JPH02126051A - Operation control method for heat pump type hot water feed device - Google Patents

Abstract

PURPOSE:To enable detection of disturbance of stratification in a hot water storage tank for some reason and to prevent the increase of the pressure of refrigerant gas flowing through a heat exchanger for the feed of hot water by a method wherein when the temperature of hot water at a low temperature hot water layer is increased, the flow of refrigerant gas to the heat exchanger for the feed of hot water is stopped. CONSTITUTION:The detecting result of a hot water temperature sensor 45c in a hot water storage tank 28 is compared with the detecting result of a hot water temperature sensor 45b therein. When the temperature of a lower part is higher than usually considered temperature, it is indicated that a layer in the tank is disturbed for some reason. When the abnormality is detected, a solenoid valve on the first distributing passage side is closed, and the flow of refrigerant gas to a position on the part of the heat exchanger for the feed of hot water is stopped. This constitution causes the pressure of a refrigerant flowing through the heat exchanger for the feed of hot water, resulting in prevention of the failure in operation of a device, e.g., compressors. From a detecting value of a flow rate sensor, a necessary amount of feed hot water is calculated. Comparison with hot water feed capacity provided only by an exhaust heat recovery device is effected, and when hot water feed capacity is insufficient, an auxiliary heat source 32 is driven, and the temperature of hot water in the hot water storage tank 28 is also increased by means of the auxiliary heat source 32.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to a method for controlling the operation of a water heater that uses a heat pump to supply hot water and air condition the water.

Conventional technology A heat exchanger for hot water supply is installed in a heat pump device for air conditioning.
Devices that also supply hot water have been known for some time. In such a hot water supply device, hot water that has been heat exchanged by a hot water supply heat exchanger is stored in a hot water storage tank, and is taken out from the hot water storage tank to a take-out side such as a hot water tank (Utility Model Publication No. 57-35809). (See public road). In order to maintain the hot water in this hot water tank at a predetermined temperature,
The hot water in the hot water supply tank is circulated to the hot water supply heat exchanger side to raise its temperature.

In a hot water supply system equipped with a hot water storage tank as described above, the inside of the hot water storage tank has a two-layer structure consisting of a high temperature hot water layer on the upper side and a low temperature hot water layer on the lower side, and the hot water is taken out to the drain side from the high temperature hot water layer side. It has been considered to circulate hot water from the low-temperature hot water layer to the hot water supply heat exchanger side and supply it to the high-temperature hot water layer. By doing this, normally only a portion of the hot water in the tank is maintained at the necessary high temperature, and the high temperature is increased only as the amount used increases or when the amount used is expected to increase. Since it is sufficient to increase the amount of hot water supplied to the hot water layer, there is an advantage that the entire apparatus can be operated economically.

Problems to be Solved by the Invention Therefore, when a hot water storage tank with a two-layer structure is used, if the layers are disturbed, the above operation becomes impossible, and high-temperature hot water cannot be taken out. Furthermore, since the heat pump circuit is designed to raise the temperature of the hot water in the lower low-temperature layer to a predetermined temperature, even if the layers are disturbed and the high-temperature and low-temperature layers are turned upside down, in case of,
The high-temperature hot water is circulated to the hot water supply heat exchanger side, and the pressure of the refrigerant gas passing through the hot water supply heat exchanger increases, which may cause a failure of the heat pump circuit.

Furthermore, in a heat pump device, hot water heated by a heat exchanger for hot water supply is raised in temperature using cooling water from a compressor driving engine, and then supplied to the hot water storage tank. At startup, since this cooling water temperature is low, the water temperature cannot be raised to the specified temperature, and low A? There is an inconvenience that X is supplied.

This invention was made with the aim of solving these problems in heat pump type hot water supply systems.

Means for Solving the Problems And, in order to solve the above problems, the first part of this application
In the invention, the hot water storage tank has a 2N structure with one high-temperature layer on the upper side and a low-temperature layer on the lower side, and hot water heated by heat exchange with refrigerant gas passing through a hot water supply heat exchanger is transferred to the high-temperature layer. In a heat pump circuit that circulates hot water from a low-temperature layer to a heat exchanger for hot water supply, the temperature of the hot water in the low-temperature layer is detected, and when the temperature of the hot water exceeds a certain temperature, the heat exchanger for hot water supply It is characterized by stopping the flow of refrigerant gas to the container.

In addition, in the second invention of this application, the inside of the hot water storage tank has a two-layer structure consisting of a high-temperature hot water layer on the upper side and a low-temperature hot water layer on the lower side, and heat exchange with refrigerant gas passing through a heat exchanger for hot water supply is provided. In a heat pump circuit that supplies hot water heated by It is characterized by restricting the flow rate of refrigerant gas passing through the heat exchanger for hot water supply when the temperature exceeds a certain temperature, and further stopping the flow of refrigerant gas to the heat exchanger for hot water supply when the temperature exceeds a predetermined temperature higher than that. do.

Furthermore, in the third invention of this application, the refrigerant discharged from the compressor is circulated to the hot water supply heat exchanger, the water side heat exchanger, and the air side heat exchanger, and is heated by the hot water supply heat exchanger. In a heat pump circuit for hot water supply and air conditioning, which heats hot water by further heat exchange with cooling water of a compressor driving engine, when hot water supply and air conditioning are started, only air conditioning operation is performed until the temperature of the cooling water reaches a predetermined temperature. After that, the system shifts to hot water supply and air conditioning operation.

Effect According to the first configuration of the present invention, when the temperature of the low-temperature hot water layer increases, the flow of refrigerant gas to the hot water supply heat exchanger is stopped. It is possible to detect disturbances due to this reason, and to prevent the pressure of the refrigerant gas passing through the hot water supply heat exchanger from increasing.

In addition, in the configuration of the second invention, in order to perform the above-mentioned control more finely, the flow of refrigerant gas to the hot water supply heat exchanger side is restricted in advance before stopping the flow of refrigerant gas. This prevents the pressure of the refrigerant gas from rising to a dangerous pressure.

Furthermore, in the third configuration of the present invention, when the cooling water temperature of the compressor driving engine is low, the heat pump circuit is operated only in air conditioning operation, and only when the cooling water temperature rises is the heat pump circuit operated on the hot water heat exchanger side. A refrigerant gas is supplied to the hot water supply operation.

The eighth embodiment is a circuit diagram of a pump device used in an embodiment of the present invention. In the figure, (1) is a compressor driven by an engine (2). The discharge side passage of this compressor (1) is a first distribution passage (3).
) and a second distribution passage (4), one of which is divided into a first distribution passage (4) and a second distribution passage (4).
The distribution passage (3) is connected to the hot water supply heat exchanger (6) via the first solenoid valve (5). A passage (7) on the outlet side of this hot water supply heat exchanger (6) is connected to a cash register/<- tank (8). Said second distribution channel (4) is connected to one boat of a four-way valve (10) via a second solenoid valve (9). One other boat (b) is connected via a passage (11) to a water side heat exchanger (12), with a passage (13) connected to the opposite side of this water side heat exchanger (12). , is connected to the receiver tank (8) via an expansion valve (14), a magnetic valve (15), etc.

Furthermore, the boat (C) of the four-way valve (10) is connected to the passage (16).
It is connected to the air side heat exchanger (17) via the passage (16), and another solenoid valve (18) is provided in the middle of this passage (16).

A passage (1) connected to the opposite side of the air side heat exchanger (17)
9) is likewise connected to the receiver tank (8) via a solenoid valve (20). Moreover, this air side heat exchanger (17) is connected to another passage (
22) is also connected to the receiver tank (8). Furthermore, a passage (46) branched from the passage (16).
) is connected to an accumulator (47), from which air is drawn into the compressor (1).

(25) is a cooling water circuit for the engine (2), and an exhaust heat recovery device (2G) is provided in the middle of this cooling water circuit (25). The hot water warmed by heat exchange with the hot water supply heat exchanger (6) is heated in the exhaust heat recovery device (26) by heat exchange with the cooling water, and then passed through the hot water supply passage (2).
7) is supplied to the hot water storage tank (2B) side. The hot water in the hot water storage tank (28) is circulated to the hot water supply heat exchanger (6) through a return passage (29).

Hot water stored in the hot water storage tank (28) is taken out to the side (31) through a hot water take-out passage (30).

In addition, in order to supplement the capacity of the heat pump circuit, hot water in the hot water storage tank (2 days) is used as boiler or other auxiliary heat source (32 days).
) side is connected to an auxiliary heat source circuit (32).

On the other hand, the water side heat exchanger (12) is provided with a cold/hot water circuit (35) that connects an air conditioning cold/hot water tank (34) and the water side heat exchanger (12). The hot water in the cold/hot water tank (34) is circulated toward the indoor air conditioning load device (37) by the cold/hot water supply circuit (36).

Similarly, in order to supplement the heat exchange capacity of the water side heat exchanger (12), the hot water in the cold/hot water tank (34) is used as the auxiliary heat 11a.
An auxiliary heat source circuit (38) for circulating to the (3B) side is provided.

FIG. 9 shows the structure inside the hot water storage tank (28), in which hot water from the hot water supply heat exchanger (6) side and auxiliary heat a (32) are stored. Hot water from the side is introduced from the upper side of the hot water storage tank (28), and circulating hot water is also taken out from the bottom of the tank to the auxiliary heat source (32) and hot water supply heat exchanger (6) side, and make-up water is By forming the inlet (41) at the bottom of the tank, a stratified state consisting of a high-temperature hot water layer (42) on the upper side and a low-temperature hot water layer (43) on the lower side is maintained. And the take-out passage (30) to the said tongue (31) (31) side.
By providing an outlet to the hot water layer (42) on the side of the hot water layer (42), the hot water can be taken out and used at all times. In order to maintain this stratified state,
At positions near the top and bottom of the hot water storage tank (28), there are rectifying plates (44) made of perforated plates that prevent the hot water in the tank from being disturbed when hot water flows into or out of the tank.
) (44) is provided. Furthermore, this hot water storage tank (2 days) is equipped with a large number of thermistors (45a) (45b)... as hot water temperature detection means for measuring the hot water temperature at each position in the vertical direction within this hot water storage tank (28). are provided at appropriate intervals.

In the above-described heat pump circuit, the refrigerant discharged from the compressor (1) is in a state where the solenoid valves (5) and (9) of the first distribution passage (3) and the second distribution passage (4) are open. A portion of the water supply heat exchanger (
6), and after warming the water for hot water supply by heat dissipation during condensation, the liquefied gas flows to the receiver tank (8) side. When the water-side heat exchanger (12) is used for cooling, the refrigerant flowing to the second distribution passage (4) first passes from the four-way valve (10) through the illumination passage (16) to generate heat on the air side. It flows into the exchanger (17). Then, the refrigerant that has released heat due to heat radiation during condensation in the air side heat exchanger (17) enters the receiver tank (8) side and is combined with the refrigerant from the hot water supply heat exchanger (6) side. They join together, pass through the passage (13), are depressurized by the fat expansion valve (14), pass through the water-side heat exchanger (12), flow from the four-way valve (10) to the accumulator (47) side, and then flow into the compressor. (1) Return to the side.

When hot water is not being supplied, the solenoid valve (5) in the first distribution passage (3) flowing toward the hot water supply heat exchanger (6) is closed, and the refrigerant gas is passed through the air side heat exchanger (17). ) and the water side heat exchanger (12), and is used only for air conditioning. Note that during heating, the flow of refrigerant gas circulating to the air side heat exchanger (17) and water side heat exchanger (12) is in opposite directions. When performing both cooling and hot water supply, if the hot water supply heat exchanger (6) has low hot water supply capacity or heat exchange capacity, the solenoid valve (9) on the second distribution passage (4) side
), close the hot water supply heat exchanger (6) and the water side heat exchanger (12).
), that is, by using the hot water heat exchanger (6) as a condenser and the water side heat exchanger (12) as the other evaporator, refrigerant is supplied to the air side heat exchanger (17) side. Hot water can be supplied and cooled without circulation. In this state, the entire amount of the refrigerant gas flows toward the hot water supply heat exchanger (6), so the refrigerant flow rate is maximum.

Next, a specific method of controlling the heat pump hot water supply circuit will be explained.

FIG. 1 is a block diagram of a control device of the present invention. (51) is a controller, and as this controller (51), for example, a microcomputer is used. Each hot water temperature sensor (45a>
(45b)... is detected by the controller (51).
). Furthermore, a detection signal from a hot water amount sensor (53) that detects the amount of hot water flowing out from the hot water storage tank (28) is also input to this controller (51). The control π signal from the controller (51)
First and second solenoid valves (5) in refrigerant distribution passages (3) and (4)
(9) side to control the opening and closing of these solenoid valves (5) and (9). Further, in order to drive the auxiliary heat source (32), a control signal is also output to the auxiliary heat source driving device (32a).

FIG. 2 is a flowchart of a control procedure for performing n on the operation side of the heat pump device according to the first invention of this application. First, each hot water temperature detection sensor (45a
)<45b)... Step SL), then each of these sensors (45a
) (45b)... The hot water temperatures are compared based on the signals from (step S2). If the hot water temperature in the hot water storage tank (2B) is higher at the lower side than the upper side at any one location, for example, the hot water temperature sensor (4
5c) detection result and the @ temperature sensor above it (45b)
), and if the lower temperature is higher than expected, for some reason, the tank (28>
Indicates that the inner layers have been disturbed. Through this, it is determined whether the hot water temperature in the hot water storage tank (28) is normally distributed (S3), and if it is normal, such a determination is repeated. In this case, the standard for abnormality judgment is determined by, for example, whether the upper side is 10°C or more higher than the lower side.
5) to stop the flow of refrigerant gas to the hot water supply heat exchanger (6) side. As a result, the temperature of the hot water flowing to the hot water storage tank (28) will be raised only by the exhaust heat recovery device (26) (S4). ) There may be cases where the temperature on the high-temperature hot water layer (42) side in the hot water layer (42) is not sufficient. Therefore, as a next step, for example, calculate the required amount of hot water supply based on the detected value of the flow rate sensor (53) (S5), and compare the required amount of hot water with the hot water supply capacity only by the waste heat recovery device (26) as described above. A comparison is made (S6), and if the hot water supply capacity is insufficient, the auxiliary heat source (32) is driven to generate this auxiliary heat g (
32) also outputs a signal to raise the temperature of the hot water in the hot water storage tank (28) (S7).

FIGS. 3 and 4 are block diagrams and flowcharts of control procedures for controlling operation according to the second aspect of the present invention.

First, as shown in FIG. 3, the controller (51)
, there is a return hot water temperature sensor (5) installed in the return passage (29) from the hot water storage tank (2B) to the hot water supply heat exchanger (6) side.
The detection signal of 4) is inputted.

Then, the detection signal from this sensor (54) is
L, (S L), then determine whether the detected temperature is within the safe water temperature range or higher (
S2). If the temperature is also lower than the predetermined safe water temperature ts, the first solenoid valve (5) is opened and the second
The solenoid valve (9) is closed, and the refrigerant is circulated only between the hot water supply heat exchanger (6) and the water side heat exchanger (12), and the entire amount flows to the hot water supply heat exchanger (6) side (S3 ), if the water temperature t is higher than the safe water temperature ts, it is further determined whether the water temperature t is greater than the caution water temperature range td, which is the stage before the dangerous state (S4), and if it is in the caution water temperature range for,
A control signal that also opens the second electromagnetic valve (9) is output, and a part of the refrigerant gas also flows to the air side heat exchanger (17) side, so that it is sent to the hot water supply heat exchanger (6). Limit the flow rate (35
), and if the water temperature t is higher than the caution water temperature, that is, in the dangerous water temperature range, the solenoid valve (5) in the first refrigerant distribution passage (3) is closed in the same way as described above, and the hot water supply is thereby stopped. At the same time, the solenoid valve (9) in the second refrigerant distribution passage (4) is opened to transfer heat from the water side heat exchanger (12) to the air side heat exchanger (12). The refrigerant is circulated only between the exchangers (17) to perform cooling only operation (S
6) As a result, the temperature of the hot water flowing into the hot water storage tank (28) is increased only by the exhaust heat recovery device (26).

Further, in this second embodiment as well, control for driving the auxiliary heat 'rA (32) may be added in the same manner as described above.

Figures 5 and 6 show the start-up system for hot water supply, cooling, or heating. 1 is a block diagram and a flowchart for performing I. As shown in FIG. 5, the controller (51) includes the engine cooling water temperature sensor (52).
and the detection signal of the tank water amount detection sensor (55) are input. In the sixth time, when the startup mode starts, the controller (51) closes the solenoid valve (5) in the first refrigerant distribution passage (3), and closes the solenoid valve (5) in the second refrigerant distribution passage (4).
A signal is output to open the solenoid valve (9) inside, thereby transferring the refrigerant to the water side heat exchanger (12) and the air side heat exchanger (12).
7) The engine cooling water is circulated only between and performs air conditioning operation (step 31). Next, the engine cooling water is circulated between /! A signal from the S detection sensor (52) is input (S2), and it is determined whether the cooling water temperature is a predetermined temperature, for example, 60° C. or higher (S3). If the water temperature has not reached 60°C, the above operation is repeated, and when it reaches 60°C, a control signal is output to open the first solenoid valve (5) to switch to normal hot water supply operation ( 34) Next, the water amount detection signal is further input (S5), and it is determined whether hot water has been supplied to the hot water storage tank (28) until it is full (S6). Then, repeat this operation until the hot water storage tank (2
8) Supply hot water to the side. When the tank is full, a control signal is output to close the first electromagnetic valve (5) and only air conditioning operation is performed. Supply only hot water (
S7), and further determines whether to continue driving S8
), if continuation is not necessary, the operation is stopped; if continuation is necessary, the operations from step S7 are repeated. FIG. 7 shows a time chart of changes in hot water supply amount and hot water storage amount due to changes in engine cooling water temperature from startup to continued operation.

Effects of the Invention As described above, according to the present invention, when hot water is circulated to the hot water supply heat exchanger side due to disturbance of the layers in the hot water storage tank, etc. By limiting the circulation of refrigerant to or stopping the amount of circulation,
This increases the pressure of the refrigerant passing through the heat exchanger for hot water supply, and has the effect of preventing failures of equipment such as the compressor. In addition, as it is possible to detect layer disturbances as described above, by quickly taking countermeasures based on this, it is possible to prevent low-temperature hot water from being taken out to the extraction side, or to eliminate the problem at an early stage. There is an effect that it can be done. In addition, in the third invention of this application, when starting the hot water supply/air conditioning mode, the flow of refrigerant to the hot water supply heat exchanger side is stopped until the cooling water temperature reaches a certain temperature or higher, so that the flow of refrigerant to the hot water storage tank side is stopped. This has the effect of eliminating the inconvenience of being supplied with low-temperature hot water.

[Brief explanation of drawings]

FIG. 1 is a program diagram of a control device showing a first embodiment of the present invention, FIG. 2 is a flowchart of the control procedure, and FIG. FIG. 4 is a flow chart of the control device shown in FIG. 4, FIG. 5 is a block diagram of the control device showing the third embodiment of the present invention, and FIG. Chart, Figure 7 is a time chart showing changes in engine cooling water temperature, hot water supply amount, etc. from startup to normal hot water supply operation, Figure 8 is a circuit diagram of the heat pump device, and Figure 9 is a hot water storage tank. It is an enlarged view of a part. (1)...compressor, (2)...engine, (
5)... 1st ii magnetic valve, (6)... hot water supply heat exchanger, (9)... second solenoid valve, (12)... water side heat exchanger, (17)...・Air side heat exchanger, (25)...Engine cooling water circuit, (26)...Exhaust heat recovery device, (28)...Hot water storage tank, (42)...High temperature hot water layer, (43)... )...low temperature'45
N, (45a) to (45e)... Hot water temperature detection sensor patent applicant Yanmar Diesel Co., Ltd. agent patent attorney Hisayuki Tarumoto Startup F48 t

Claims (1)

[Claims] 1. The inside of the hot water storage tank has a two-layer structure with a high temperature hot water layer in the upper side and a low temperature hot water layer in the lower side, and hot water is heated by heat exchange with refrigerant gas passing through a hot water supply heat exchanger. In a heat pump circuit that supplies hot water to a high-temperature layer and circulates hot water in a low-temperature layer to a heat exchanger for hot water supply, the temperature of the hot water in the low-temperature layer is detected and the temperature of the hot water exceeds a certain temperature. A method for controlling the operation of a heat pump type water heater, characterized in that the flow of refrigerant gas to a heat exchanger for hot water supply is stopped. 2. The hot water storage tank has a two-layer structure with a high-temperature hot water layer at the top and a low-temperature hot water layer at the bottom, and hot water heated by heat exchange with refrigerant gas passing through the hot water supply heat exchanger is supplied to the high-temperature hot water layer. In a heat pump circuit configured to circulate hot water in a low-temperature layer to a heat exchanger for hot water supply, the temperature of the hot water in the low-temperature layer is detected, and when the temperature of the hot water exceeds a certain temperature, the heat exchanger for hot water supply is activated. A method for controlling the operation of a heat pump hot water supply device, the method comprising: limiting the flow rate of refrigerant gas passing through the heat pump, and further stopping the flow of the refrigerant gas to a heat exchanger for hot water supply when the temperature reaches a predetermined temperature higher than the predetermined temperature. 3. The refrigerant discharged from the compressor is circulated to the hot water supply heat exchanger, the water side heat exchanger, and the air side heat exchanger, and the hot water heated by the hot water supply heat exchanger is further circulated to the compressor driving engine. In a heat pump circuit for hot water supply and air conditioning, which raises the temperature by heat exchange with cooling water, when hot water supply and air conditioning are started, only air conditioning operation is performed until the temperature of the cooling water reaches a predetermined temperature, and then the hot water supply and air conditioning operation is started. A method for controlling the operation of a heat pump water heater, characterized in that: