JP2001280695A - Heat pump water-heater - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a heat pump water-heater for making hot water in a hot-water storage tank by a heat-pump type heater. SOLUTION: A first motorized selector valve 13 is provided between the center of a hot-water storage tank 1 and a condenser 6 through a pipe. A second motorized selector valve 14 is provided between an outlet of the tank 1 and high temperature water of a mixing valve 11 through a pipe. Further a third motorized selector valve 15 is provided between a water source and low temperature water of the mixing valve 11 through a pipe.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat pump water heater for boiling water in a hot water storage tank.

[0002]

2. Description of the Related Art FIG. 5 is a system configuration diagram showing a conventional heat pump water heater. In FIG. 5, 1 is a hot water storage tank, 2 is a heating element provided in the hot water storage tank 1 for heating water, and 3 is attached to an outer wall portion below the hot water storage tank 1 to control the temperature of the water in the tank 1. It is a temperature detector to detect. Reference numeral 4 denotes a heat pump type heating device for heating water in the hot water storage tank 1, and includes a compressor 5, a condenser 6, a decompression device 7,
The evaporator 8 is constituted by a refrigerant circuit connected in order.

Further, a circulation pump 9 for circulating water through a pipe connected to a condenser 6 constituting the heat pump type heating device 4 and a flow rate regulating valve 10 for regulating a circulation flow rate of water are provided. Further, a mixing valve 11 is provided via a pipe connected to an outlet located above the hot water storage tank 1. Reference numeral 12 denotes a control unit for intermittently performing operations of the heating element 2, the heat pump heating device 4, and the circulation pump 9 based on the output from the temperature detector 3.

[0004] Next, the boiling operation of the heat pump water heater having such a configuration will be described with reference to a system configuration diagram shown in FIG. After the water is supplied into the hot water storage tank 1 from its lower part and the tank is full, the boiling operation is started. As a result, the compressor 5 starts operating, and the compressed primary refrigerant gas flows toward the condenser 6 through the pipe. Then, the pressure of the primary refrigerant gas flowing out of the condenser 6 is reduced by the pressure reducing device 7, and the secondary refrigerant gas maintained at the low pressure level flows toward the evaporator 8. Due to such a flow of the refrigerant, the condenser 6 side becomes a high temperature state and the evaporator 8 side becomes a low temperature state. Next, the water in the hot water storage tank 1 escapes from the lower part thereof,
0, and enters from the central part of the hot water storage tank 1 via the condenser 6 maintained at a high temperature.

Then, the water in the hot water storage tank 1 escapes from the lower part again, passes through the condenser 6 from the circulation pump 9 and enters from the central part of the hot water storage tank 1. By such a water circulation operation, the water in the hot water storage tank 1 is heated to a predetermined temperature through the condenser 6, and is stacked from above in the hot water storage tank 1 due to a temperature difference from the water. Note that the heating element 2 is provided to prevent the condenser 6 from being heated due to a failure of the compressor 5 or the like or from being unable to supply predetermined high-temperature water due to the outside air temperature. Next, high-temperature water is produced in the hot-water storage tank 1, and the high-temperature water is supplied to the high-temperature water side (portion A in FIG. 5) of the mixing valve 11, and water from the water source is supplied to the low-temperature water side of the mixing valve 11. (Part B in FIG. 5). Then, hot water in an appropriate temperature state is produced by the mixing valve 11 and supplied to, for example, a bathtub side or a faucet side.

[0006]

A conventional heat pump water heater stores a high-temperature water in a hot water storage tank as described above, and supplies hot water discharged from a mixing valve to a bathtub side and a faucet side as necessary. It has become. However, when a large amount of high-temperature water in the hot water storage tank is used, for example, on the bathtub side or the faucet side, water corresponding to the usage amount is supplied into the hot water storage tank. As a result, the temperature of the high-temperature water in the hot water storage tank decreases, and a problem occurs in which hot water lower than the set temperature flows out of the mixing valve, that is, "out of hot water".

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems. Even when a large amount of high-temperature water in a hot water storage tank is used on a bathtub side and a faucet side, the set temperature is always set from a mixing valve. It is intended to prevent hot water from flowing out of the hot water kept in the bath.

[0008]

A heat pump water heater according to the present invention includes a hot water storage tank, a circulation pump for circulating water in the hot water storage tank through a first flow path, and a circulation pump in the middle of the first flow path. In a heat pump water heater including a heat pump heating device that heats water and a second flow path that supplies high-temperature water stored in a hot water storage tank to a hot water mixing valve,
A flow path control unit is provided for flowing high-temperature water heated by a heat pump type heating device directly to a hot water mixing valve without being circulated to a hot water storage tank.

Further, a temperature detector for detecting the temperature of the high-temperature water in the hot water storage tank is provided, and when the output from the temperature detector becomes equal to or less than a predetermined value, the flow path controller is heated by a heat pump type heating device. Without circulating the hot water to the hot water storage tank,
It flows directly to the hot water mixing valve.

[0010] Further, the flow path control section circulates the high-temperature water heated by the heat pump type heating device to the hot water storage tank only at midnight.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 1 and 2 are system configuration diagrams showing a first embodiment of a heat pump water heater according to the present invention, and FIG. 3 is a flowchart showing an operation flow of the system configuration. 1 and 2,
The same reference numerals as those in the conventional example indicate the same or corresponding parts. 13
Is a first motor-operated switching valve connected via a pipe between the center of the hot water storage tank 1 and the condenser 6, and 14 is an outlet of the hot water storage tank 1 and the high temperature water side of the mixing valve 11 (FIGS. 1 and 2). A second motor-operated directional control valve connected to the water source side and the low-temperature water side of the mixing valve 11 (part D in FIGS. 1 and 2).
And a third motor-operated directional control valve connected via a pipe.

Next, the boiling operation of the heat pump water heater will be described with reference to the system configuration diagram shown in FIGS. 1 and 2 and the flowchart shown in FIG. In FIG. 1, when the boiling operation is started after water is supplied from the lower part in the hot water storage tank 1 to reach a full state (step S10).
0), the condenser 6 enters a heating state, and the circulation pump 9 performs a series of operations for circulating the water in the hot water storage tank 1, that is, a boiling operation (step S101). Thereby, the water in the hot water storage tank 1 escapes from the lower part and flows from the circulation pump 9 to the flow control valve 10. Then, the water passes through the condenser 6 in a high-temperature state and passes through the first electric switching valve 13 from the IN side to the OUT side of the hot water storage tank 1.
Enter from the center of. Thereafter, the above-described operation content is repeated.

Next, during the process of circulating and heating the water in the hot water storage tank 1, the boiling temperature Ts is detected (step S102), and the control unit 12 sets the boiling temperature Ts to a predetermined temperature T1, for example, 90 ° C. It is determined whether or not it has been performed (step S103). Here, if NO, that is, the boiling temperature Ts does not reach the predetermined temperature T1, the above-described operation is repeated. If YES, the boiling temperature Ts has reached the predetermined temperature T1, so that the condenser 6 and the like are controlled so as to be maintained at the temperature T1, and an operation for preventing "running out of hot water" is started (step S1). S104). In this process, the high-temperature water equivalent to 90 ° C. in the hot-water storage tank 1 escapes from the outlet thereof, and flows from the IN side to the OUT side of the second electric switching valve 14 to the high-temperature water side of the mixing valve 11 (C in FIG. 1). The water from the water source flows from the IN side to the OUT side of the third electric switching valve 15 to the low temperature water side (D part in FIG. 1) of the mixing valve 11, respectively.

Next, the controller 12 determines whether the boiling temperature Ts is equal to or lower than a predetermined temperature T2, for example, 80 ° C. (step S105). The predetermined temperature T2 is a temperature threshold value assuming that the remaining hot water in the hot water storage tank 1 flows to the mixing valve 11 and that the hot water flowing out of the mixing valve 11 is about to run out of hot water. Here, suppose that NO, that is, the boiling temperature Ts is 80 ° C.
If it is determined that it is not less than the above, the boosting operation by the condenser 6 is not started. If YES, that is, if it is determined that the boiling temperature Ts is equal to or lower than 80 ° C., the user may use the hot water in the hot water storage tank 1 in a large amount on the bathtub side or the faucet side, thereby causing the “out of hot water”. It is determined that there is a high possibility of occurrence, and a boosting operation by the condenser 6 is executed (step S106). It is impossible to maintain the temperature of the high-temperature water at 90 ° C. in this additional boiling operation, and it is premised that the temperature is kept at a temperature lower than 90 ° C.

Next, as shown in FIG. 2, the first electric switching valve 13 and the second electric switching valve 14 are switched (step S107). It flows toward the condenser 6 maintained in the state. The high-temperature water heated by the condenser 6 passes from the IN side to the OUT side of the first electric switching valve 13, and further passes from the IN side to the OUT side of the second electric switching valve 14, and the high-temperature water side of the mixing valve 11 ( (C in FIG. 2). At this time, the water from the water source flows from the IN side to the OUT side of the third electric switching valve 15 and the low temperature water side of the mixing valve 11 (D in FIG. 2).
Section), hot water is discharged from the mixing valve 11 at the set temperature.

Next, the control unit 12 allows the user to
It is determined whether or not a time zone in which the high-temperature water is hardly used, that is, a midnight time zone has been entered (step S108). Here, if NO, that is, if the time is outside the midnight time zone, the boiling temperature T
It is determined whether s is equal to or lower than a predetermined temperature T2 (step S105). Subsequent steps are the same as described above. If the answer is YES, that is, if the time is midnight, the first electric switching valve 13 and the second electric switching valve 14 are switched to the state shown in FIG. 1 (step S109). Then, a boiling operation of returning hot water in the hot water storage tank 1 in the hot water storage tank 1 to the hot water storage tank 1 through a predetermined flow path through the condenser 6 which maintains a high temperature state at midnight is executed. (Step S101). Thereby, the hot water storage tank 1
High temperature water can be stored again inside.

The heat pump water heater having such a configuration passes through the condenser 6 when it is judged that the user is likely to use a large amount of high-temperature water in the hot-water storage tank 1 to cause "out of hot water". Since the high-temperature water is not returned into the hot-water storage tank 1 but flows directly to the high-temperature water side of the mixing valve 11, it is possible to prevent a "water shortage" situation.

In the process of determining whether or not the boiling temperature Ts is equal to or lower than the predetermined temperature T2 (step S2).
105) If YES, that is, if there is a high possibility of causing “running out of hot water”, as shown in FIG.
And the third electric switching valve 15 is switched. Then, the high-temperature water that has passed through the condenser 6 is passed from the IN side of the first electric switching valve 13 to the OUT side, and further from the IN side of the third electric switching valve 4 to the OUT side. Next, the high-temperature water is mixed with mixing valve 1
1. The hot water in the hot water storage tank 1 flows from the IN side of the second electric switching valve 14 to the low temperature water side (D part in FIG.
Pass through the T side and pass the high temperature water side of the mixing valve 11 (C in FIG. 4).
Section).

[0019]

Since the present invention is configured as described above, it has the following effects.

The heat pump water heater according to the present invention comprises:
A hot water storage tank, a circulating pump for circulating water in the hot water storage tank through the first flow path, a heat pump heating device for heating the circulating water in the middle of the first flow path, and high-temperature water stored in the hot water storage tank Control in a heat pump water heater provided with a second flow path for supplying water to a hot water mixing valve, wherein high temperature water heated by the heat pump heating device is directly circulated to the hot water mixing valve without being circulated to the hot water storage tank. Since the section is provided, when the user uses a large amount of high-temperature water in the hot-water storage tank, the control section can immediately predict a "water-out" situation and switch the flow path of the high-temperature water.

Further, a temperature detector for detecting the temperature of the high-temperature water in the hot water storage tank is provided, and when the output from the temperature detector falls below a predetermined value, the flow path is heated by a heat pump type heating device. Without circulating the hot water to the hot water storage tank,
Since the hot water is directly supplied to the hot water mixing valve, the hot water in the “hot water out” state in the hot water storage tank can be boiled again to produce high-temperature water. Therefore, even if the user uses a large amount of hot water produced by the mixing valve in the bathtub or faucet,
It is possible to prevent low-temperature water peculiar to "water drainage" from being discharged.

Further, the flow path control section circulates the high-temperature water heated by the heat pump type heating device to the hot water storage tank only during the late night hours, so that the hot water in the hot water storage tank reaches a "hot drain" state. Even in this case, when using the hot water the next day, hot water maintained at a predetermined temperature can be supplied.

[Brief description of the drawings]

FIG. 1 is a system configuration diagram showing Embodiment 1 of a heat pump water heater according to the present invention.

FIG. 2 is another system configuration diagram showing the first embodiment.

FIG. 3 is a flowchart showing an operation flow of a system configuration according to the first embodiment;

FIG. 4 is still another system configuration diagram showing the first embodiment.

FIG. 5 is a system configuration diagram of a conventional heat pump water heater.

[Explanation of symbols]

1 hot water storage tank, 2 heating element, 3 temperature detector, 4 heat pump heating device, 5 compressor, 6 condenser, 7
Decompression device, 8 evaporator, 9 circulation pump, 10 flow control valve, 11 mixing valve, 12 control unit, 13 first electric switching valve, 14 second electric switching valve, 15 third electric switching valve.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Tetsuji Shichido 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Mitsui Electric Co., Ltd. (72) Inventor Masaki Toshima 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Mitsubishi Electric Corporation

Claims (3)

[Claims] 1. A hot water storage tank, a circulation pump for circulating water in the hot water storage tank through a first flow path,
A heat pump type heating device for heating the circulating water in the middle of the flow path, and a second flow path for supplying high-temperature water stored in the hot water storage tank to the hot water mixing valve. A heat pump water heater comprising: a flow path control unit that directly flows high-temperature water heated by a heating device to the hot water mixing valve without circulating the high-temperature water to a hot water storage tank. 2. A temperature detector for detecting a temperature of high-temperature water in the hot water storage tank, wherein the flow path control unit performs the heat pump heating when an output from the temperature detector becomes a predetermined value or less. The heat pump water heater according to claim 1, wherein the high-temperature water heated by the device is directly circulated to the hot water mixing valve without being circulated to the hot water storage tank. 3. The heat pump water heater according to claim 1, wherein the flow path control section circulates the high-temperature water heated by the heat pump heating device to the hot water storage tank only during late night hours.