JP2011163659A - Hot water supply system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hot water supply system capable of suppressing heat release from hot water within a hot water storage tank while considering use of large amount of hot water by hot water filling to a bathtub, and of reducing energy consumption. <P>SOLUTION: The hot water supply system includes: the hot water storage tank 31 storing hot water heated by a heat pump 70; and a combustion water heater 10 heating hot water delivered from the hot water storage tank 31 by combustion of a burner 12. At start time of a first time zone set based on a time zone where hot water filling operation to the bathtub is performed, a tank controller 50 sets a first heating set temperature. After completion of the hot water filling operation within the first time zone and in a second time zone which is a time zone other than the first time zone, the tank controller 50 sets a second heating set temperature lower than the first heating set temperature. A heat pump controller 80 uses the heating set temperature as a target temperature and executes heating of the hot water storage tank 31 by the heat pump 70. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a hot water supply system in which an instantaneous heating type combustion water heater is connected in series downstream of a hot water storage tank for storing heated hot water.

  Conventionally, a hot water storage tank that stores hot water inside, a water supply pipe that supplies water into the hot water storage tank, a hot water discharge pipe that leads out hot water stored in the hot water storage tank, and hot water that is drawn from the hot water storage tank and heated to boil There is known a hot water supply system comprising a heat pump that returns hot water into a hot water storage tank, and an instantaneous combustion hot water heater that is connected in series downstream of the hot water storage tank and heats hot water flowing through the hot water discharge pipe by combustion of a burner. ing. The heat pump is very high in energy efficiency, but has a low heating capacity per unit time, and therefore cannot cope with sudden hot water supply. Therefore, a combustion water heater that operates when the hot water storage tank runs out is provided as an auxiliary heat source. Thereby, the hot water storage tank can be downsized.

  As such a hot water supply system, Patent Document 1 discloses that when hot water in a hot water storage tank is higher than a preset boiling start temperature, hot water is supplied from the hot water storage tank, and the hot water in the hot water storage tank is less than the predetermined temperature. In the case of, what supplies hot water using a combustion water heater is disclosed. When the hot water in the hot water storage tank becomes lower than the above temperature, the heat pump is operated to perform the operation of boiling up to the set temperature.

  Patent Document 2 discloses a hot water supply system that automatically heats a hot water storage tank by a heat pump at night because inexpensive nighttime power is used.

JP 2001-41570 A JP 2004-125226 A

  In the hot water supply system disclosed in Patent Document 1, the heat pump is operated every time the hot water in the hot water storage tank is below the boiling start temperature. However, this increases the number of times the heat pump is started and stopped, which increases energy consumption. In addition, hot water is always stored in the hot water storage tank, and energy loss increases due to heat dissipation from the hot water storage tank. Therefore, there is a problem that energy consumption increases as a whole.

  Moreover, in the hot water supply system disclosed in Patent Document 2, the heating operation by the heat pump is automatically performed at night. However, in the morning and in the daytime, it is rare that a large amount of hot water is needed due to the filling of the bathtub, etc. In the evening when a large amount of hot water is required, the hot water temperature in the hot water storage tank may be lowered due to heat dissipation loss. Therefore, there is a problem that energy consumption increases as a whole.

  In view of the above circumstances, the present invention is a hot water supply system comprising a hot water storage tank for storing hot water heated by a heat pump and a combustion hot water heater for heating hot water discharged from the hot water storage tank by combustion of a burner. It is an object of the present invention to provide a hot water supply system capable of reducing energy consumption by suppressing heat dissipation of hot water in a hot water storage tank while considering use of a large amount of hot water due to tension.

  The hot water supply system of the present invention includes a hot water storage tank, a hot water pipe connected to the upper part of the hot water storage tank for extracting hot water from the hot water storage tank, and a water supply system connected to the lower part of the hot water storage tank to supply water into the hot water storage tank. A hot water temperature detecting means for detecting the temperature of the hot water in the hot water storage tank, and an upstream end connected to the lower part of the hot water storage tank and a downstream end connected to the upper part of the hot water storage tank so that the hot water in the hot water storage tank A circulation pipe that circulates the hot water, a heat pump that heats the hot water in the hot water storage tank via the circulation pipe, and a combustion water heater that is provided in the hot water discharge pipe and heats the hot water flowing through the hot water discharge pipe by combustion of a burner And a hot water pipe that connects the hot water pipe and the bathtub to supply hot water to the bathtub, and a boiling point that sets a boiling set temperature as a target temperature when the heat pump boils hot water in the hot water storage tank. When the detected temperature of the boiling temperature setting means and the hot water storage temperature detection means is lower than the boiling start temperature set in advance, the boiling temperature set by the boiling temperature setting means is set as the target temperature, and the hot water storage Tank boiling control means for performing boiling of hot water in the hot water storage tank by the heat pump so that the hot water in the tank reaches a target temperature, and the boiling temperature setting means includes the hot water in one day. When the start time of the first time zone set based on the time zone in which the hot water filling operation to the bathtub is performed via the tension tube, the first boiling set temperature is set in the heat pump, After the hot water filling operation is performed in the first time zone and in the second time zone that is a time zone other than the first time zone, the first heating device is installed in the heat pump. And sets the second water heating set temperature a temperature lower than the temperature.

  In the hot water supply system of the present invention configured as described above, when the boiling temperature setting means reaches the start time of the first time zone, the first boiling setting temperature (for example, 60 ° C.) is set in the heat pump. . Thereby, when the temperature detected by the hot water storage temperature detecting means becomes lower than a preset boiling start temperature (for example, 35 ° C.) in the first time zone, the tank boiling control means sets the first boiling setting. Using the temperature (for example, 60 ° C.) as the target temperature, boiling of the hot water in the hot water storage tank is executed by the heat pump so that the hot water in the hot water storage tank becomes the target temperature.

  The first time zone is set based on a time zone in which a hot water filling operation to the bathtub is performed through the hot water filling tube in one day. That is, the first time zone is a time zone (for example, 14 hours) that combines a time zone in which there is a high possibility of filling the bathtub and a time required for boiling by the heat pump to be performed before this time zone. : 00 to 19:00). By doing so, there is a high possibility that a large amount of hot water for filling the bathtub can be supplied from the hot water storage tank.

  Then, after the hot water filling is performed in the first time zone, and in the second time zone that is a time zone other than the first time zone, the heat pump is supplied with a second boiling set temperature ( For example, 45 ° C.) is set. When hot water filling is performed at any time within the first time zone, the hot water in the hot water storage tank boiled with the first boiling set temperature (for example, 60 ° C.) as the target temperature may be supplied to the bathtub. Therefore, the hot water used for filling is unnecessary after filling. Therefore, for the remaining time in the first time zone after the hot water filling is performed, the boiling temperature setting means sets a second boiling setting temperature (for example, 45 ° C.), during which the hot water storage temperature is set. Even if the detection temperature of the detection means becomes lower than the boiling start temperature (for example, 35 ° C.), the tank boiling control means sets the second boiling setting temperature (for example, 45 ° C.) lower than the first boiling setting temperature. Boil up to the target temperature. As a result, it is possible to avoid a state in which hot water is unnecessarily stored in the hot water storage tank in a state where it is not used in large quantities after hot water filling, and heat dissipation loss of the hot water storage tank can be suppressed.

  And even in the second time zone, the possibility of filling the bathtub with water is extremely low, so the boiling temperature setting means sets the second boiling setting temperature (for example, 45 ° C.), During this time, if the detected temperature of the hot water storage temperature detecting means becomes lower than the boiling start temperature (for example, 35 ° C.), the tank boiling control means is heated to the second boiling set temperature (for example, 45 ° C.) as the target temperature. Execute.

  As described above, a relatively large amount of hot water is supplied from the hot water storage tank only during the time when the bath is filled, and comparison is made after the bath is filled and when the bath is not filled. Since hot water of low temperature can be stored in the hot water storage tank, the hot water in the hot water storage tank can be boiled and stored according to the hot water supply situation, and energy consumption can be drastically reduced.

  In the hot water supply system of the present invention, the hot water storage temperature detecting means includes a first hot water temperature sensor for detecting a temperature of hot water in an upper layer portion in the hot water storage tank, and a temperature of the hot water below the first hot water storage temperature sensor. And the tank boiling control means detects the tank hot water control means when the temperature detected by the first hot water storage temperature sensor becomes lower than the boiling start temperature in the second time zone. When the temperature detected by the second hot water storage temperature sensor becomes lower than the boiling start temperature, the boiling by the heat pump is started when the boiling by the heat pump is started and at least the hot water filling operation is performed in the first time zone. It is characterized by starting the raising.

  In the present invention, the hot water discharge pipe is connected to the upper part of the hot water storage tank, and the water supply pipe is connected to the lower part of the hot water storage tank. Therefore, when hot water is supplied from the hot water storage tank to the hot water discharge pipe, water is supplied from the water supply pipe to the lower part of the hot water storage tank accordingly. In the hot water storage tank, a hot water layer is formed at the top and a water layer is formed at the bottom. As hot water is supplied from the hot water storage tank, the upper hot water layer decreases, and when the upper layer portion of the hot water storage tank becomes a water layer, the hot water runs out. And since the said 1st hot water storage temperature sensor detects the temperature of the hot water of the upper layer site | part in a hot water storage tank, when this detection temperature becomes less than the said boiling start temperature, a hot water runout state can be grasped | ascertained.

  According to the present invention, in the second time zone, when the temperature detected by the first hot water storage temperature sensor becomes lower than the boiling start temperature, the tank boiling control means starts boiling. The hot water in the hot water storage tank can be boiled at the timing when the hot water runs out in the tank. Then, from the start time of the first time zone to the time when the hot water filling operation is started, the temperature at which boiling is started is detected by a second hot water storage temperature sensor provided below the first hot water storage temperature sensor. Therefore, the hot water in the hot water storage tank can be boiled up at an earlier timing than when the hot water tank runs out. Thereby, in the 1st time slot | zone, the comparatively high temperature hot water by 1st boiling preset temperature (for example, 60 degreeC) can be stored in the hot water storage tank at an early stage before the hot water filling to a bathtub. .

  Further, at this time, the boiling temperature setting means sets the second boiling setting temperature to the heat pump during the filling operation within the first time zone, and the tank boiling control means When the temperature detected by the second hot water storage temperature sensor becomes lower than the boiling start temperature during the filling operation within the first time zone, the heating by the heat pump is started.

  A large amount of hot water from the hot water storage tank is used for filling the bathtub. For this reason, it can be assumed that the hot water in the hot water storage tank runs out at a relatively early time, and water is supplied from the water supply pipe to the hot water storage tank. Therefore, during the filling of the hot water in the first time zone, the temperature of the second hot water storage temperature sensor is used to quickly set the second boiling set temperature without waiting for the hot water storage tank to run out. Boiling at the target temperature can be started. After hot water filling, hot water is not necessary, and the hot water storage tank is heated efficiently with the second boiling set temperature. Thereby, the opportunity to heat with a combustion hot water heater can be reduced, and furthermore, the heat consumption loss can be prevented by making the temperature of the hot water in the hot water storage tank relatively low by the second boiling preset temperature, so that energy consumption can be suppressed.

  In addition to starting boiling using the second hot water storage temperature sensor or the circulating upstream temperature sensor, the boiling temperature setting means is configured to perform the hot water filling operation during the first time zone. The second boiling preset temperature may be set in a heat pump, and the tank boiling control means may start boiling by the heat pump at the start of the hot water filling operation within the first time zone. .

  When hot water filling to the bathtub is started, it can be assumed that the hot water in the hot water storage tank will eventually run out. Accordingly, if the heating by the heat pump is started at the time when the hot water filling operation is started within the first time zone, the boiling can be started without waiting for the hot water tank to run out, Since the relatively low temperature hot water can be stored in the hot water storage tank by the second boiling preset temperature, it is possible to suppress heat dissipation loss and to suppress excessive energy consumption.

The block diagram of the hot-water supply system in embodiment of this invention. The flowchart which shows the action | operation of the hot-water supply system shown in FIG. The flowchart which shows the action | operation of the hot-water supply system shown in FIG.

  Embodiments of the present invention will be described with reference to the drawings. With reference to FIG. 1, the hot water supply system of the present embodiment is configured by an instantaneous heating combustion water heater 10, a tank unit 30, and a heat pump unit 60.

  The heat pump unit 60 includes a heat pump 70 configured by connecting a compressor 71, a condenser 72, a decompressor 73, and an evaporator 74 through a refrigerant circulation path 75. The condenser 72 is connected to a tank circulation path 64 (circulation pipe) connected to the upper and lower parts of the hot water storage tank 31 to exchange heat between the refrigerant in the refrigerant circulation path 75 and the hot water in the tank circulation path 64. Thus, the hot water in the tank circulation path 64 is heated.

  The tank circulation path 64 includes a circulation pump 65 for circulating the hot water stored in the hot water storage tank 31 into the tank circulation path 64, and a forward thermistor for detecting the temperature of the hot water supplied from the condenser 72 to the hot water storage tank 31. 66 and a return thermistor 41 (circulation upstream temperature sensor) for detecting the temperature of hot water supplied from the hot water storage tank 31 to the condenser 72 are provided.

  Then, a temperature detection signal from the forward thermistor 66 is input to the heat pump controller 80 constituted by a microcomputer or the like. Further, the operation of the heat pump 70 and the circulation pump 65 is controlled by a control signal output from the heat pump controller 80.

  The heat pump controller 80 is communicably connected to the tank controller 50 and functionally includes tank boiling control means for controlling the heat pump 70 when boiling hot water in the hot water storage tank 31 is performed. The tank controller 50 functionally includes a boiling temperature setting means for setting a boiling setting temperature as a boiling target temperature when the tank boiling control means uses the heat pump 70 to boil hot water in the hot water storage tank 31. A boiling instruction signal including the boiling preset temperature is transmitted to the heat pump controller 80.

  When the heat pump controller 80 receives the boiling instruction signal from the tank controller 50, the heat pump controller 80 uses the boiling set temperature and the detected temperature of the return thermistor 41 so that the detected temperature of the forward thermistor 66 becomes the boiling set temperature. 70 is operated to boil hot water in the hot water storage tank 31. In the present embodiment, the boiling temperature setting means of the tank controller 50 selectively selects 60 ° C. (first boiling setting temperature) and 45 ° C. (second boiling setting temperature) as the boiling setting temperature. Used for.

  Next, the tank unit 30 includes a hot water storage tank 31, a hot water pipe 2 connected to the upper part of the hot water storage tank 31, a lower part of the hot water storage tank 31 and a water supply pipe 1 connected to the hot water pipe 2, and the combustion hot water heater 10. A hot water bypass pipe 37 that bypasses and communicates the hot water discharge pipe 2 on the upstream side and the downstream side of the combustion water heater 10 is provided. At the outlet of the hot water pipe 2 to which the end of the hot water bypass pipe 37 is connected, there is provided a hot water tap 3 (curan in the drawing) such as a currant or shower.

  Furthermore, the tank unit 30 detects the temperature of the hot water storage thermistor 32 (first hot water storage temperature sensor) that detects the temperature of hot water in the upper layer as the hot water detection position of the hot water storage tank 31 and the temperature of the hot water at a position below the hot water storage thermistor 32. The incoming water flow rate for detecting the water flow rate of the hot water supply thermistor 33 provided in the vicinity of the upstream side of the connection point X between the intermediate thermistor 42 (second hot water storage temperature sensor) and the hot water supply pipe 1 of the hot water supply pipe 2. A sensor 43, a tank flow rate sensor 46 for detecting the flow rate of hot water discharged from the hot water storage tank 31 to the hot water discharge pipe 2, an incoming water thermistor 44 provided in the water supply pipe 1, and the hot water storage tank 31 are supplied to the hot water discharge pipe 2. A hot water variable valve 34 for changing the flow rate of hot water, a water variable valve 35 for changing the flow rate of water supplied from the water supply pipe 1 to the hot water discharge pipe 2, and a pressure reducing valve with a check valve provided in the water supply pipe 1 0, a mixed thermistor 36 provided between the connection point X of the hot water pipe 2 and the water supply pipe 1 and the hot water bypass pipe 37, a bypass valve 38 for opening and closing the hot water bypass pipe 37, the hot water bypass pipe 37 and the hot water A hot water supply outlet thermistor 39 that detects the temperature of hot water supplied to the downstream side of the connection point Y with the pipe 2 is provided. The hot water storage thermistor 32 and the intermediate thermistor 42 constitute hot water storage temperature detection means in the present invention.

  A temperature detection signal from the hot water storage thermistor 32, the hot water thermistor 33, the hot water thermistor 44, the mixed thermistor 36, the hot water supply thermistor 39, and the return thermistor 41, the incoming water flow rate sensor 43, and the tank The detection signal of the water flow rate by the flow sensor 46 is input. The operation of the hot water variable valve 34, the water variable valve 35, and the bypass valve 38 is controlled by a control signal output from the tank controller 50.

  Further, the tank controller 50 monitors the detected temperature of the hot water storage thermistor 32 or the intermediate thermistor 42, and when the detected temperature becomes lower than a preset boiling start temperature (35 ° C.), The above boiling instruction signal is transmitted. Then, with the boiling set temperature (60 ° C. or 45 ° C.) set by the boiling temperature setting means of the tank controller 50 as the boiling target temperature, the tank boiling control means of the heat pump controller 80 causes the hot water in the hot water storage tank 31 to flow. The boiling operation is performed to reach the boiling target temperature.

  Furthermore, although not shown, the tank controller 50 functionally includes a clock unit that outputs the current time, and a time zone setting unit that sets one day as a plurality of time zones according to the time output by the clock unit. ing. Thereby, the tank controller 50 classifies 14: 0 to 19:00 as the first time zone, and classifies the other time zones as the second time zone. In addition, 14: 00 to 19:00, which is the first time zone, includes a bathing time in a general home, and further, a time required for filling a bathtub with water before the bathing time, In addition, the time required for boiling the hot water in the hot water storage tank 31 is set. In the present embodiment, the first time zone is set to 14:00 to 19:00. However, if the above time is taken into consideration, an appropriate time zone can be set as the first time zone. it can.

  And the tank controller 50 sets the boiling preset temperature according to said time slot | zone, and the heat pump controller 80 performs a boiling operation according to hot water filling. The boiling operation according to this embodiment will be described in detail later.

  In addition, the tank controller 50 has a desired hot water supply temperature (temperature of hot water supplied from the outlet of the hot water outlet pipe 2) and bath temperature (via a hot water pipe 18 described later) in the bathtub according to the user's operation. A temperature switch (not shown) for setting the temperature of hot water to be supplied), a general hot water supply mode (a mode in which hot water filling valve 19 to be described later is closed and hot water is supplied from the outlet of hot water outlet pipe 2), hot water A remote controller 51 having a mode changeover switch (not shown) and the like for switching the tension mode (mode in which the hot water valve 19 is opened and hot water is supplied from the hot water pipe 18 to the bathtub) is connected.

  Here, the hot water discharge pipe 2 is connected to the upper part of the hot water storage tank 31, and the water supply pipe 1 is connected to the lower part of the hot water storage tank 31. Therefore, when hot water is supplied from the hot water storage tank 31 to the hot water discharge pipe 2, water is supplied from the water supply pipe 1 to the lower part of the hot water storage tank 31 accordingly. In the hot water storage tank 31, a hot water layer is formed at the top and a water layer is formed at the bottom. As hot water is supplied from the hot water storage tank 31, the upper hot water layer decreases, and when the upper layer portion of the hot water storage tank 31 becomes a water layer, the hot water runs out. The tank controller 50 determines that the hot water storage tank 31 is out of hot water when the temperature detected by the hot water storage thermistor 32 is lower than a preset boiling start temperature.

  In the tank controller 50, when water flow exceeding a predetermined lower limit flow rate is detected by the incoming water flow rate sensor 43 without running out of hot water, the detected temperature of the mixed thermistor 36 or the hot water supply outlet thermistor 39 becomes the target temperature. Thus, the mixed temperature control for controlling the opening degree of the hot water variable valve 34 and the water variable valve 35 is performed. At this time, the tank controller 50 opens the bypass valve 38 in the general hot water supply mode, and closes the bypass valve 38 in the hot water filling mode.

  On the other hand, when water flow exceeding the lower limit water amount is detected by the incoming water flow rate sensor 43 in the state where the hot water is running out, the tank controller 50 closes the bypass valve 38 and the hot water storage tank 31 and the water supply pipe 1. All hot water from is supplied to the combustion water heater 10. In this case, in the combustion water heater 10, heating temperature adjustment control is performed by a hot water controller 20 described later.

  Next, the combustion water heater 10 heat-exchanges the tapping pipe 2 by bypassing the heat exchanger 11 provided in the middle of the tapping pipe 2, the burner 12 that heats the heat exchanger 11, and the heat exchanger 11. A hot water supply bypass pipe 13 communicating between the upstream side and the downstream side of the vessel 11, and a hot water filling pipe 18 connecting a bathtub (not shown) and the hot water supply pipe 2 on the downstream side of the connection point Z between the hot water supply pipe 2 and the hot water supply bypass pipe 13. And.

  The hot water supply pipe 2 is supplied to a bypass servo 14 that changes a distribution ratio between the flow rate of hot water supplied to the heat exchanger 11 side and the flow rate of hot water supplied to the hot water supply bypass pipe 13 side, and the combustion hot water supply 10. A water volume servo 15 for adjusting the flow rate of hot water, a hot water flow rate sensor 21 for detecting the flow rate of hot water supplied to the heat exchanger 11 and the hot water supply bypass pipe 13, and a connection point Z between the hot water discharge pipe 2 and the hot water supply bypass pipe 13. A hot water heater thermistor 16 for detecting the temperature of the hot water supplied to the downstream side of the gas and a check valve 17 are provided. The hot water filling pipe 18 is provided with a hot water filling flow rate sensor 22 for detecting the flow rate of the hot water filling pipe 18 and a hot water filling valve 19 for opening and closing the hot water filling pipe 18.

  A temperature detection signal from the water heater thermistor 16, a water flow rate detection signal from the water heater flow sensor 21, and a water flow rate detection signal from the hot water flow rate sensor 22 are supplied to the hot water controller 20 constituted by a microcomputer or the like. Are entered. Further, the operation of the bypass servo 14, the water amount servo 15, the burner 12, and the hot water filling valve 19 is controlled by a control signal output from the hot water supply controller 20.

  The hot water supply controller 20 is communicably connected to the tank controller 50 and enters a heating permission state when receiving a signal for instructing heating from the tank controller 50. The heating temperature for controlling the combustion amount of the burner 12 so that the detected temperature of the hot water heater thermistor 16 becomes the target hot water temperature when water flow of a predetermined lower limit flow rate is detected by the hot water heater flow rate sensor 21. Execute adjustment control. Further, when a signal for instructing heating is received from the tank controller 50, the heating is prohibited and execution of the heating temperature control is prohibited.

  In addition, the hot water supply controller 20 opens the hot water filling valve 19 when the hot water filling operation for supplying a predetermined amount of hot water to a bathtub (not shown) (hot water filling mode) is performed by the hot water filling flow rate sensor 22. Accumulate the amount of hot water supplied to the detected bathtub. When the cumulative amount of hot water supplied to the bathtub reaches the predetermined amount, the hot water filling valve 19 is closed to end the hot water filling operation. Then, the hot water supply controller 20 transmits a hot water filling operation signal indicating the start and end of the hot water filling operation to the tank controller 50, and the tank controller 50 responds to the hot water filling operation signal to the heat pump controller 80. Send boiling instructions.

  Next, the hot water boiling operation of the hot water storage tank 31 by the hot water supply system of this embodiment will be described in detail with reference to the flowcharts of FIGS.

  Referring to FIG. 2, tank controller 50 first stops the operation of heat pump 70 via heat pump controller 80 in STEP 1, and sets the boiling set temperature in heat pump 70 to 45 ° C. for heat pump controller 80 in STEP 2. To do. In the next STEP 3, the heat pump controller 80 determines whether or not the hot water filling operation is being performed through communication with the hot water supply controller 20. If not, the process proceeds to STEP 4. Proceed to STEP 11.

  When proceeding to STEP 4 in FIG. 2, the tank controller 50 determines whether or not the current time output by the clock unit is 14:00 (that is, the start time of the first time zone), and at 14:00. If there is, proceed to STEP5, and if not 14:00, proceed to STEP14 of FIG.

  Steps 5 to 10 in FIG. 2 are operations in the first time zone. When proceeding to STEP 5, the tank controller 50 sets the boiling set temperature in the heat pump 70 to 60 ° C. with respect to the heat pump controller 80, and proceeds to STEP 6.

  In STEP 6, the tank controller 50 proceeds to STEP 7 if the current time is from 14:00 to 19:00 (within the first time zone), and returns to STEP 2 if the current time exceeds 19:00.

  In STEP 7, the tank controller 50 determines whether or not a hot water filling operation is performed at 14:00 to 19:00 (within the first time zone), and the hot water filling operation is performed even once between 14:00:00 and 19:00. If it has been performed (or is being filled), the process returns to STEP 2, and if the filling operation has not been performed once (or is not being filled), the process proceeds to STEP 8.

  When proceeding to STEP 8, if the detected temperature of the intermediate thermistor 42 is not less than 35 ° C. (less than the boiling start temperature), the determination of STEP 6 and STEP 7 is repeated, and the current time is 14:00 to 19:00 (first 1), and when the temperature of the intermediate thermistor 42 is less than 35 ° C., the heat pump 70 boils through the heat pump controller 80 in STEP 9. Instruct the lifting operation.

  In STEP 9, since the boiling set temperature is set to 60 ° C. in STEP 5, the heat pump 70 performs the boiling water heating operation of the hot water storage tank 31 with the boiling target temperature set to 60 ° C. Then, in STEP 10, the heat pump controller 80 continues the boiling operation by the heat pump 70 until the return thermistor 41 of the tank circulation path 64 becomes 40 ° C. or higher.

  When hot water is supplied from the tank circulation path 64 to the upper part of the hot water storage tank 31, water below 35 ° C. returns from the lower part of the hot water storage tank 31 to the tank circulation path 64 accordingly. And in the hot water storage tank 31, a hot water layer increases from the upper part to the lower part. At this time, the high temperature hot water layer and the low temperature hot water layer are mixed in a relatively narrow range, and when the mixed hot water layer reaches the vicinity of the lower part of the hot water storage tank 31, the tank circulates from the lower part of the hot water storage tank 31. The temperature of hot water entering the upstream side of the path 64 rises. From this, the heat pump controller 80 considers that a sufficient amount of hot water has accumulated in the hot water storage tank 31 when the detected temperature of the return thermistor 41 rises (when it reaches 40 ° C. or higher). . Then, when the return thermistor 41 reaches 40 ° C. or higher in STEP 10, the process returns to STEP 1 to stop the heat pump 70.

  As described above, when the hot water filling operation is not performed in STEP 7 within the first time zone in STEP 6, the start of the heating operation of the heat pump 70 in STEP 9 is determined based on the detected temperature of the intermediate thermistor 42 in STEP 8. In anticipation that a large amount of hot water in the hot water storage tank 31 is consumed in the hot water filling operation, the hot water storage tank 31 can be filled with hot water (60 ° C.) at an early stage. And by storing a large amount of hot water for use in the hot water filling operation in the hot water storage tank 31 at an early stage, the hot water storage tank 31 can be prevented from running out during the hot water filling operation, and the combustion water heater 10 can be heated. It is possible to eliminate or reduce the energy consumption.

  Further, when the filling operation is started in STEP 7, the filling operation is performed within the first time zone, so that the process proceeds to STEP 11 in FIG. 3 through STEP 2 and STEP 3. When the detected temperature of the intermediate thermistor 42 becomes less than 35 ° C. (less than the boiling start temperature) in STEP 11, the process proceeds to STEP 12.

  In STEP 12, since the boiling set temperature is set to 45 ° C. in STEP 2, the heat pump 70 performs the boiling operation of the hot water in the hot water storage tank 31 with 45 ° C. being the boiling target temperature.

  Then, in STEP 13, the heat pump controller 80 continues the heating operation by the heat pump 70 until the return thermistor 41 of the tank circulation path 64 becomes 40 ° C. or higher. When the return thermistor 41 becomes 40 ° C. or higher, the heat pump controller 80 returns to STEP 1 in FIG. 70 is stopped. Thereby, when the hot water filling operation is being performed, hot water of 60 ° C. stored in the hot water storage tank 31 is supplied, but hot water having a relatively high temperature of 60 ° C. is not supplied from the hot water tap 3 after the hot water filling operation. Since it is unnecessary, 45 ° C. hot water suitable for hot water supply from the hot water tap 3 can be stored in the hot water storage tank 31, and heat dissipation loss of the hot water storage tank 31 can be prevented.

  Further, when the hot water is not filled in STEP 3 in FIG. 2 and the current time is not 14:00 in STEP 4, the process proceeds to STEP 14 in FIG. When proceeding to STEP 14, if it is the first time zone in STEP 7 of FIG. 2 after hot water filling has been performed, or if the current time is a time zone other than 14:00 to 19:00 (second time zone) Obi). Then, in STEP 14 of FIG. 3, when the temperature detected by the hot water storage thermistor 32 is less than 35 ° C. (out of hot water), the tank controller 50 proceeds to STEP 12 and is heated by the heat pump 70 via the heat pump controller 80. Instruct the operation.

  Then, in the next STEP 13, the heat pump controller 80 continues the heating operation by the heat pump 70 until the return thermistor 41 of the tank circulation path 64 becomes 40 ° C. or higher, and returns to STEP 1 in FIG. 2 when the return thermistor 41 becomes 40 ° C. or higher. The heat pump 70 is stopped.

  Also at this time, since the boiling setting temperature is set to 45 ° C. in STEP 2 of FIG. 2, the heat pump 70 performs the boiling operation of the hot water in the hot water storage tank 31 with 45 ° C. being the boiling target temperature. Therefore, when it is the first time zone but after hot water filling is performed, or when it is a time zone (second time zone) other than 14:00 to 19:00 (first time zone) Therefore, hot water at a relatively high temperature of 60 ° C. is not required, so that hot water at 45 ° C. suitable for hot water supply from the tap tap 3 can be stored in the hot water storage tank 31, and heat dissipation loss of the hot water storage tank 31 can be prevented. .

  In the present embodiment, by providing the route of STEP7-STEP2-STEP3-STEP11-STEP12 in FIG. 2, the start of boiling operation during filling is determined using the detected temperature of the intermediate thermistor 42. In addition, although not shown, when the tank controller 50 receives a signal indicating the start of the hot water filling operation from the hot water supply controller 20 during the first time zone, the heat pump 70 raises 45 ° C. to the target temperature. The hot water boiling operation of the hot water storage tank 31 may be performed. When the hot water filling operation is started, there is a very high possibility that the hot water storage tank 31 will eventually run out of hot water. Therefore, when the hot water filling operation is started, the hot water boiling operation of the hot water storage tank 31 is started, so that the hot water storage tank 31 can be reliably prevented from running out immediately after the hot water filling is completed. Even if hot water is supplied from the plug 3, the operation of the combustion water heater 10 can be avoided and energy consumption can be suppressed.

  DESCRIPTION OF SYMBOLS 1 ... Water supply pipe, 2 ... Hot water pipe, 10 ... Combustion water heater, 18 ... Hot water filling pipe, 31 ... Hot water storage tank, 32 ... 1st hot water storage temperature sensor (hot water storage thermistor), 42 ... 2nd hot water storage temperature sensor (intermediate thermistor) 50 ... tank controller (boiling temperature setting means), 64 ... tank circulation path (circulation pipe), 70 ... heat pump, 80 ... heat pump controller (tank boiling control means).

Claims (4)

A hot water storage tank,
A hot water outlet pipe connected to the upper part of the hot water storage tank to draw hot water from the hot water storage tank;
A water supply pipe connected to the lower part of the hot water storage tank to supply water into the hot water storage tank;
Hot water storage temperature detecting means for detecting the temperature of hot water in the hot water storage tank;
A circulation pipe that circulates hot water in the hot water storage tank with an upstream end connected to the lower part of the hot water storage tank and a downstream end connected to the upper part of the hot water storage tank;
A heat pump for heating hot water in the hot water storage tank through the circulation pipe;
A combustion water heater that is interposed in the tapping pipe and heats hot water flowing through the tapping pipe by combustion of a burner;
A hot water pipe connecting the outlet pipe and the bathtub and supplying hot water to the bathtub;
A boiling temperature setting means for setting a boiling setting temperature to be a target temperature when the heat pump boils hot water in the hot water storage tank;
When the detected temperature of the hot water storage temperature detecting means is lower than a preset boiling start temperature, the hot water in the hot water storage tank is set as a target temperature using the boiling temperature set by the boiling temperature setting means as a target temperature. Tank boiling control means for performing boiling of hot water in the hot water storage tank by the heat pump so as to be at a temperature,
When the boiling temperature setting means has reached the start time of the first time zone set based on the time zone in which the hot water filling operation to the bathtub is performed through the hot water filling pipe in one day, After the first boiling preset temperature is set in the heat pump and the hot water filling operation is performed within the first time zone, and after the second time zone which is a time zone other than the first time zone In the hot water supply system, a second boiling preset temperature lower than the first boiling preset temperature is set in the heat pump. The hot water storage temperature detection means includes a first hot water storage temperature sensor that detects the temperature of hot water in an upper layer in the hot water storage tank, and a second hot water storage temperature sensor that detects the temperature of hot water below the first hot water storage temperature sensor. With
The tank boiling control means starts boiling by the heat pump when the temperature detected by the first hot water storage temperature sensor is lower than the boiling start temperature in the second time period, The boiling by the heat pump is started when the temperature detected by the second hot water storage temperature sensor becomes lower than the boiling start temperature at least until the hot water filling operation is performed in a time zone. The hot water supply system described. The boiling temperature setting means sets the second boiling temperature setting in the heat pump during the hot water filling operation in the first time zone,
The tank boiling control means starts boiling by the heat pump when the temperature detected by the second hot water storage temperature sensor becomes lower than the boiling start temperature during the filling operation within the first time zone. The hot water supply system according to claim 2. The boiling temperature setting means sets the second boiling temperature setting in the heat pump during the hot water filling operation in the first time zone,
The hot water supply system according to claim 1, wherein the tank boiling control means starts boiling by the heat pump at the start of the hot water filling operation within the first time zone.

Images