JP2017156062A - Hot water system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hot water system capable of performing hot water supply at lower running cost by combination of a heat pump and an auxiliary heat source machine.SOLUTION: A boiling control part 123 actuates a tank circulation pump 66 before first predetermined time from hot water filling start estimated time, and also, actuates a heat pump 51 at first capacity, and starts a first boiling operation for heating hot water in a hot water storage tank 11. During the execution of the hot water filling operation, when a hot water storage amount of the hot water storage tank 11 recognized by a hot water storage amount recognition part 124 becomes equal to or less than a first hot water storage amount, the boiling control part actuates the tank circulation pump 66, and also, actuates the heat pump 51 at second capacity which has a larger heating amount and lower energy efficiency than the first capacity, and executes a second boiling operation for heating the hot water in the hot water storage tank 11.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a hybrid hot water supply system including a heat pump for boiling water in a hot water storage tank and an instantaneous heating type auxiliary heat source machine as a heat source.

  Conventionally, a so-called hybrid hot water supply system including a heat pump for heating hot water in a hot water storage tank and an instantaneous heating type auxiliary heat source device for heating hot water flowing through a hot water pipe connected to the hot water storage tank is known. (For example, refer to Patent Document 1).

  In the hot water supply system described in Patent Document 1, the first hot water on the day when the water in the hot water storage tank is to be boiled up based on the past hot water usage in units of one day (from 0:00 to 24:00). The time when the supply of hot water starts (hot water supply start time), the time when hot water filling to the bathtub starts (hot water start time), and the time when the last hot water supply ends (hot water supply end time) are assumed. .

  Then, heating of the water in the hot water storage tank is started by the heat pump so that the boiling of the water in the hot water storage tank is finished at the hot water supply start time and the hot water filling start time assumed in this way, and the hot water supply end time is exceeded. The heat pump is stopped after the time before the predetermined time.

JP 2013-224762 A

  According to the hot water supply system described in Patent Document 1, it can be expected that the water in the hot water storage tank is boiled at an appropriate timing to supply hot water by a relatively simple control method based on the past use situation of hot water. In a hybrid hot water supply system, it is desired to perform hot water supply with a lower running cost by combining a heat pump and an auxiliary heat source machine.

  This invention is made | formed in view of this background, and it aims at providing the hot-water supply system which can perform hot-water supply with a lower running cost by the combination of a heat pump and an auxiliary heat source machine.

The hot water supply system of the present invention is
A hot water storage tank in which a water supply pipe is connected to the lower part and a hot water discharge pipe is connected to the upper part, and water supplied from the water supply pipe is stored,
A tank circulation path connecting the lower and upper parts of the hot water storage tank;
A tank circulation pump for circulating hot water stored in the lower part of the hot water storage tank to the upper part of the hot water storage tank via the tank circulation path;
A heat pump for heating hot water flowing through the tank circulation path;
A hot water storage amount recognition unit for recognizing the amount of hot water stored in the hot water storage tank;
A water amount sensor for detecting the flow of hot water from the hot water storage tank to the hot water pipe;
A hot water temperature sensor for detecting the temperature of hot water supplied from the hot water pipe;
Instantaneous heating type auxiliary heat source machine for heating hot water flowing through the hot water pipe,
A hot-water pipe that branches off from the hot water pipe on the downstream side of the heating spot by the auxiliary heat source unit and communicates with the bathtub;
A filling valve for opening and closing the filling pipe;
A hot water filling control unit that performs a hot water filling operation for opening the hot water filling valve and supplying hot water in the hot water storage tank to the bathtub through the hot water filling pipe according to a hot water filling start operation by a user; ,
Auxiliary heat source that activates the auxiliary heat source when the flow rate of hot water from the hot water storage tank to the tapping pipe is detected by the water amount sensor and the temperature detected by the tapping temperature sensor is lower than a predetermined target hot water supply temperature Machine control unit,
An assumed hot water start time setting unit for setting an assumed hot water start time, which is an assumed time at which the hot water operation on the day is started,
A first boiling operation for heating the hot water in the hot water storage tank is started by operating the tank circulation pump and the heat pump with a first capacity before a first predetermined time before the hot water filling start time. When the amount of hot water stored in the hot water storage tank recognized by the hot water storage amount recognition unit falls below the first hot water storage amount during execution of the hot water filling operation by the hot water filling control unit, the tank circulation pump is operated. And a second boiling point for heating the hot water in the hot water storage tank by operating the heat pump with a second capacity that is higher in heating amount and lower in energy efficiency with respect to the hot water flowing through the tank circulation path than the first capacity. And a boiling control unit for performing a lifting operation.

  In the hot water supply system of the present invention, the hot water in the hot water storage tank is heated and heated by the heat pump, and hot water from the outlet pipe can be continued by the operation of the auxiliary heat source machine even if the hot water storage tank runs out. .

  Moreover, the expected hot water start time is set by the expected hot water start time setting unit, and the boiling control unit is more energy efficient than the second capacity for the heat pump before the first predetermined time before the expected hot water start time. The first boiling operation to be operated with the first capacity is started. Thereby, the hot water in the hot water storage tank can be efficiently boiled up to the start of the hot water filling operation to prepare for the start of the hot water filling operation. In addition, when the hot water filling operation is started and the amount of hot water stored in the hot water storage tank becomes equal to or less than the first hot water storage amount, the boiling control unit heats the hot water flowing through the tank circulation path more than the first capacity. The second boiling operation that is operated with the second ability with a large amount is performed. As a result, the hot water in the hot water storage tank is heated quickly, and the operating time of the instantaneous heating type auxiliary heat source machine, which is less energy efficient than the heat pump and expensive in running cost, is shortened, and the running cost of hot water filling operation is reduced. Can be achieved.

  In addition, the day in this invention means the day when the planned boiling of the hot water in the hot water storage tank based on the hot water filling start assumption time and the hot water supply start assumption time will be performed from now on.

  In the boiling control unit, during the hot water filling operation by the hot water filling control unit, the hot water storage amount in the hot water storage tank recognized by the hot water storage amount recognition unit becomes equal to or less than the first hot water storage amount. Sometimes, the second boiling operation is executed for a second predetermined time, and thereafter, the first boiling operation is switched to.

  According to this configuration, the heat pump is switched from the second boiling operation to the first boiling operation when the amount of hot water stored in the hot water storage tank is secured to some extent by the execution of the second boiling operation. The running time of the second boiling operation in which the energy efficiency of the second boiling operation is lower than that of the first boiling operation can be shortened, and the running cost can be reduced.

In addition, a hot water supply end expected time setting unit for setting a hot water supply end estimated time that is an assumed time at which use of hot water on the day ends is provided,
The boiling control unit stops the heat pump until the next day after the boiling operation end time that is a third predetermined time before the estimated hot water supply end time, and the hot water filling operation by the hot water control unit performs the boiling operation. The second boiling operation is executed only when it is started before a time that is a fourth predetermined time before the operation end time, and the hot water filling operation by the hot water control unit is performed at the boiling operation end time. When starting after the time before the fourth predetermined time, only the first boiling operation is executed.

  According to this configuration, when the hot water filling operation is started after the fourth predetermined time before the boiling operation end time, the boiling operation end time is soon reached even if the hot water filling operation is switched to the second boiling operation. Since the heat pump stops, there is a high possibility that the hot water storage tank will run out and the auxiliary heat source unit will operate.

  Therefore, in this case, by continuing the first boiling operation without switching to the second boiling operation, the second boiling operation is performed for a short time by switching to the second boiling operation. A decrease in energy efficiency of the heat pump can be suppressed.

In addition, a hot water supply start expected time setting unit for setting a hot water supply start estimated time, which is an assumed time at which use of hot water on the day is started,
The boiling control unit activates the tank circulation pump and activates the heat pump with a third capacity to heat the hot water in the hot water storage tank at a fifth predetermined time before the estimated hot water supply start time. When the third boiling operation is started and the flow of hot water from the hot water storage tank to the outlet pipe is detected by the water amount sensor during the execution of the third boiling operation, the tank circulation pump is operated. The heat pump is operated at a fourth capacity that has a larger heating amount for the hot water flowing through the tank circulation path than the third capacity, and is switched to a fourth boiling operation for heating the hot water in the hot water storage tank. And

  According to this configuration, when the third boiling operation is performed from the fifth predetermined time before the estimated hot water supply start time, when the flow of hot water from the hot water storage tank to the hot water discharge pipe is detected by the water amount sensor, By switching to the fourth boiling operation in which the amount of heating with respect to the hot water flowing through the tapping pipe is larger than that in the third boiling operation, the hot water in the hot water storage tank can be quickly heated to cope with the use of hot water. Thereby, the action | operation of an auxiliary heat source machine can be suppressed and the running cost of hot water supply can be reduced.

  In addition, after the boiling controller detects the flow of hot water from the hot water storage tank to the tap pipe during the execution of the third boiling operation, and switches to the fourth boiling operation. The hot water storage amount recognized by the hot water storage amount recognition unit is returned to the third boiling operation when the hot water storage amount in the hot water storage tank becomes equal to or higher than the second hot water storage amount.

  According to this configuration, after the amount of hot water stored in the hot water storage tank becomes equal to or greater than the second amount of hot water stored by the execution of the fourth boiling operation, the operation is returned to the third boiling operation. Thereby, the boiling time of the hot water in the hot water storage tank can be reduced by reducing the time required for the fourth boiling operation in which the energy efficiency of the heat pump is lower than that of the third boiling operation, thereby reducing the running cost. .

  In addition, after the boiling controller detects the flow of hot water from the hot water storage tank to the tap pipe during the execution of the third boiling operation, and switches to the fourth boiling operation. When the sixth predetermined time has elapsed, the third boiling operation is returned to.

  According to this configuration, after the amount of hot water in the hot water storage tank has increased to some extent by the execution of the fourth boiling operation for the sixth predetermined time, the operation is returned to the third boiling operation. Thereby, the boiling time of the hot water in the hot water storage tank can be reduced by reducing the time required for the fourth boiling operation in which the energy efficiency of the heat pump is lower than that of the third boiling operation, thereby reducing the running cost. .

  Further, the boiling control unit is executing the third boiling operation, and within a seventh predetermined time from the start of the third boiling operation, the water amount sensor transfers the hot water storage tank to the outlet pipe. Only when the flow of hot water is detected, switching to the fourth boiling operation is performed, and after the seventh predetermined time has elapsed from the start of the third boiling operation, the water amount sensor When the circulation of hot water from the hot water storage tank to the hot water discharge pipe is detected, the third boiling operation is continued without switching to the fourth boiling operation.

  According to this configuration, after a certain amount of hot water is stored in the hot water storage tank by executing the third boiling operation for the seventh predetermined time, the third boiling is performed without switching to the fourth boiling operation. By continuing the operation, it is possible to prevent the energy efficiency of the heat pump from being lowered due to the switching to the fourth boiling operation and the short-time execution of the fourth boiling operation.

  In addition, the boiling control unit is executing the third boiling operation, and the hot water storage amount recognized by the hot water storage amount recognition unit is equal to or less than the third hot water storage amount, Only when the flow of hot water from the hot water storage tank to the hot water pipe is detected by the water amount sensor, switching to the fourth boiling operation is performed, and the hot water storage tank is recognized by the hot water storage amount recognition unit. In the state where the amount of stored hot water is larger than the third amount of stored hot water, when the water amount sensor detects the flow of hot water from the hot water storage tank to the tapping pipe, the switching to the fourth boiling operation is not performed. The third boiling operation is continued.

  According to this configuration, when the amount of hot water in the hot water storage tank is already larger than the third stored amount due to the execution of the third boiling operation, the third boiling operation is not performed without switching to the fourth boiling operation. By continuing the raising operation, it is possible to prevent the energy efficiency of the heat pump from being lowered due to the switching to the fourth boiling operation and the short-time execution of the fourth boiling operation.

The block diagram of a hot-water supply system. Flow chart of boiling operation. The flowchart of the heating operation during a hot water operation. The flowchart of the heating operation based on hot water supply start assumption time. The 1st explanatory view showing the execution timing of boiling operation, and the use situation of hot water. The 2nd explanatory view showing the execution timing of boiling operation, and the use situation of hot water. 3rd explanatory drawing which showed the execution timing of boiling operation, and the use condition of hot water.

  An embodiment of the present invention will be described with reference to FIGS.

[1. Configuration of hot water supply system]
With reference to FIG. 1, the hot water supply system 1 of the present embodiment includes a hot water storage unit 10, a heat pump unit 50, an auxiliary heat source unit 80, and a controller 120 that controls the overall operation of the hot water supply system 1. This is a hybrid hot water supply system.

  In FIG. 1, one controller 120 is shown as the controller of the hot water supply system 1. However, the controller of the hot water storage unit 10, the controller of the heat pump unit 50, and the controller of the auxiliary heat source unit 80 are provided separately, It is good also as a structure which controls the whole action | operation of the hot water supply system 1 by communication.

  The hot water storage unit 10 includes a hot water storage tank 11, a water supply pipe 12, a hot water discharge pipe 13, and the like. The hot water storage tank 11 keeps hot water inside and stores the hot water inside the tank. The hot water storage tank 11 is disposed at substantially equal intervals in the height direction, and detects the temperature th2 to th5 of the hot water in the hot water storage tank 11 at each height. 17 and an in-tank temperature sensor 26 that is disposed above the hot water storage tank 11 and detects the temperature th1 of hot water supplied from the hot water storage tank 11 to the hot water discharge pipe 13 is provided.

  Further, in the vicinity of the connection point between the lower part of the hot water storage tank 11 and the lower part of the hot water storage tank 11 in the tank circulation path 41 connecting the upper part and the lower part of the hot water storage tank 11, the tank lower temperature for detecting the temperature th6 of hot water stored in the lower part of the hot water storage tank 11 A sensor 42 is provided. A drain valve 18 is provided at the bottom of the hot water storage tank 11 and is opened by an operator's manual operation.

  One end of the water supply pipe 12 is connected to a water supply (not shown) via a water supply port 30, and the other end is connected to the lower part of the hot water storage tank 11 to supply water to the lower part of the hot water storage tank 11. The water supply pipe 12 allows water to flow only in the direction from the water supply pipe 12 to the hot water storage tank 11 by preventing the internal pressure of the hot water storage tank 11 from becoming excessive, and to supply water from the hot water storage tank 11. A first hot water side check valve 20 is provided to prevent outflow of hot water to the pipe 12 side.

  A water supply bypass pipe 34 branched from the water supply pipe 12 communicates with the hot water discharge pipe 13 at the connection point X via the hot water supply mixing valve 21, and hot water supplied from the hot water storage tank 11 to the hot water supply pipe 13 by the hot water supply mixing valve 21. The mixing ratio with the water supplied from the feed water bypass pipe 34 to the hot water discharge pipe 13 is changed.

  The water supply bypass pipe 34 detects the temperature Tw of water supplied to the water supply bypass pipe 34 (hereinafter referred to as the water supply temperature Tw) and the flow rate Fw of water flowing through the water supply bypass pipe 34. The water-side flow rate sensor 23 and a water-side check valve 24 that allows water flow only in the direction from the water supply bypass pipe 34 to the hot water supply pipe 13 and prevents outflow of hot water from the hot water supply pipe 13 to the water supply bypass pipe 34 side. And are provided.

  The hot water discharge pipe 13 has one end connected to the hot water supply port 31 and the other end connected to the upper part of the hot water storage tank 11. Hot water stored in the upper part of the hot water storage tank 11 is supplied from a hot water outlet pipe 13 to a hot water tap (not shown) (kitchen, washroom, bathroom currant, shower, etc.) via a hot water outlet 31. A second hot water side check valve 25 that allows the hot water pipe 13 to pass water only in the direction from the hot water storage tank 11 to the hot water discharge pipe 13 and prevents the hot water from flowing into the hot water storage tank 11 side from the hot water storage pipe 11. A hot water flow rate sensor 27 for detecting the flow rate Fh of hot water supplied from the hot water storage tank 11 to the hot water discharge pipe 13 is provided.

  The auxiliary heat source unit 80 is provided in the middle of the downstream side of the connection point X with the feed water bypass pipe 34 of the tap water pipe 13, and the hot water storage unit 10 bypasses the auxiliary heat source unit 80 and is downstream of the auxiliary heat source unit 80. A hot water bypass pipe 33 that connects the hot water outlet pipe 13 to the upstream side and a hot water bypass valve 29 that opens and closes the hot water bypass pipe 33 are provided.

  A mixing temperature sensor 28 for detecting the temperature Tm of hot water supplied to the hot water supply pipe 13 through the hot water supply mixing valve 21 is provided between the hot water supply mixing valve 21 and the branch point Y of the hot water supply pipe 13 with the hot water supply bypass pipe 33. A hot water supply temperature sensor 32 that detects the temperature of the hot water discharged from the hot water supply port 31 is provided between the joining point Z of the hot water supply pipe 13 and the hot water supply bypass pipe 33 and the hot water supply port 31.

  Detection signals from the sensors provided in the hot water storage unit 10 are input to the controller 120. Further, the operation of the hot water supply mixing valve 21 and the hot water bypass valve 29 is controlled by a control signal output from the controller 120.

  Next, the heat pump unit 50 circulates the hot water in the hot water storage tank 11 through the tank circulation path 41 and heats it, and is installed outdoors. The heat pump unit 50 includes an evaporator 53, a compressor 54, and a heat pump heat exchanger 55 (condenser) connected by a heat pump circuit 52 in which a heat medium (alternative fluorocarbon such as hydrofluorocarbon (HFC), carbon dioxide, etc.) is enclosed. ) And an expansion valve 56.

  The evaporator 53 performs heat exchange between the air (outside air) supplied by the rotation of the fan 60 and the heat medium circulating in the heat pump circuit 52. The compressor 54 compresses the heat medium discharged from the evaporator 53 to high pressure and high temperature, and sends it to the heat pump heat exchanger 55. The expansion valve 56 releases the pressure of the heat medium pressurized by the compressor 54.

  The defrost valve 61 is provided so as to bypass the expansion valve 56, and defrosts the evaporator 53 with a heat medium sent from the compressor 54. Heat medium temperature sensors 62, 63 for detecting the temperature of the heat medium circulating in the heat pump circuit 52 are provided upstream and downstream of the expansion valve 56 of the heat pump circuit 52 and upstream and downstream of the compressor 54. 64 and 65 are provided, respectively. Further, the evaporator 53 is provided with an ambient temperature sensor 67 that detects the temperature Tout of the air sucked into the evaporator 53.

  The heat pump heat exchanger 55 is connected to the tank circulation path 41, and circulates in the tank circulation path 41 by heat exchange between the heat medium that has been increased in pressure and temperature by the compressor 54 and hot water flowing in the tank circulation path 41. Heat the hot water. The tank circulation path 41 is provided with a tank circulation pump 66 for circulating hot water in the hot water storage tank 11 through the tank circulation path 41.

  Hot water stored in the lower part of the hot water storage tank 11 is guided to the tank circulation path 41 by the tank circulation pump 66, heated to a predetermined temperature (boiling temperature) by the heat pump heat exchanger 55, and returned to the upper part of the hot water storage tank 11. . Thereby, hot water of a predetermined temperature is sequentially stacked from the upper part of the hot water storage tank 11 and stored.

  Note that hot water temperature sensors 68 and 69 for detecting the temperature of hot water flowing in the tank circulation path 41 are provided on the upstream side and the downstream side of the heat pump heat exchanger 55 in the tank circulation path 41. Further, the heat pump heat exchanger 55 is provided with a condensing temperature sensor 57 for detecting the condensing temperature of the heat medium condensing therein.

  Detection signals from the sensors provided in the heat pump unit 50 are input to the controller 120. The operation of the compressor 54, the expansion valve 56, the tank circulation pump 66, and the fan 60 is controlled by a control signal output from the controller 120.

  Next, the auxiliary heat source unit 80 is for heating hot water flowing through the hot water discharge pipe 13, and includes a hot water supply burner 81 housed in the can body 87, a hot water supply heat exchanger 82 heated by the hot water supply burner 81, and the like. ing.

  A hot water filled pipe 100 communicating with the bathtub 105 is connected to a location downstream of the hot water supply heat exchanger 82 in the hot water discharge pipe 13. The hot water filling pipe 100 is provided with a hot water filling valve 103 for opening and closing the hot water filling pipe 100, and the controller 120 opens the hot water filling valve 103 to open the hot water filling pipe 103 through the hot water filling pipe 100. Hot water is supplied to the bathtub 105.

  Fuel gas is supplied to the hot water supply burner 81 from a gas supply pipe (not shown), and combustion air is supplied from a combustion fan (not shown). The controller 120 controls the amount of combustion of the hot water supply burner 81 by adjusting the flow rates of the fuel gas and the combustion air supplied to the hot water supply burner 81.

  The hot water supply heat exchanger 82 is connected in the middle of the hot water discharge pipe 13, and heats the hot water flowing inside by the combustion heat of the hot water supply burner 81. The hot water discharge pipe 13 is provided with a water stop valve 93 and a water amount sensor 88 in order from the upstream side. The upstream side and the downstream side of the hot water supply heat exchanger 82 are connected by a heat source bypass pipe 89, and the heat source bypass pipe 89 is provided with a heat source bypass valve 90 for adjusting the opening degree of the heat source bypass pipe 89. Yes. A heat exchanger hot water temperature sensor 91 is provided in the vicinity of the outlet of the hot water supply heat exchanger 82 of the hot water discharge pipe 13, and a heat source hot water temperature sensor 92 (in accordance with the present invention) is provided downstream of the location of the hot water supply pipe 13 connected to the heat source bypass pipe 89. Corresponding to a tapping temperature sensor).

  With this configuration, when there is no hot water in the hot water storage tank 11 (when the hot water is in a hot state), the water supplied from the water supply pipe 12 to the hot water discharge pipe 13 via the hot water storage tank 11 and the water supply bypass pipe 34 is hot water supply heat. Hot water is heated by the exchanger 82 to be mixed with water from the heat source bypass pipe 89, and hot water having a target hot water supply temperature is supplied from the hot water supply port 31.

  The detection signal of each sensor provided in the auxiliary heat source device 80 is input to the controller 120. Further, the operation of the hot water supply burner 81, the heat source bypass valve 90, and the hot water filling valve 103 is controlled by a control signal output from the controller 120.

  The controller 120 is an electronic circuit unit configured by a CPU, a memory, and the like (not shown), and by executing a control program for the hot water supply system 1 held in the memory by the CPU, the hot water supply control unit 121 and the hot water filling control unit 122, a boiling control unit 123, a hot water storage amount recognition unit 124, an assumed hot water supply start time setting unit 125, an assumed hot water start time setting unit 126, and an assumed hot water supply end time setting unit 127.

  The controller 120 is connected to the remote controller 140 via a communication cable 130. The remote controller 140 includes a display 141 for displaying the operation status of the hot water supply system 1, setting of operation conditions, and the like, and a switch unit 142 provided with various switches. The user of the hot water supply system 1 operates the switch unit 142 of the remote controller 140 to set the hot water supply temperature (target hot water supply temperature) from the hot water supply port 31 and the hot water supply temperature to the bathtub 105 in the hot water filling operation (target hot water filling). Temperature) and hot water filling amount (target hot water filling amount) are set.

  When the hot water storage tank 11 has not run out of hot water and the water-side flow rate sensor 23 detects water flow exceeding the lower limit flow rate, the hot water supply control unit 121 determines whether the mixed temperature sensor 28 or the hot water supply temperature sensor 32 Mixing temperature adjustment control is performed to adjust the distribution ratio of the hot water supply mixing valve 21 so that the detected temperature becomes the target hot water supply temperature. At this time, the hot water supply control unit 121 closes the hot water bypass valve 29 when the hot water filling valve 103 is opened and hot water is supplied to the bathtub 105, and when the hot water filling valve 103 is closed. The hot water bypass valve 29 is opened.

  Further, the hot water supply control unit 121 closes the hot water bypass valve 29 when the hot water storage tank 11 has run out of water and the water flow rate sensor 23 detects water flow exceeding the lower limit flow rate. . Heating temperature control for adjusting the combustion amount of the hot water supply burner 81 so that the temperature detected by the heat source hot water temperature sensor 92 becomes the target hot water supply temperature when water flow exceeding the lower limit flow rate is detected by the water amount sensor 88. Execute. The configuration in which the hot water supply control unit 121 performs the heating temperature control in this way corresponds to the auxiliary heat source unit control unit of the present invention.

  The hot water filling control unit 122 ends the hot water filling to the bathtub 105 when an operation for instructing hot water filling (hot water filling start operation) is performed by the switch unit 142 of the remote controller 140 or at a preset reserved time. Thus, the hot water filling operation is performed in which the hot water filling valve 103 is opened and the hot water filling pipe 13 supplies hot water for the target hot water amount to the bathtub 105 via the hot water filling pipe 100. The hot water filling control unit 122 sets the target hot water filling temperature to the target hot water supply temperature, and executes the hot water filling operation.

  The hot water storage amount recognition unit 124 recognizes the amount of hot water stored in the hot water storage tank 11 (hot water storage amount) by monitoring the temperature detected by the tank temperature sensor 26 and the tank surface temperature sensors 14 to 17. It should be noted that the hot water supply flow rate from the hot water storage tank 11 to the tapping pipe 13 is determined from the total amount of hot water in the hot water storage tank 11 (= capacity of the hot water storage tank 11) in a state where the boiling of the hot water storage tank 11 is completed (full storage state). It is also possible to recognize the amount of stored hot water by subtracting the integrated value (detected by the hot water flow rate sensor 27) or by subtracting the estimated hot water supply amount from the hot water supply time from the hot water storage tank 11 to the hot water outlet pipe. Good.

  The boiling control unit 123 operates the tank circulation pump 66 and the heat pump 51 when the remaining amount of hot water in the hot water storage tank 11 recognized by the hot water storage amount recognition unit 124 becomes equal to or lower than the lower limit amount. A boiling operation is performed in which the hot water in the inside is heated to, for example, 45 ° C. according to the set hot water supply temperature.

  In addition, the boiling control unit 123 executes planned boiling of hot water in the hot water storage tank 11 in order to ensure the amount of hot water stored in the hot water storage tank 11 in preparation for a time zone in which hot water is expected to be used.

[2. Systematic boiling of hot water in a hot water storage tank]
Next, execution of planned boiling of hot water in the hot water storage tank 11 will be described according to the flowcharts shown in FIGS.

  Referring to FIG. 2, controller 120 determines whether or not the current time (recognized by a timing circuit not shown) has reached the date update timing (2 o'clock) in STEP 1. Then, when the current time comes to the date update timing, the process proceeds to STEP2.

  STEP 2 is processing by the hot water supply start estimated time setting unit 125, the hot water filling start estimated time setting unit 126, and the hot water supply end estimated time setting unit 127. The controller 120 stores past hot water usage data (hot water supply status data) in units of one day (from 0:00 to 24:00), and the hot water start expected time setting unit 125 is based on the hot water supply status data. An assumed hot water supply start time S1, which is a time at which the use of hot water on the day (the day on which a planned boiling operation is to be executed) is assumed to start, is set.

  Similarly, the expected hot water filling start time setting unit 126 sets an estimated hot water filling start time B1, which is a time at which the hot water filling operation is assumed to be started on the day, based on the hot water supply status data. Also, hot water supply end estimated time setting unit 127 sets hot water supply end estimated time G1, which is a time at which use of hot water is assumed to end on the day, based on hot water supply status data.

  Here, in FIG. 5, the horizontal axis is a common time axis, the vertical axis is set as the capacity of the heat pump 51 in the upper stage, and the execution timing of the heating operation in the time zone of one day (0 to 24:00) is shown. In the lower part of the figure, the vertical axis is set to the hot water supply flow rate (detected by the water amount sensor 88), and the amount of hot water used (hot water supply flow rate) in the time zone of one day (from 0:00 to 24:00) is illustrated. . In the example of FIG. 5, 2:00 is set as the date update timing, the hot water supply start estimated time S1 is set at 6:00, the hot water filling start estimated time B1 is set at 20:00, and the hot water supply end estimated time G1 is set at 24:00.

  STEP 3 to STEP 8 in FIG. 2 are processes by the boiling control unit 123. In step 3, the boiling control unit 123 waits for the current time to be a time S0 (refer to FIG. 5) that is α (corresponding to a fifth predetermined time of the present invention) before the hot water supply start estimated time S1. Then, the first boiling operation (corresponding to the first boiling operation and the third boiling operation of the present invention) is executed to boil the hot water in the hot water storage tank 11.

  Here, in the first boiling operation, the tank circulating pump 66 is operated, and the heat pump 51 is operated with the first capacity A1 (corresponding to the first capacity and the third capacity of the present invention), whereby the hot water storage tank 11 is operated. Heat the hot water inside. In this case, the circulating water flow rate of the tank circulation pump 66 is adjusted so that the temperature detected by the hot water temperature sensor 69 becomes the boiling temperature. Further, α is set so that boiling of hot water in the hot water storage tank 11 is completed at the estimated hot water supply start time S1.

  In the present embodiment, both the heating based on the estimated hot water supply start time S1 executed in STEP 4 and the boiling based on the estimated hot water start time B1 executed in STEP 6 described later have the capability of the heat pump 51. Although it is performed by the first boiling operation with 1 capability A1, the capability of the heat pump 51 may be varied.

  In this case, the capability of the heat pump 51 when boiling based on the estimated hot water supply start time S1 corresponds to the third capability of the present invention, and the boiling operation at the third capability is equivalent to the third boiling operation of the present invention. Equivalent to. Moreover, the capability of the heat pump 51 when performing boiling based on the expected hot water filling start time B1 corresponds to the first capability of the present invention, and the boiling operation by the first capability corresponds to the first boiling operation of the present invention. To do.

  When the boiling of the hot water in the hot water storage tank 11 by the first boiling operation is completed in STEP4, the process proceeds to STEP5. Then, the boiling control unit 123 waits for the time B0 (see FIG. 5), which is a time β (corresponding to the first predetermined time of the present invention) before the hot water filling start time B1 in STEP5. Then, the process proceeds to STEP 6 where the first boiling operation is executed to boil the hot water in the hot water storage tank 11. Here, β is set such that boiling of the hot water in the hot water storage tank 11 is completed at the expected hot water filling start time B1.

  In the next STEP 7, after waiting for the current time to be a time G0 (boiling operation end time) γ (assumed to be the third predetermined time of the present invention) before the hot water supply end estimated time G1, the process proceeds to STEP 8. The boiling control unit 123 maintains the heat pump 51 in a stopped state until the next day.

  In the example shown in FIG. 5, around 6 o'clock (wake-up to breakfast time), around 12:00 (lunch time), around 20:00 (bath-bathing time), around 24:00 (before bedtime) Hot water is used during the time period.

[3. Boiling hot water in a hot water storage tank during hot water operation]
Next, the process of boiling hot water in the hot water storage tank 11 executed by the boiling control unit 123 in accordance with the hot water filling operation will be described with reference to the flowchart shown in FIG.

  The boiling control unit 123 determines whether or not the hot water filling operation is being performed in STEP 10 of FIG. 3. Then, the process proceeds to STEP 11 when the hot water filling operation is in progress, and the boiling control unit 123 determines whether or not the hot water storage amount in the hot water storage tank 11 recognized by the hot water storage amount recognition unit 124 is equal to or less than the first hot water storage amount. To do. When the hot water storage amount in the hot water storage tank 11 is less than or equal to the first hot water storage amount, the process proceeds to STEP 12, and when the hot water storage amount in the hot water storage tank 11 is larger than the first hot water storage amount, the process returns to STEP 10.

  Here, according to the supply of hot water from the hot water storage tank 11 to the hot water discharge pipe 13, the first hot water storage amount is such that the water supply pipe 12 is supplied to the lower part of the hot water storage tank 11, and the energy efficiency of boiling by the heat pump 51 is It is set assuming a situation where the level exceeds a predetermined level.

  In STEP 12, the boiling control unit 123 determines whether or not the current time is before e (corresponding to the fourth predetermined time of the present invention) before the boiling operation end time G0. When the current time is before e before the boiling operation end time G0, the process proceeds to STEP13, and when the current time is not e before the boiling operation end time G0, the process branches to STEP20.

  In STEP 13, the boiling control unit 123 operates the tank circulation pump 66 and operates the heat pump 51 with the second capability A <b> 2 to execute a second boiling operation for boiling hot water in the hot water storage tank 11. Here, the 2nd capability A2 has much heating amount provided to the hot water which distribute | circulates the tank circulation path 41 rather than 1st capability A1, and the energy efficiency of the heat pump 51 becomes low.

  The energy efficiency of the heat pump 51 is expressed by, for example, a coefficient of performance COP (heating amount / power consumption).

  As described above, when the hot water storage tank 11 runs out during the hot water filling operation, the second boiling operation is performed in which the heat pump 51 is operated with the second ability A2 having a heating amount higher than the first ability A1. As a result, the boiling speed of the hot water in the hot water storage tank 11 can be increased to shorten the time for which the auxiliary heat source unit 80 operates. As a result, the operating time of the auxiliary heat source unit 80 having a running cost higher than that of the heat pump 51 can be shortened, and the running cost required for the hot water filling operation can be reduced.

  FIG. 5 shows that after the boiling of hot water in the hot water storage tank 11 is completed by the first boiling operation, the hot water filling operation is started and the amount of hot water stored in the hot water storage tank 11 becomes equal to or less than the first hot water storage amount. The case where the raising operation is executed is shown. In the example of FIG. 5, the second boiling operation in which the capability of the heat pump 51 is set to the second capability A2 is continued until the boiling of the hot water in the hot water storage tank 11 is completed.

  In contrast, in the flowchart of FIG. 3, after starting the second boiling operation in STEP 13, the boiling control unit 123 waits for T1 (corresponding to the second predetermined time of the present invention) in STEP 14 to wait for STEP 15. Then, the second boiling operation is switched to the first boiling operation to boil the hot water in the hot water storage tank 11, and the process proceeds to STEP 16 to finish the process.

  FIG. 6 shows that the boiling operation associated with the hot water filling operation is performed as described above, the second boiling operation is executed during the first T1 period (immediately after 20:00 to t3), and the first boiling operation is performed after T1 has elapsed. It shows the case of switching to. By performing the second boiling operation only during the first T1 period, the hot water in the hot water storage tank 11 is quickly boiled and the hot water filling proceeds to some extent or the hot water filling ends. After it is no longer necessary to quickly boil the hot water in the hot water storage tank 11, the energy efficiency of the heat pump 51 can be increased to reduce the running cost required for boiling the hot water in the hot water storage tank 11.

  When branching from STEP 12 to STEP 20, the boiling control unit 123 executes the first boiling operation to boil hot water in the hot water storage tank, and proceeds to STEP 16 for processing. In this case, the second boiling operation is not executed.

  FIG. 7 shows a case where the boiling associated with the hot water filling operation is performed only by the first boiling operation. In the example of FIG. 7, the time t5 at which the hot water filling operation is started is not e before the boiling operation end time G0. Therefore, the first boiling operation in which the heat pump 51 is operated with the first capacity A1 is performed only for a short time. The first boiling operation is finished at the boiling operation end time G0. In this case, since the time for performing the boiling operation by operating the heat pump 51 is short, the timing at which the hot water storage tank 11 runs out due to the hot water filling operation is accelerated, and the hot water filling operation is performed by operating the auxiliary heat source device 80. The time will be longer.

  As described above, even when the second boiling operation is executed for a short time when the time for performing the filling operation by operating the auxiliary heat source device 80 becomes long, the effect obtained by increasing the heating amount of the heat pump 51 is low. Therefore, the total running cost of the hot water supply can be reduced by performing the first boiling operation.

[4. Boiling hot water in a hot water storage tank based on the expected hot water start time]
Next, in accordance with the flowchart shown in FIG. 4, a process for boiling hot water in the hot water storage tank 11 based on the estimated hot water supply start time S <b> 1 executed by the boiling control unit 123 will be described.

  In STEP30 of FIG. 4, the boiling control unit 123 determines whether or not the first boiling operation is being performed based on the estimated hot water supply start time S1, and when the first boiling operation is being performed, STEP31. Proceed to In STEP 31, the boiling control unit 123 determines whether or not the detected flow rate Fm of the water amount sensor 88 is equal to or higher than the lower limit flow rate (whether or not the flow of hot water from the hot water storage tank 11 to the hot water discharge pipe 13 is detected). When the detected flow rate Fm is greater than or equal to the lower limit flow rate, the process proceeds to STEP 32, and when the detected flow rate Fm is less than the lower limit flow rate, the process returns to STEP 30.

  In STEP 32, the boiling control unit 123 determines whether or not d (corresponding to the seventh predetermined time of the present invention) or more has elapsed since the time S0 when the first boiling operation was started. If it is determined that the boiling time of the hot water in the hot water storage tank 11 has not progressed much since d or more has not elapsed since the time S0 at which the first boiling operation was started, the process proceeds to STEP 33 and the second boiling operation is performed. Switch.

  In subsequent STEP 34, T2 (corresponding to the sixth predetermined time of the present invention) waits to proceed to STEP 35, and the boiling control unit 123 returns from the second boiling operation to the first boiling operation to return to the hot water storage tank. The boiling of the hot water in 11 is completed, and it progresses to STEP36 and complete | finishes a process.

  FIG. 6 shows a case where the use of hot water is started at t1 before d elapses from S0 after the first boiling operation in which the heat pump 51 is operated at the first capacity A1 is started at S0. Illustrated. In FIG. 6, the heat pump 51 is switched to the second heating operation that operates at the second capacity A2 at t1, and is returned to the first heating operation at t2 when T2 has elapsed from t1.

  In this way, after starting the first boiling operation at S0, when the use of hot water is started before the boiling of the hot water in the hot water storage tank 11 is completed, by switching to the second boiling operation, By quickly heating the hot water in the hot water storage tank 11, the auxiliary heat source unit 80 can be prevented from operating, and the running cost of hot water can be reduced.

  In addition, at time t <b> 2 when boiling of the hot water in the hot water storage tank 11 has progressed to some extent, the energy efficiency of the heat pump 51 is increased by returning from the second boiling operation to the first boiling operation, so that the hot water in the hot water storage tank 11 is increased. The running cost of boiling can be reduced.

  On the other hand, in STEP 32, when more than d has elapsed from the time S0 at which the first boiling operation is started, the process branches to STEP 40, and the boiling control unit 123 continues the first boiling operation and continues to the hot water in the hot water storage tank 11. Is completed, the process proceeds to STEP 36 and the process is terminated.

  FIG. 7 exemplifies a case where the use of hot water is started at t4 after elapse of d or more from S0 after the first boiling operation in which the heat pump 51 is operated at the first capacity A1 is started at S0. ing. In FIG. 7, even if the use of hot water is started at t4, the first boiling operation is continuously executed without switching to the second boiling operation.

  As described above, after the first boiling operation is started in S0, when the use of hot water is started in a state in which boiling of hot water in the hot water storage tank 11 has progressed to some extent after elapse of d or more, the water has already been boiled. It is assumed that hot water in the hot water storage tank 11 can be used for hot water supply. Therefore, in this case, the first boiling operation is continued without switching to the second boiling operation, thereby avoiding a decrease in energy efficiency of the heat pump 51 associated with the switching to the second boiling operation. Thus, the running cost of hot water supply can be reduced.

  In addition, in this embodiment, when the use of hot water is started during boiling based on the hot water supply start estimated time S1 in STEP32 to STEP33 in FIG. 4 and boiling in the hot water filling operation in STEP12 to STEP13 in FIG. The boiling is performed by the second boiling operation in which the ability of the heat pump 51 is the second ability A2, but the ability of the heat pump 51 may be varied.

  In this case, the capability of the heat pump 51 when boiling is performed in STEP 12 to STEP 13 of FIG. 3 corresponds to the second capability of the present invention, and the boiling operation with the second capability is the second boiling operation of the present invention. Equivalent to. Moreover, the capability of the heat pump 51 when boiling is performed in STEP32 to STEP33 of FIG. 4 corresponds to the fourth capability of the present invention, and the boiling operation by the fourth capability corresponds to the fourth boiling operation of the present invention.

[5. Other Embodiments]
In the above embodiment, in STEP 32 of FIG. 4, when the use of hot water is started before d elapses from the start time S0 of the first boiling operation, it is switched to the second boiling operation. When the use of hot water is started before the hot water storage amount in the hot water storage tank 11 recognized by the amount recognition unit 124 becomes equal to or greater than the third hot water storage amount, it may be switched to the second boiling operation.

  Further, in the above embodiment, at STEP 34 in FIG. 4, when the execution time of the second boiling operation becomes T2 or more, the first boiling operation is returned to, but the hot water storage amount recognition unit 124 recognizes it. When the amount of hot water stored in the hot water storage tank 11 becomes equal to or greater than the second hot water storage amount, the first boiling operation may be returned.

  Moreover, in the said embodiment, although the auxiliary heat source machine 80 which used the hot water supply burner 81 which burns fuel gas as a heating source as an auxiliary heat source machine of this invention was shown, the instantaneous heating type which uses a petroleum burner, an electric heater, etc. as a heating source The auxiliary heat source machine may be used.

  Moreover, in the said embodiment, although the heat pump unit 50 was shown as a heat pump of this invention, not only this structure but a heat pump unit which heats the water which distribute | circulates a tank circulation path, Comprising: What is a variable capacity type heat pump unit? In this case, the present invention can be applied.

  DESCRIPTION OF SYMBOLS 1 ... Hot water supply system, 10 ... Hot water storage unit, 11 ... Hot water storage tank, 12 ... Water supply pipe, 13 ... Hot water discharge pipe, 41 ... Tank circulation path, 50 ... Heat pump unit, 51 ... Heat pump, 66 ... Tank circulation pump, 80 ... Auxiliary heat source , 88 ... Water quantity sensor, 100 ... Hot water filling pipe, 103 ... Hot water filling valve, 105 ... Bathtub, 120 ... Controller, 121 ... Hot water supply control part, 122 ... Hot water filling control part, 123 ... Boiling control part, 124 ... Hot water storage An amount recognition unit, 125 ... an assumed hot water supply start time setting unit, 126 ... an assumed hot water start time setting unit, and 127 ... an assumed hot water supply end time setting unit.

Claims (8)

A hot water storage tank in which a water supply pipe is connected to the lower part and a hot water discharge pipe is connected to the upper part, and water supplied from the water supply pipe is stored,
A tank circulation path connecting the lower and upper parts of the hot water storage tank;
A tank circulation pump for circulating hot water stored in the lower part of the hot water storage tank to the upper part of the hot water storage tank via the tank circulation path;
A heat pump for heating hot water flowing through the tank circulation path;
A hot water storage amount recognition unit for recognizing the amount of hot water stored in the hot water storage tank;
A water amount sensor for detecting the flow of hot water from the hot water storage tank to the hot water pipe;
A hot water temperature sensor for detecting the temperature of hot water supplied from the hot water pipe;
Instantaneous heating type auxiliary heat source machine for heating hot water flowing through the hot water pipe,
A hot-water pipe that branches off from the hot water pipe on the downstream side of the heating spot by the auxiliary heat source unit and communicates with the bathtub;
A filling valve for opening and closing the filling pipe;
A hot water filling control unit that performs a hot water filling operation for opening the hot water filling valve and supplying hot water in the hot water storage tank to the bathtub through the hot water filling pipe according to a hot water filling start operation by a user; ,
Auxiliary heat source that activates the auxiliary heat source when the flow rate of hot water from the hot water storage tank to the tapping pipe is detected by the water amount sensor and the temperature detected by the tapping temperature sensor is lower than a predetermined target hot water supply temperature Machine control unit,
An assumed hot water start time setting unit for setting an assumed hot water start time, which is an assumed time at which the hot water operation on the day is started,
A first boiling operation for heating the hot water in the hot water storage tank is started by operating the tank circulation pump and the heat pump with a first capacity before a first predetermined time before the hot water filling start time. And when the hot water storage amount recognized by the hot water storage amount recognition unit falls below the first hot water storage amount during execution of the hot water filling operation by the hot water filling control unit, the tank circulation pump is operated. And a second boiling for heating the hot water in the hot water storage tank by operating the heat pump with a second capacity that has a higher heating amount and lower energy efficiency with respect to the hot water flowing through the tank circulation path than the first capacity. A hot water supply system comprising a boiling control unit for performing operation. The hot water supply system according to claim 1,
When the hot water filling control unit is performing the hot water filling operation by the hot water filling control unit, the hot water storage amount in the hot water storage tank recognized by the hot water storage amount recognition unit is less than or equal to the first hot water storage amount. The hot water supply system is characterized in that the second boiling operation is executed for a second predetermined time, and thereafter, the first boiling operation is switched to. The hot water supply system according to claim 1,
A hot water supply end expected time setting unit for setting a hot water supply end estimated time, which is an estimated time when use of hot water on the day ends,
The boiling control unit stops the heat pump until the next day after the boiling operation end time that is a third predetermined time before the estimated hot water supply end time, and the hot water filling operation by the hot water control unit performs the boiling operation. The second boiling operation is executed only when it is started before a time that is a fourth predetermined time before the operation end time, and the hot water filling operation by the hot water control unit is performed at the boiling operation end time. The hot water supply system is characterized by executing only the first boiling operation when started after a time before the fourth predetermined time. In the hot water supply system according to any one of claims 1 to 3,
A hot water supply start expected time setting unit for setting a hot water supply start estimated time, which is an assumed time at which use of hot water on the day is started,
The boiling control unit activates the tank circulation pump and activates the heat pump with a third capacity to heat the hot water in the hot water storage tank at a fifth predetermined time before the estimated hot water supply start time. When the third boiling operation is started and the flow of hot water from the hot water storage tank to the outlet pipe is detected by the water amount sensor during the execution of the third boiling operation, the tank circulation pump is operated. The heat pump is operated at a fourth capacity that has a larger heating amount for the hot water flowing through the tank circulation path than the third capacity, and is switched to a fourth boiling operation for heating the hot water in the hot water storage tank. Hot water supply system. The hot water supply system according to claim 4,
The boiling control unit detects the flow of hot water from the hot water storage tank to the hot water discharge pipe by the water amount sensor during the execution of the third boiling operation, and after switching to the fourth boiling operation, The hot water supply system, wherein when the amount of hot water stored in the hot water storage tank recognized by the hot water storage amount recognition unit becomes equal to or greater than the second hot water storage amount, the hot water supply system is returned to the third boiling operation. The hot water supply system according to claim 4,
The boiling control unit detects the flow of hot water from the hot water storage tank to the hot water discharge pipe by the water amount sensor during execution of the third boiling operation, and after switching to the fourth boiling operation, 6 A hot water supply system that returns to the third boiling operation when a predetermined time has elapsed. The hot water supply system according to any one of claims 4 to 6,
The boiling control unit is executing hot water from the hot water storage tank to the outlet pipe by the water amount sensor within the seventh predetermined time from the start of the third boiling operation during execution of the third boiling operation. The hot water storage tank is switched by the water amount sensor after the seventh predetermined time has elapsed since the start of the third boiling operation, only when the circulation of the water is detected. When the circulation of hot water from the hot water to the tap pipe is detected, the third boiling operation is continued without switching to the fourth boiling operation. The hot water supply system according to any one of claims 4 to 6,
The water amount sensor is in a state in which the boiling water control unit is executing the third boiling operation and the hot water storage amount in the hot water storage tank recognized by the hot water storage amount recognition unit is equal to or less than the third hot water storage amount. The hot water storage in the hot water storage tank recognized by the hot water storage amount recognition unit is switched to the fourth boiling operation only when the flow of hot water from the hot water storage tank to the hot water discharge pipe is detected by In a state where the amount is larger than the third hot water storage amount, when the water amount sensor detects the flow of hot water from the hot water storage tank to the hot water discharge pipe, without switching to the fourth boiling operation, A hot water supply system characterized by continuing the third boiling operation.