WO2014133054A1

WO2014133054A1 - Hot-water supply device

Info

Publication number: WO2014133054A1
Application number: PCT/JP2014/054795
Authority: WO
Inventors: 稔久田子; 速彦高城; 智志井田; 晴之布下; コーリー・ジヨージ・エル; オーソー・ジルダ
Original assignee: サンデン株式会社
Priority date: 2013-03-01
Filing date: 2014-02-27
Publication date: 2014-09-04
Also published as: JP2014169807A

Abstract

[Problem] To provide a low-cost, space-saving hot-water supply device with which the size of the hot-water storage tank can be reduced, and with which the risk of running out of hot water can be avoided when the size of the hot-water storage tank is reduced. [Solution] The present invention is configured so as to be equipped with a hot-water storage tank (1) that stores high-temperature water to be supplied to the outside, thermostats (3, 4) for detecting the water temperature inside the hot-water storage tank (1), a heat pump unit (2) that operates on the basis of the water temperature detected by the thermostat (3), heating low-temperature water entering from the lower part of the hot-water storage tank (1) and returning this water to the upper part of the hot-water storage tank (1), and an electric heater (5) that operates on the basis of the water temperature detected by the thermostat (4), heating the water inside the hot-water storage tank (1), with the thermostat (4), the thermostat (3), and the electric heater (5) being arranged in that order from the upper part to the lower part of the hot-water storage tank (1).

Description

Water heater

The present invention relates to a hot water supply apparatus using a heat pump, and more particularly to a hot water supply apparatus that can reduce the risk of running out of hot water when a hot water storage tank is downsized.

Recently, the use of water heaters using heat pumps is expanding from the viewpoint of energy saving. This type of hot water supply device is a hot water storage tank, a water supply pipe that supplies low temperature water to the lower part of the hot water storage tank, connected to the hot water storage tank by piping, and heats the water from the lower part of the tank to form hot water (hot water). A heat pump unit that returns to the top, a hot water supply pipe that supplies the hot water stored in the hot water storage tank to the outside, and the like (see, for example, Patent Document 1). In this hot water supply device, when hot water in the hot water storage tank is used, low temperature water is supplied to the lower part of the tank according to the amount used, and the hot water storage tank has a high temperature water layer (hot water layer) and a low temperature water layer (water). Layer) and a mixed layer at the boundary between the two layers (a layer of lukewarm water in which hot water and water are mixed), the amount of low-temperature water increases as hot water is used, and the mixed layer moves to the top of the tank. Therefore, a temperature detector that also functions as a residual hot water detector is placed at the appropriate location in the hot water storage tank, and when the temperature detector detects a temperature lower than the predetermined hot water temperature, it is determined that the remaining amount of hot water is low, and the heat pump unit is installed. It operates to heat the water in the lower part of the hot water tank and return it to the upper part of the hot water tank to prevent the hot water from running out (hot water running out).

JP 2008-116131 A

By the way, when such a hot water supply device is installed, for example, in a detached house or an apartment house, downsizing of the hot water storage tank is desired in order to reduce the installation space of the hot water supply device. However, if the hot water storage tank is downsized, the amount of hot water that can be stored decreases, and therefore, when the amount of hot water used is larger than usual, there is a problem that the hot water tends to run out.

The present invention has been made paying attention to the above problems, and an object of the present invention is to provide a hot water supply apparatus that can avoid the risk of running out of hot water when the hot water storage tank is downsized, and that can reduce the size of the hot water storage tank.

For this reason, the first aspect of the hot water supply apparatus of the present invention includes a hot water storage tank for storing high-temperature water supplied to the outside, first and second temperature detection means for detecting the water temperature in the hot water storage tank, and the first A heat pump unit that operates based on the detected water temperature of the temperature detecting means and heats the low-temperature water entering from the lower part of the hot water tank and returns it to the upper part of the hot water tank, and based on the detected water temperature of the second temperature detecting means Auxiliary heating means that operates to heat the water in the hot water storage tank, and from the upper part to the lower part of the hot water storage tank in the order of the second temperature detection means, the first temperature detection means, and the auxiliary heating means. It is characterized by arranging.

Moreover, the 2nd aspect of the hot water supply apparatus of this invention is the hot water storage tank which stores the high temperature water supplied outside, the 1st temperature detection means which detects the water temperature in this hot water storage tank, and the said 1st temperature detection means. A heat pump unit that operates based on the detected water temperature to heat low-temperature water entering from the lower part of the hot water storage tank and return it to the upper part of the hot water storage tank, and detects the incoming water temperature that enters the heat pump unit from the lower part of the hot water storage tank And a supplementary heating means that operates based on the detected water temperature of the fourth temperature detection means and heats the water in the hot water storage tank, and has a temperature detected by the first temperature detection means. On the basis of the water temperature detected by the fourth temperature detecting means before the elapse of a predetermined time from the start of the heating operation by the heat pump unit. Characterized by being configured to start the heating operation of the unit.

According to the hot water supply apparatus of the present invention, the auxiliary heating means is activated when the amount of hot water (hot water) stored in the hot water storage tank is large and the production of hot water (hot water) by the heat pump unit is not in time. Since the water in the hot water storage tank is heated, the risk of running out of hot water when the hot water storage tank is downsized can be avoided. Therefore, the hot water storage tank can be downsized, and a low-cost and space-saving hot water supply device can be provided.

It is a schematic block diagram of 1st Embodiment of the hot water supply apparatus which concerns on this invention. It is a block diagram of the control part of 1st Embodiment same as the above. It is a schematic block diagram of 2nd Embodiment of the hot water supply apparatus which concerns on this invention. It is a block diagram of the control part of 2nd Embodiment same as the above. It is a schematic block diagram of 3rd Embodiment of the hot water supply apparatus which concerns on this invention. It is a block diagram of the control part of 3rd Embodiment same as the above.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic configuration diagram of a first embodiment of a hot water supply apparatus of the present invention.
In FIG. 1, a hot water supply apparatus of this embodiment includes a hot water storage tank 1, a heat pump unit 2,

thermostats

3 and 4 as first and second temperature detection means, an electric heater 5 as auxiliary heating means, and heater control. Part 6.

The hot water storage tank 1 stores high-temperature water (for example, 65 ° C. hot water) heated by the heat pump unit 2, a water supply pipe 7 for supplying low-temperature water (city water, etc.) to the lower part of the hot water storage tank 1, and hot water storage A connecting pipe 8 for introducing low-temperature water at the bottom of the tank 1 into the water inlet of the heat pump unit 2 is connected to substantially the same height position near the bottom of the hot water storage tank 1. Further, the hot water storage tank 1 supplies the hot water (hot water) heated from the water discharge part of the heat pump unit 2 to the upper part of the hot water storage tank 1, and supplies the hot water in the hot water storage tank 1 to an external bathtub or kitchen. The hot water supply pipe 10 is connected to substantially the same height near the top of the hot water storage tank 1.

As shown in FIG. 2, the heat pump unit 2 includes a heat pump 2A that heats low-temperature water that enters from the hot water storage tank 1 through the connection pipe 8, and a pump control unit 2B that controls the driving of the heat pump 2A. The heat pump 2A includes a compressor, a condenser (heat exchanger), an expansion valve, and an evaporator (heat exchanger) in the circulation path of a refrigerant (for example, CO ₂ ), and takes in the heat of air by the evaporator. The low temperature water that has entered the hot water storage tank 1 through the connection pipe 8 is heated by the condenser, and the hot water is returned to the hot water storage tank 1 through the connection pipe 9. The pump control unit 2B operates the heat pump 2A based on the detected water temperature in the hot water storage tank 1 detected by the thermostat 3 serving as the first temperature detection means, and enters the heat pump unit 2 from the hot water storage tank 1 through the connection pipe 8. The heating operation of the heat pump 2A is stopped and controlled based on the detected water temperature of the thermostat 11 that detects the temperature of the low-temperature water based on, for example, the water temperature of the connection pipe 8. In this embodiment, the thermostat 11 is disposed outside the heat pump unit 2, but is incorporated into the heat pump unit 2 as a part of the heat pump unit 2, and the incoming water temperature is set at the connection pipe 8 in the heat pump unit 2. It may be detected.

The

thermostats

3 and 4 detect the water temperature in the hot water storage tank 1. The thermostat 3 detects a predetermined water temperature t1 (a temperature lower than the water temperature supplied from the connection pipe 9 to the upper portion of the hot water tank 1). For example, the thermostat 3 is turned on when it is detected that the water temperature is equal to or lower than t1. . The thermostat 4 detects a predetermined water temperature t2 (a temperature lower than the water temperature supplied from the connection pipe 9 to the upper portion of the hot water tank 1). For example, the thermostat 4 is turned on when it is detected that the water temperature is equal to or lower than t2. . And when

thermostats

3 and 4 detect water temperature t1 and t2 lower than the temperature of high temperature water (for example, 65 degreeC), it can be judged that the quantity of high temperature water has decreased to each attachment position of

thermostats

3 and 4. The

thermostats

3 and 4 also have a role of a remaining hot water detection sensor. The thermostat 11 that detects the water temperature of the connecting pipe 8 is turned from on to off when detecting that the detected water temperature is equal to or higher than a predetermined water temperature t3 set in advance, for example.

The electric heater 5 is auxiliary heating means when the heating capacity of the heat pump unit 2 is insufficient, and operates based on the detected water temperature of the thermostat 4 to heat the water in the hot water storage tank 1.

The

thermostats

3 and 4 and the electric heater 5 are attached to the hot water storage tank 1, and are arranged in the order of the thermostat 4, the thermostat 3 and the electric heater 5 from the upper part to the lower part of the hot water storage tank 1 as shown in FIG. ing. Specifically, the thermostat 4 is disposed below the tank opening at the tip of the hot water supply pipe 10 bent upward in the hot water storage tank 1 in the upper part of the hot water storage tank 1. The thermostat 3 is disposed in a substantially central region of the hot water storage tank 1. The electric heater 5 is below the hot water storage tank 1 and above the tank opening at the tip of the water supply pipe 7 connected to the lower part of the hot water storage tank 1 at substantially the same height as the connection pipe 8 and bent downward in the hot water storage tank 1. Is arranged.

The heater control unit 6 drives and controls the electric heater 5 based on the detected water temperature in the hot water storage tank 1 detected by the thermostat 4 as the second temperature detecting means, and based on the water temperature of the connection pipe 8 detected by the thermostat 11. The heating operation of the electric heater 5 is stopped and controlled by a stop command signal transmitted from the pump control unit 2B.

In FIG. 1, reference numeral 12 denotes a power supply line that supplies drive power to the heat pump unit 2 and the heater control unit 6.

Next, the operation of this hot water supply apparatus will be described.
When the hot water storage tank 1 is filled with high-temperature water, the heat pump unit 2 is in a stopped state, and the

thermostats

3 and 4 are off. In this state, when the high temperature water in the upper part of the hot water storage tank 1 is supplied to the outside through the hot water supply pipe 10 and the amount of the high temperature water in the hot water storage tank 1 is reduced, the low temperature water is supplied from the water supply pipe 7 according to the decrease amount. It is supplied to the lower part of the hot water storage tank 1. Thereby, in the hot water storage tank 1, a high temperature water layer is formed on the upper side, a low temperature water layer is formed on the lower side, and a mixed layer in a warm water state in which high temperature water and low temperature water are mixed is formed in the boundary region. And the position of the mixed layer of the boundary area | region of a high temperature water layer and a low temperature water layer rises as the amount of hot water of the upper part of the hot water storage tank 1 is used and it reduces. When the thermostat 3 detects and turns on the predetermined water temperature t1 lower than the high temperature water, the pump controller 2B determines that the remaining hot water amount has been reduced by the input of the ON signal, and drives and controls the compressor of the heat pump 2A. The heat pump 2A is activated. Thereby, high temperature water is supplied to the upper part of the hot water storage tank 1 from the connection pipe 9.

When the amount of hot water supply is larger than the supply of high-temperature water from the heat pump unit 2 and the amount of high-temperature water further decreases and the thermostat 4 detects a predetermined water temperature t2 lower than the high-temperature water and turns on, the heater control unit is activated by the input of the ON signal. 6 actuates the electric heater 5. Thereby, in addition to the supply of high temperature water from the heat pump unit 2, the water in the hot water storage tank 1 is heated by the electric heater 5, and by using the heat pump 2 A and the electric heater 5 in combination, the high temperature water is discharged from the unit 2 hot water storage tank 1. Avoid the risk of running out of hot water.

Thereafter, by the heating operation of the heat pump unit 2 and the electric heater 5, the amount of high-temperature water in the hot water storage tank 1 increases and the water temperature in the connection pipe 8 rises, and the hot water tank 1 passes through the connection pipe 8 to the heat pump unit 2. When the water temperature of the incoming (low temperature) water becomes equal to or higher than the predetermined water temperature t3, the thermostat 11 is turned off. The pump control unit 2B stops the heating operation of the heat pump unit 2 by stopping the compressor of the heat pump 2A by inputting the off signal, and transmits a stop command signal for the electric heater 5 to the heater control unit 6. The heater control unit 6 stops the operation of the electric heater 5 in response to the input of the stop command signal.

According to such a hot water supply device, when the amount of hot water in the hot water storage tank 1 increases and the generation of hot water by the heat pump unit 2 is not in time, the electric heater 5 is driven to use the heat pump unit 2 and the electric heater 5 together. Since the water in the hot water storage tank 1 is heated, the risk of running out of hot water can be avoided even when the hot water storage tank 1 has a small volume and a small amount of hot water stored. Therefore, the hot water storage tank can be downsized, and a low-cost and space-saving hot water supply device can be provided.
Moreover, since the heat pump 2A and the electric heater 5 are independently driven by the pump control unit 2B and the heater control unit 6, even if the heat pump 2A side fails, the electric heater 5 heats the water in the hot water storage tank 1 The hot water storage tank 1 can store hot water. In addition, since the electric heater 5 is attached in the vicinity of the bottom of the hot water storage tank 1, a large amount of high-temperature water can be stored in the hot water storage tank 1 with only the electric heater 5.

3 and 4 show a second embodiment of the hot water supply apparatus of the present invention, FIG. 3 is a schematic configuration diagram, and FIG. 4 is a configuration diagram of a control unit. In addition, the same code | symbol is attached | subjected to the same element as 1st Embodiment, and description is abbreviate | omitted.
In FIG. 3, this hot water supply apparatus has a thermostat 20 disposed as a third temperature detecting means in the vicinity of the electric heater 5 below the hot water tank 1, for example, below the electric heater 5, as shown in FIG. The difference from the first embodiment is that the heating operation of the electric heater 5 is controlled to stop based on the water temperature. Other configurations are the same as those of the first embodiment. Note that the position of the thermostat 20 as the third temperature detection means may be in the vicinity of the electric heater 5, and may be the same height or above.

The thermostat 20 turns from on to off when it is detected that the detected water temperature at or near the same height as the electric heater 5 is equal to or higher than a predetermined water temperature t4 set in advance, for example. The water temperature t4 may be the same as or different from the detected water temperature t3 of the thermostat 11 of the first embodiment.

This water heater differs from the first embodiment in the heating stop control of the electric heater 5. That is, when the amount of hot water in the hot water storage tank 1 is increased by the heating operation of the heat pump unit 2 and the electric heater 5 and the water temperature in the lower part of the hot water storage tank 1 is increased to the water temperature t4 or more, the thermostat 20 is turned off. The heater control unit 6 controls to open the energization circuit of the electric heater 5 and stops the operation of the electric heater 5 by inputting the off signal of the thermostat 20. Since the operations other than the above-described heating stop control of the electric heater 5 are the same as those in the first embodiment, description thereof is omitted here.

According to such a hot water supply device, the water temperature detection information of the thermostat 11 is not required in the drive control of the electric heater 5, and the stop command signal of the electric heater 5 from the pump control unit 2B to the heater control unit 6 as shown in FIG. The transmission path can be eliminated, and the control of the heat pump unit 2 side and the electric heater 5 side can be completely separated. Therefore, even when a failure related to the thermostat 11 occurs on the heat pump unit 2 side and the heat pump unit 2 cannot be driven, high-temperature water can be stored in the hot water storage tank 1 using only the electric heater 5.

5 and 6 show a third embodiment of the hot water supply apparatus of the present invention, FIG. 5 is a schematic configuration diagram, and FIG. 6 is a configuration diagram of a control unit. In addition, the same code | symbol is attached | subjected to the same element as 1st Embodiment, and description is abbreviate | omitted.
This hot water supply apparatus is configured to control the operation of the electric heater 5 based on the detected water temperature of the thermostat 11 that detects the temperature of water entering the heat pump unit 2 via the connection pipe 8 without attaching the thermostat 4. Specifically, the heating operation of the electric heater 5 is started when the detected water temperature of the thermostat 11 does not exceed a predetermined water temperature before the predetermined time elapses after the heat pump unit 2 starts the heating operation. . Therefore, in this embodiment, the thermostat 11 has a role of a 4th temperature detection means. In addition, since it is the same as that of 1st Embodiment except the operation control form of the electric heater 5, operation control of the electric heater 5 is demonstrated here and description is abbreviate | omitted about another operation | movement.

The operation control of the electric heater by this hot water supply device will be described.
When the hot water stored in the hot water storage tank 1 is reduced and the thermostat 3 detects a predetermined water temperature t1 lower than the high temperature water and is turned on while being filled with the high temperature water in the hot water storage tank 1, the ON signal is input. The pump control unit 2 </ b> B controls the operation of the heat pump 2 </ b> A and supplies hot water to the hot water storage tank 1. At the same time, the pump control unit 2B starts measuring the elapsed time after the thermostat 3 is turned on. Then, when the elapsed time after the thermostat 3 is turned on reaches a predetermined time set in advance, it is determined whether or not the thermostat 11 is in an off state. The predetermined time is set in advance based on, for example, the capacity of the heat pump unit 2 or the volume of the tank on the lower side from the mounting position of the thermostat 3 of the hot water storage tank 1. Specifically, for example, the heat pump unit 2 performs a heating operation. The time from the start until the detected water temperature of the thermostat 11 becomes equal to or higher than a predetermined water temperature is calculated, and this calculated value is set as the predetermined time. When the elapsed time after the thermostat 3 is turned on reaches a predetermined time, when the thermostat 11 is in an off state, that is, water that enters the heat pump unit 2 from the hot water storage tank 1 via the connection pipe 8 (low temperature). When the water temperature is still lower than the predetermined water temperature t3, the pump control unit 2B determines that the supply of high-temperature water to the hot water storage tank 1 is insufficient and transmits an operation command signal for the electric heater 5 to the heater control unit 6. The heater control unit 6 operates the electric heater 5.

Thereafter, when the temperature of the water entering the heat pump unit 2 from the hot water storage tank 1 via the connection pipe 8 exceeds the predetermined water temperature and the thermostat 11 is turned on by the heating operation of the heat pump unit 2 and the electric heater 5. The pump control unit 2B stops the heating operation of the heat pump unit 2 and transmits a stop command signal for the electric motor 5 to the heater control unit 6, and the heater control unit 6 inputs the stop command signal to Stop operation.

Such a hot water supply apparatus has the advantage that the number of thermostats can be reduced and the number of parts can be reduced, in addition to the same effects as the first embodiment.

In addition, although the attachment position of the electric heater 5 may be substantially the same height as the thermostat 3, it is desirable to attach to the lower part of the hot water storage tank 1 below the thermostat 3 as in the above embodiments. By so doing, more hot water can be generated by the electric heater 5.

Further, the detected water temperatures t1 and t2 of the

thermostats

3 and 4 may be the same or different.

Further, the mounting position of the

thermostats

3 and 4 is not limited to the above-described embodiment, and an appropriate position may be selected according to, for example, the capacity of the hot water storage tank 1 or the capacity of the heat pump unit 2.

In each embodiment, a thermostat is used as the temperature detection means, but other temperature sensitive elements such as a thermistor may be used as the temperature detection means.

DESCRIPTION OF SYMBOLS 1 Hot water storage tank 2 Heat pump unit 2A Heat pump 2B

Pump control part

3, 4, 11, 20 Thermostat 5 Electric heater 6 Heater control part

Claims

A hot water storage tank for storing hot water to be supplied to the outside,
First and second temperature detecting means for detecting the water temperature in the hot water storage tank;
A heat pump unit that operates based on the detected water temperature of the first temperature detecting means and heats low-temperature water entering from the lower part of the hot water storage tank and returns it to the upper part of the hot water storage tank;
Auxiliary heating means that operates based on the detected water temperature of the second temperature detection means to heat the water in the hot water storage tank;
With
A hot water supply apparatus, wherein the hot water storage tank is disposed in order of the second temperature detection means, the first temperature detection means, and the auxiliary heating means from the upper part to the lower part of the hot water storage tank.
The hot water supply apparatus according to claim 1, wherein the second temperature detecting means is disposed in the vicinity of a tank opening of a hot water supply pipe for supplying high temperature water to the outside from an upper part of the hot water storage tank.
The auxiliary heating means is a lower part of the hot water storage tank, and a tank opening part of a water supply pipe for supplying low-temperature water to the lower part of the hot water storage tank and a tank opening part of a connecting pipe for introducing the water in the lower part of the hot water storage tank into the heat pump unit The hot-water supply apparatus of Claim 1 or 2 arrange | positioned more upwards.
The hot water supply apparatus according to any one of claims 1 to 3, wherein the heating operation of the auxiliary heating means is controlled to stop based on a water temperature that enters the heat pump unit from a lower part of the hot water storage tank.
A third temperature detecting means is disposed in the vicinity of the auxiliary heating means below the hot water storage tank, and the heating operation of the auxiliary heating means is controlled to stop based on the detected water temperature of the third temperature detecting means. The hot water supply apparatus as described in any one of these.
The hot water supply apparatus according to claim 5, wherein the third temperature detecting means is disposed at the same height as the auxiliary heating means or below the auxiliary heating means.
The hot water supply device according to claim 5 or 6, wherein the heat pump unit and the auxiliary heating means can be driven independently of each other.
A hot water storage tank for storing hot water to be supplied to the outside,
First temperature detecting means for detecting the water temperature in the hot water storage tank;
A heat pump unit that operates based on the detected water temperature of the first temperature detecting means and heats low-temperature water entering from the lower part of the hot water storage tank and returns it to the upper part of the hot water storage tank;
A fourth temperature detecting means for detecting a temperature of water entering the heat pump unit from a lower part of the hot water storage tank;
Auxiliary heating means that operates based on the detected water temperature of the fourth temperature detection means to heat the water in the hot water storage tank;
With
When the detected water temperature of the fourth temperature detecting means does not exceed a predetermined predetermined incoming water temperature until a predetermined time elapses after the heat pump unit starts the heating operation based on the detected temperature of the first temperature detecting means. A hot water supply apparatus characterized in that the heating operation of the auxiliary heating means is started.
The hot water supply device according to claim 8, wherein the heating operation of the auxiliary heating means is controlled to stop based on the detected water temperature of the fourth temperature detecting means.
The auxiliary heating means is a lower part of the hot water storage tank, and a tank opening part of a water supply pipe for supplying low-temperature water to the lower part of the hot water storage tank and a tank opening part of a connecting pipe for introducing the water in the lower part of the hot water storage tank into the heat pump unit The hot-water supply apparatus of Claim 8 or 9 arrange | positioned more upwards.