supply temperature Two + the allowable temperature difference Ktwo in step s73 (YES), it is determined that the hot water supply capacity is insufficient, and the process proceeds to step s74, where the difference between the target hot water supply temperature Tp and the hot water supply temperature Two is allowable. If it is within the temperature (NO), the process proceeds to step s72.
[0079]
In step s72, it is determined that the heat pump cycle H is normal, and the process proceeds to step s8 in FIG.
In step s74, it is determined whether the hot water supply temperature Two and the refrigerant discharge temperature Tco are not increased at all. If they are increased (NO), the process proceeds to step s8 in FIG.
In step s75, it is determined that the compressor 1 or the inverter that drives the compressor 1 has failed. Thereafter, the process proceeds to step s8 in FIG.
[0080]
The hot water supply apparatus C of the present embodiment has the following advantages.
The controller of the hot water supply apparatus C is activated when the temperature of the hot water to be supplied to the hot water storage tank 5 is equal to the target hot water supply temperature Tp> the hot water supply temperature Two + the allowable temperature difference Ktwo even after 1 minute has been started (YES in step s73). Determines whether the hot water supply temperature Two and the refrigerant discharge temperature Tco do not rise at all (step s74), and if not (YES in step s74), the compressor 1 or the inverter that drives the compressor 1 fails. It is the structure determined to be.
[0081]
Thereby, when the compressor 1 and the inverter are out of order, it is reliably determined that the compressor 1 and the inverter are out of order, so the hot water supply device C is excellent in maintainability.
[0082]
  Next, the first of the present invention3ImplementationExampleThis will be described with reference to FIGS. 1, 2, and 9. The mechanical configuration of the hot water supply apparatus D is the same as that of the hot water supply apparatus A, and the control of the controller shown below is different.
[0083]
The hot water supply device D is controlled by a controller based on the flowcharts shown in FIGS.
[Fan control & abnormality determination; Fig. 9]
The process proceeds from step s6 in FIG. 2 to step s61 in FIG.
[0084]
[Fan abnormality determination; Fig. 9]
In step s61, it is determined whether or not the elapsed time from the start is within a predetermined time (1 minute). If the elapsed time is within the predetermined time (YES), the process proceeds to step s62. Proceed to step s63.
[0085]
In step s62, it is determined that the heat pump cycle H is normal, and the process proceeds to step s7 in FIG. In step s63, it is determined whether or not the refrigerant discharge temperature Tco is high. If the refrigerant discharge temperature Tco is high (YES), the process proceeds to step s64, and if the refrigerant discharge temperature Tco is low (NO), the process proceeds to step s62.
[0086]
In step s64, it is determined whether or not the opening of the expansion valve 3 is fully open. If the opening is not fully open (NO), the process proceeds to step s65. If the opening is fully open (YES), step s66 is performed. Proceed to
[0087]
In step s65, the expansion valve 3 is controlled in the opening direction, and the process proceeds to step s7 in FIG. In step s66, it is determined that the fan motor that drives the outdoor fan 41 has failed or the air heat exchanger 4 has become blocked, and the process proceeds to step s7 in FIG.
[0088]
The hot water supply apparatus D of the present embodiment has the following advantages.
When the controller of the hot water supply device D is activated and the refrigerant discharge temperature Tco is high (however,> 1 minute) and the expansion valve 3 is fully open, the fan motor that drives the outdoor fan 41 has failed, Or it is the structure which discriminate | determines that the air heat exchanger 4 has the obstruction | occlusion failure (it is YES at step s64).
[0089]
As a result, if the fan motor that drives the outdoor fan 41 has failed or if the air heat exchanger 4 has a blocking failure, the fan motor has failed or the air heat exchanger 4 has a blocking failure. Therefore, the hot water supply device D is excellent in maintainability.
[0090]
  The present invention includes the following embodiments in addition to the above embodiments.
a. In each of the above embodiments, the refrigerant pressure is estimated from the deviation and rate of change of the refrigerant discharge temperature sensor 422, but the refrigerant discharge pressure may be directly detected by a pressure sensor..
[Brief description of the drawings]
FIG. 1 of the present inventionFirst reference example, first to thirdIt is explanatory drawing of the hot water supply apparatus which concerns on an Example.
FIG. 2 is a flowchart of control performed by a controller of each hot water supply apparatus.
FIG. 3 FirstreferenceIt is a flowchart which concerns on the expansion valve control of the example hot water supply apparatus.
FIG. 4 FirstreferenceIt is a flowchart which concerns on the expansion valve abnormality determination of the example hot water supply apparatus.
FIG. 5 FirstreferenceIt is a flowchart which concerns on pump control of the example hot water supply apparatus.
FIG. 6 FirstreferenceIt is a flowchart which concerns on pump abnormality determination of the example hot water supply apparatus.
FIG. 71It is a flowchart which concerns on the expansion valve abnormality determination of the hot water supply apparatus of an Example.
FIG. 82It is a flowchart which concerns on compressor control & abnormality determination of the hot water supply apparatus of an Example.
FIG. 93It is a flowchart which concerns on the fan control & abnormality determination of the hot water supply apparatus of an Example.
[Explanation of symbols]
AD water heater
H Heat pump cycle
W Hot water circuit
1 Compressor (refrigerant compressor)
2 Water refrigerant heat exchanger
3 Expansion valve
4 Air heat exchanger
5 Hot water storage tank (tank)
6 Circulation pump
21 Refrigerant flow path
22 Hot water flow path
41 Outdoor fan
42 Refrigerant piping
51 Hot water piping
412 Frost temperature sensor (frost sensor)
422 Refrigerant discharge temperature sensor (pressure abnormality detection means)
512 Hot water temperature sensor (hot water temperature detection means)

Claims (3)

A heat pump cycle in which a refrigerant compressor, a refrigerant flow path of a water refrigerant heat exchanger, an expansion valve, and an air heat exchanger are annularly connected by a refrigerant pipe;
A hot water circuit having a tank for storing hot water, connecting the tank and the hot water flow path of the water refrigerant heat exchanger with a hot water supply pipe, and a circulation pump interposed in the hot water supply pipe;
In a hot water supply apparatus comprising a controller for controlling energization of the circulation pump, the expansion valve, and the refrigerant compressor within predetermined control ranges so that the temperature of hot water supplied to the tank becomes a predetermined temperature.
Even if the controller controls the circulation pump, the expansion valve, and the refrigerant compressor to the limit of each predetermined control range, the temperature of the hot water is a predetermined temperature until a predetermined time elapses after the apparatus is started. If the temperature does not reach the value, it is determined that the heat pump cycle has failed . The hot water supply apparatus according to claim 1,
When the temperature of the hot water supplied to the tank does not reach a predetermined temperature, the controller attempts to increase the hot water temperature by reducing the flow rate of the circulation pump,
When the pump flow rate reaches the lower limit of the control range, the opening of the expansion valve is controlled in the closing direction to try to increase the hot water temperature,
When the opening degree of the expansion valve reaches the lower limit opening degree, it is attempted to increase the temperature of the hot water by controlling the direction of increasing the capacity of the refrigerant compressor,
  Even if the capacity of the refrigerant compressor reaches the upper limit of the control range, if the temperature of hot water supplied to the tank does not reach a predetermined temperature and the refrigerant discharge temperature is low, a heat pump cycle failure including an expansion valve open failure may occur. A hot water supply apparatus, characterized in that it is determined that it has occurred. The hot water supply apparatus according to claim 1,
The air heat exchanger is provided with an outdoor fan,
The controller performs energization control of the circulation pump, the expansion valve, the outdoor fan, and the refrigerant compressor within predetermined control ranges so that the temperature of hot water supplied to the tank becomes a predetermined temperature. ,
Even if the circulation pump, the expansion valve, the outdoor fan, and the refrigerant compressor are controlled to the limit of each predetermined control range until a predetermined time elapses after starting the apparatus, the temperature of the hot water rises. If the refrigerant discharge temperature does not increase and the refrigerant discharge temperature does not rise, it is determined that the refrigerant compressor or its drive circuit has failed .

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