JP4064332B2 - Hot water storage water heater - Google Patents

Description

  The present invention relates to a hot water storage type hot water supply apparatus that uses hot water stored in a hot water storage tank to replenish hot water in a bathtub.

Conventionally, in this type of electric water heater and heat pump hot water storage type hot water supply device, it is possible to recharge hot water in the bathtub using the hot water stored in the hot water storage tank, and if there is a reheating instruction, the temperature of the hot water stored in the hot water storage tank If this temperature is equal to or higher than the predetermined temperature T1, the bath circulating pump is driven to circulate the bath water to the heat exchanger and perform a reheating operation by exchanging heat with the hot water in the hot water storage tank. When the temperature of the hot water storage tank dropped to a temperature that was insufficient for reheating during operation, the reheating operation was stopped.
JP 2003-50048 A

  However, in this conventional system, even if the amount of stored hot water at the start of reheating is small, the reheating operation is performed if the stored hot water temperature is equal to or higher than the predetermined temperature T1, and therefore the amount of heat in the hot water storage tank is changed during the reheating operation. Even if the amount of heat drops to a level that is insufficient for reheating, the reheating operation is continued and it takes a long time to raise the bath water to the user's desired temperature. There was a case that the convenience of was impaired.

  Accordingly, in order to solve the above-described problems, the present invention provides a hot water storage tank for storing hot water, a plurality of hot water temperature sensors for detecting the hot water temperature of the hot water storage tank, and a bath circulation pump provided with hot water in the bathtub. A bath circulation circuit that circulates, and a heat exchanger that is provided in the hot water storage tank and is heated in the hot water storage tank and that heats the bathtub water with hot water stored in the hot water storage tank, and drives the bath circulation pump. In a hot water storage type hot water supply apparatus in which bath water is circulated through the heat exchanger for reheating, the amount of stored hot water Q1 and the heat that can contribute to reheating with a plurality of hot water temperatures detected by the plurality of hot water temperature sensors The amount of stored hot water Q2 in the vicinity of the exchanger is calculated, the amount of stored hot water Q1 that can contribute to reheating is equal to or greater than the predetermined amount of heat Q3, and the amount of stored hot water Q2 near the heat exchanger is equal to or greater than the predetermined amount of heat Q4. That the conditions were allowed to start the reheating operation.

  Further, in claim 2, a hot water storage tank for storing hot water, a plurality of hot water temperature sensors for detecting a hot water storage temperature of the hot water storage tank, a bath circulation circuit having a bath circulation pump for circulating hot water in the bathtub, and the bath circulation A heat exchanger provided in the hot water storage tank for heating the bath water with hot water stored in the hot water storage tank, and driving the bath circulation pump to circulate the bath water to the heat exchanger. In the hot water storage type hot water supply apparatus configured to reheat, the stored hot water amount Q1 that can contribute to reheating is calculated by the plurality of hot water temperatures detected by the plurality of hot water temperature sensors, and the stored heat amount Q1 that can contribute to reheating. The reheating operation can be started on the condition that the heat quantity is equal to or higher than the predetermined heat quantity Q3 and the hot water storage temperature near the heat exchanger is equal to or higher than T1.

  According to the present invention, the start condition of the reheating operation is determined in consideration of not only the heat amount or temperature in the vicinity of the heat exchanger in the hot water storage tank but also the hot water storage amount that can contribute to the reheating in the hot water storage tank. Therefore, it is possible to more accurately determine whether or not the driving operation can be performed, and the convenience for the user can be greatly improved.

  Next, an embodiment of the present invention will be described with reference to the drawings.

  This hot water storage type hot water supply device boils and stores hot water in the midnight hours when the unit price of contracted power by time is low, and uses the hot water stored for hot water supply. 1 is a hot water storage tank 2 for storing hot water. 3 is a heat pump unit as a heating means for heating hot water in the hot water storage tank, 4 is a hot water tap provided in a kitchen or a washroom, etc. 5 is a remote control for remotely operating the hot water storage type hot water supply device , 6 is a bathtub.

  The hot water storage tank 2 of the hot water storage tank unit 1 has a hot water discharge pipe 7 connected to the upper end, a water supply pipe 8 connected to the lower end, a heat pump forward pipe 9 constituting a heat pump circulation circuit in the lower part, and a heat pump circulation circuit in the upper part. The heat pump return pipe 10 is connected, the hot water in the hot water storage tank 2 taken out from the heat pump forward pipe 9 is boiled by the heat pump unit 3 and returned to the hot water storage tank 2 from the heat pump return pipe 10 to be stored in the hot water supply pipe. The hot water in the hot water storage tank 2 is pushed up by the water supply from 8, and the hot water in the upper part of the hot water storage tank 2 is pushed out from the hot water discharge pipe 7 to supply hot water.

  The heat pump unit 3 includes a compressor 11, a refrigerant-water heat exchanger 12 as a condenser, an electronic expansion valve 13, a forced air-cooled evaporator 14, and hot water in the hot water storage tank 2. A heat pump circulation pump 16 that circulates to the refrigerant-water heat exchanger 12 through the heat pump forward pipe 9 and the heat pump return pipe 10 and a heat pump control unit 17 that controls driving thereof are provided in the heat pump circuit 15. Is one in which carbon dioxide is used as a refrigerant to constitute a supercritical heat pump cycle. Since carbon dioxide is used as the refrigerant, low-temperature water can be boiled up to a high temperature of about 90 ° C. without an electric heater.

  Here, the refrigerant-water heat exchanger 12 employs a counter flow system in which the refrigerant and hot water in the hot water storage tank 2 that is heated water are opposed to each other. In the supercritical heat pump cycle, the refrigerant is exchanged during heat exchange. Since it is condensed in the supercritical state, the heated water can be efficiently heated to a high temperature so that the temperature difference between the refrigerant-water heat exchanger 12 inlet temperature and the refrigerant outlet temperature is constant. Further, by controlling the electronic expansion valve 12 or the compressor 11, the water to be heated can be heated in a state where the COP (energy consumption efficiency) is very good.

  Next, 18 is a heat exchanger made of a stainless steel serpentine tube for heating the hot water in the bathtub 6, and is arranged at the upper part in the hot water storage tank 2. A bath circulation circuit 22 comprising a bath return pipe 21 provided with a bath circulation pump 20 is connected so that hot water in the bathtub 6 can be circulated, and the hot water in the bathtub 6 is heated by the high-temperature water in the hot water storage tank 2 for heat insulation. Or it is something that is chased.

  23 is a bath return temperature sensor that detects the temperature of the bath water flowing into the heat exchanger 18 through the bath return pipe 21, and 24 is a bath that flows out of the heat exchanger 18 and flows into the bath 6 through the bath pipe 19. A temperature sensor that detects the temperature of water.

  Next, 25 is a hot water mixing valve composed of an electric mixing valve that mixes hot water from the hot water discharge pipe 7 and low temperature water from the water supply bypass pipe 26 branched from the water supply pipe 9. The mixing ratio is controlled so that the hot water temperature detected by the provided hot water temperature sensor 28 becomes the hot water supply set temperature set by the user using the remote controller 5.

  Reference numeral 29 denotes a hot water filling pipe branched from the hot water supply pipe 27 and communicated with the bath return pipe 21. The hot water filling pipe 29 includes a hot water filling valve 30 for starting / stopping hot water filling to the bathtub 6, and a bathtub 6. A bath flow counter 31 that counts the amount of hot water filling and a check valve 32 that prevents the bath water from flowing back to the hot water supply pipe 27 are provided.

  Next, a plurality of hot water storage temperature sensors 33 are arranged in the vertical direction of the hot water storage tank 2, and in this embodiment, five hot water storage temperature sensors are arranged and are called 33a, 33b, 33c, 33d, 33e from the top. The amount of heat remaining in the hot water storage tank 2 is detected based on the temperature information detected by the temperature sensor 33, and the vertical temperature distribution in the hot water storage tank 2 is detected.

  The remote controller 5 is provided with a hot water supply temperature setting switch 34 for setting the hot water supply set temperature and a bath temperature setting switch 35 for setting the bath set temperature. An automatic bath switch 36 that fills the hot water by an amount of hot water set by a hot water filling amount setting switch (not shown) and keeps it warm for a predetermined time, and a reheating switch 37 that replenishes the bath water are provided.

  A hot water supply control unit 38 includes a microcomputer that receives the input of each sensor in the hot water storage tank unit 1 and controls driving of each actuator, and constitutes a control unit. The remote controller 5 is connected to the hot water supply control unit 38 by wireless or wired so that the user can set an arbitrary hot water set temperature and bath set temperature.

  Note that 39 is an overpressure relief valve for releasing the overpressure of the hot water storage tank 2, 40 is a pressure reducing valve for reducing the pressure of the water supply, 41 is a hot water supply flow rate counter for counting the amount of hot water to be supplied, and 42 is for detecting the temperature of the water supply. It is a feed water temperature sensor.

Next, the operation of the first embodiment will be described.
First, when the hot water storage temperature sensor 39 detects that the necessary amount of heat does not remain in the hot water storage tank 2 in the midnight power time zone, the hot water supply control unit 38 issues a boiling start command to the heat pump control unit 17. To emit. Upon receiving the command, the heat pump control unit 17 starts driving the heat pump after starting the compressor 11, and cools the low temperature water of about 5 to 20 ° C. taken out from the heat pump forward pipe 9 connected to the lower part of the hot water storage tank 2 as a refrigerant. -Heated to a high temperature of about 70 to 90 ° C by the water heat exchanger 12, returned to the hot water tank 2 from the heat pump return pipe 10 connected to the upper part of the hot water tank 2, and stacked in order from the upper part of the hot water tank 2 Store hot water. When the hot water storage temperature sensor 33 detects that the necessary amount of heat has been stored, the hot water supply control unit 38 issues a boiling stop command to the heat pump control unit 17, and the heat pump control unit 17 stops the compressor 11 and heat pump circulation. The pump 16 is also stopped to end the boiling operation.

  Next, the hot water supply operation will be described. When the hot water tap 4 is opened, the water supplied from the water supply pipe 8 flows into the hot water storage tank 2. Then, the hot water stored in the hot water storage tank 2 flows into the hot water supply mixing valve 25 through the hot water discharge pipe 7 and is mixed with the low temperature water from the hot water supply bypass pipe 26, and the hot water control section 38 sets the mixing ratio of the hot water supply mixing valve 28. The adjusted hot water at the hot water supply set temperature is supplied from the hot water tap 4. Then, the hot water supply is completed by closing the hot water tap 4.

  Next, the hot water filling operation to the bathtub 6 will be described. When the automatic bath switch 36 of the remote controller 5 is operated, the hot water supply control unit 38 opens the hot water filling valve 30. Then, the hot water adjusted to the set temperature by the hot water supply mixing valve 28 is poured from the hot water filling pipe 29 to the bathtub 6 through the hot water return pipe 21, and a bath flow rate counter 31 provided in the middle of the hot water filling pipe 29 is predetermined. When the amount of hot water filling is counted, the hot water supply control unit 38 closes the hot water filling valve 30 and ends the hot water filling operation.

  Next, the bath reheating operation will be described with reference to the flowchart shown in FIG. 2. When the reheating switch 37 of the remote controller 5 is turned on, the total hot water storage amount Q1 that can contribute to reheating by the hot water storage temperature sensors 33a to 33e. (Step 1, hereinafter abbreviated as S1). Since the bath water is heat-exchanged with the high-temperature water in the hot water storage tank 2 by the heat exchanger 18, the high-temperature water below the heat exchanger 18 can contribute to reheating. The stored hot water quantity Q1 that can contribute to reheating is a predetermined value assigned to each hot water storage temperature sensor 33a to 33e to a value obtained by subtracting the reheating target temperature or appropriate temperature from the temperature detected by each hot water storage temperature sensor 33a to 33e. It is calculated by adding the values multiplied by the capacity. If the temperature detected by each of the hot water storage temperature sensors 33a to 33e is lower than the reheating target temperature or an appropriate temperature (appropriate lower limit temperature that can be suitably used as a reheating heat source, for example, 50 ° C.), The negative amount of heat that does not contribute to the burning is not used in the calculation of the hot water storage amount Q1.

  Next, the hot water storage heat quantity Q2 near the heat exchanger 18 is calculated by the hot water storage temperature sensor 33b near the heat exchanger 18 (S2). Here, the heat set in advance is a value obtained by subtracting the target temperature for reheating from the temperature detected by the hot water storage temperature sensor 33b or an appropriate temperature (a suitable lower limit temperature that can be suitably used as a heat source for reheating, for example, 50 ° C.). This is calculated by multiplying a predetermined capacity near the exchanger 18.

  The total amount of stored hot water Q1 that can contribute to the reheating calculated in step S1 is equal to or greater than a predetermined predetermined heat amount Q3, and the amount of stored hot water Q2 near the heat exchanger 18 calculated in step S2 is determined in advance. It is determined whether the amount of heat is equal to or greater than a predetermined amount of heat Q4 (Q4 <Q3). If Q1> Q3 and Q2> Q4 (Yes in S3), the bath circulation pump 20 is started to start the bath reheating operation ( S4).

  When the temperature detected by the bath return temperature sensor 23 reaches the reheating target temperature (Yes in S5), the hot water supply control unit 38 stops driving the bath circulating pump 20 (S6) and ends the reheating operation (S6). S7).

  If it is determined in step S3 that Q1 ≦ Q3 or Q2 ≦ Q4 (No in S3), there is a possibility that the amount of heat may be insufficient during reheating, so the hot water supply control unit 38 is the same as the above-described boiling operation. In this manner, the heat pump control unit 17 is instructed to start the boiling operation, and the heat pump control unit 17 drives the heat pump circuit 15 and the heat pump circulation pump 16 to boil hot water in the hot water storage tank 2 (S8). . When the boiling increase operation is completed, the reheating operation is performed again from step S1.

  In this way, the start condition of the reheating operation was determined in consideration of both the total hot water storage amount Q1 that can contribute to the reheating in the hot water storage tank 2 and the hot water storage amount Q2 in the vicinity of the heat exchanger 18 in the hot water storage tank 2. As a result, it is possible to more accurately determine whether or not it is possible to drive the bath, and the convenience of the user can be greatly improved.

  Next, a second embodiment of the present invention will be described. The description of the same configuration as that of the first embodiment will be omitted, and the reheating operation will be described based on the flowchart shown in FIG.

  In the second embodiment, when the reheating switch 37 of the remote controller 5 is turned on, the total hot water storage amount Q1 that can contribute to reheating is calculated by the hot water storage temperature sensors 33a to 33e (S1).

  Next, the hot water storage temperature T in the vicinity of the heat exchanger 18 is detected by the hot water storage temperature sensor 33b (S9). Here, when heat exchange is performed between the hot water in the hot water storage tank 2 and the heat exchanger 18 provided in the hot water storage tank 2, the hot water below the upper end portion of the heat exchanger 18 contributes to the heat exchange. Moreover, since the city water is pushed up from below the hot water storage tank 2, the hot water storage temperature T in the vicinity of the heat exchanger 18 is substantially the same position as the height position where the heat exchanger 18 is provided, or a slightly lower position. It is desirable to detect with.

  The total hot water storage amount Q1 that can be contributed to the reheating calculated in the step S1 is not less than a predetermined predetermined heat amount Q3, and the hot water storage temperature T in the vicinity of the heat exchanger 18 detected in the step S9 is predetermined. It is determined whether the temperature is equal to or higher than a predetermined temperature T1 (appropriate lower limit temperature that can be suitably used as a heat source for reheating, for example, 50 ° C.). If Q1> Q3 and T> T1 (Yes in S10), the circulation is performed. The driving of the pump 20 is started and the refilling of the bath is started (S4).

  If it is determined in step S9 that Q1 ≦ Q3 or T ≦ T1 (No in S10), there is a possibility that the amount of heat may be insufficient during reheating, so the hot water supply control unit 38 performs the above-described boiling operation. Similarly, the heat pump control unit 17 is instructed to start the boiling operation, and the heat pump control unit 17 drives the heat pump circuit 15 and the heat pump circulation pump 16 to boil hot water in the hot water storage tank 2 (S8). ). When the boiling increase operation is completed, the reheating operation is performed again from step S1.

  In this way, the conditions for starting the reheating operation are determined in consideration of both the total hot water storage amount Q1 that can contribute to reheating in the hot water storage tank 2 and the hot water storage temperature T in the vicinity of the heat exchanger 18 in the hot water storage tank 2. As a result, it is possible to more accurately determine whether or not it is possible to drive the bath, and the convenience of the user can be greatly improved.

  In the first and second embodiments, the heat pump type is adopted as the means for heating the hot water, but the invention is not limited to this, and an electric heater may be disposed in the hot water tank 2.

The schematic block diagram of the hot water storage type hot-water supply apparatus of Examples 1-2 of this invention. FIG. 3 is a flowchart for explaining a chasing operation according to the first embodiment. FIG. 9 is a flowchart for explaining a chasing operation according to the second embodiment.

Explanation of symbols

2 Hot water storage tank 6 Bath 18 Heat exchanger 20 Bath circulation pump 22 Bath circulation circuit 33 Hot water storage temperature sensor

Claims (2)

  A hot water storage tank for storing hot water, a plurality of hot water temperature sensors for detecting the hot water storage temperature of the hot water storage tank, a bath circulation circuit having a bath circulation pump for circulating hot water in the bathtub, and the hot water storage tank in the middle of the bath circulation circuit And a heat exchanger that heats the bathtub water with hot water stored in the hot water storage tank, and drives the bath circulation pump to circulate the bathtub water to the heat exchanger for reheating operation. In the hot water storage type hot water supply apparatus, it is possible to calculate the hot water storage amount Q1 that can contribute to reheating by the plurality of hot water storage temperatures detected by the plurality of hot water storage temperature sensors and the hot water storage heat amount Q2 in the vicinity of the heat exchanger to contribute to reheating. The reheating operation can be started on the condition that the amount of stored hot water Q1 is not less than a predetermined amount of heat Q3 and the amount of stored hot water Q2 near the heat exchanger is not less than the predetermined amount of heat Q4. Hot-water storage type water heater that.   A hot water storage tank for storing hot water, a plurality of hot water temperature sensors for detecting the hot water storage temperature of the hot water storage tank, a bath circulation circuit having a bath circulation pump for circulating hot water in the bathtub, and the hot water storage tank in the middle of the bath circulation circuit And a heat exchanger that heats the bathtub water with hot water stored in the hot water storage tank, and drives the bath circulation pump to circulate the bathtub water to the heat exchanger for reheating operation. In the hot water storage type hot water supply apparatus, the hot water storage heat amount Q1 that can contribute to reheating is calculated by the plurality of hot water storage temperatures detected by the plurality of hot water storage temperature sensors, and the hot water storage heat amount Q1 that can contribute to reheating is greater than or equal to a predetermined heat amount Q3. And the hot water storage type hot water supply machine which enabled the reheating operation to be started on condition that the hot water storage temperature in the vicinity of the heat exchanger is equal to or higher than T1.

Images