JPS63189739A - Heat pump system - Google Patents

Abstract

PURPOSE:To reduce the unpleasant feeling of a user by a method wherein the difference between heated hot water temp. and bathtub water temp. is computed: when the difference is equal to a set value or less, the individual heating operation for the bath is carried out and when the difference exceeds the set value, the simultaneous operations of heating for the bath and space heating are carried out. CONSTITUTION:Indoor units A, B have indoor controllers 42, respectively; when room temp. is detected to be lower than a set temp. by an indoor thermostat 44, a demand signal for space heating operation is output from the controller 42 to an outdoor controller 41. To the bath controller 45 of a bathtub unit C a bath heating operation switch 46 and temp. sensors 38, 39 are connected. The hot water temp. Tin is read in by the sensor 38 placed at a water inlet pipe 24 and heated hot water temp. Tout is read in by the sensor 39 placed at a water outlet pipe 25: when those temp. difference DELTAT exceeds 6 deg.C, the operations of space heating and bath heating are carried out, and when DELTAT is 6 deg.C or less, the space heating operation is forcibly stopped and the operation is switched over to the individual operation of the bath heating. After the individual operation for the bath continues for two minutes, DELTAT is again computed and then the selection for the individual operation for the bath or the simultaneous operations of bath heating and space heating is again carried out.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a heat pump system, and more particularly to a heat pump system having a function of heating bath water using a bath heat exchanger.

(Prior art) As a conventional example of a heat pump system that makes it possible to heat bath water by using a bath heat exchanger, for example, Japanese Patent Laid-Open No. 6
The device described in Japanese Patent No. 0-169045 can be mentioned. This device will be explained based on FIG. 6. In the figure, 51 is a compressor, 52 is an indoor heat exchanger, 53 is an outdoor heat exchanger, 54 is a hot water tank unit, and 55 is a bathtub unit. , each of the above components 5
1 to 55 are connected by a refrigerant circuit 56. The bathtub unit 55 includes a bathtub 57 and a bath heat exchanger 5.
8 and a pump 59 for circulating bath water between the two 57 and 58.

The refrigerant circuit 56 also includes first to fourth electric expansion valves 61.
~ 64, first and second four-way switching valves 65, 66, and first and second solenoid valves 67, 68 are interposed, and these valves 6
By controlling the refrigerant circulation circuits 1 to 68, the refrigerant circulation circuit can be switched. That is, by opening the third and fourth electric expansion valves 63 and 64 and the first hand-held magnetic valve 67, the refrigerant discharged from the compressor l is transferred to the indoor heat exchanger via the second four-way switching valve 66. 52 to the outdoor heat exchanger 53 to heat the room, while opening the first and third electric expansion valves 61, 63 and the first palm valve 67 to reduce the discharge from the compressor 1. The refrigerant is circulated from the bath heat exchanger 58 to the outdoor heat exchanger 53 via the first four-way switching valve 65 to heat the bath.

Although not shown, the above device further includes a room temperature thermometer for detecting the room temperature and a water temperature thermometer for detecting the temperature of the bathtub water. The above-mentioned answers 61 to 64, 67, and 68 require that the heating operation is performed according to the signal from the room temperature thermometer, and the bath heating operation is performed according to the signal from the hot water temperature thermometer when the bath water temperature becomes lower than the set temperature. The operation is controlled. In the above device, control is performed such that when there is an operation request signal from both the room temperature thermostat and the hot water temperature thermostat, the heating operation is not performed and the bath heating operation is performed preferentially. The reason why this switching operation was performed is because if the capacity of the compressor 1 was selected assuming that both of the above operations would be performed at the same time, the equipment itself would become larger and the cost would increase. The reason why the bath heating operation is given priority is because it is considered that a decrease in the water temperature gives the user a greater discomfort than a decrease in the room temperature.

(Problem to be solved by the invention) However, depending on the load condition on the bath side, there may be surplus capacity of the compressor, and a state where heating operation can be performed using this surplus capacity, that is, a situation where heating operation is possible between heating and bath heating. There are cases where simultaneous operations can be performed, and in such cases, the reason why we always give priority to bath heating and decide not to perform heating operation as described above is because heating is not performed without utilizing surplus capacity. This will cause discomfort to the user.

This invention was made in order to solve the above-mentioned conventional drawbacks, and its purpose is to enable simultaneous operation of bath heating and room heating depending on the situation, and to reduce user discomfort. The aim is to provide a heat pump system that can

(Means for Solving the Problems) Therefore, in the heat pump system of the present invention, for example, as shown in FIG. An indoor unit A having a bath heat exchanger 22 and a bathtub unit C having a bath heat exchanger 22 are connected in parallel to each other by refrigerant piping, and the bathtub unit C and bathtub 23 are connected by a water inlet pipe 2.
4 and a water outlet pipe 25 to form a water circulation path, as shown in FIG. a heating operation request signal generating means 44 that generates a heating operation request signal when the bath heating operation request signal is generated; a bath heating operation request signal generating means 47 that detects the temperature of the bath water and generates a bath heating operation request signal when the bath water temperature is less than a reference value; The bathtub 23 is passed through the water outlet pipe 25 from the bathtub unit C.
The heating water temperature detecting means 39 detects the temperature of the heated water returned to the bathtub, and furthermore, when the above-mentioned both operation request signals are issued, the heating water temperature and the bathtub water temperature are checked at predetermined time intervals. Switching operation control for controlling the refrigerant circulation system so that the difference is calculated, and when the calculation result is less than the set value, the bath heating operation is performed alone, and when the calculation result exceeds the set value, the bath heating operation and the space heating operation are performed simultaneously. It has means 45.

(Function) In the heat pump system having the above configuration, when both heating and bath heating operation request signals are output, the temperature of the heated water flowing into the bathtub unit C and the temperature of the bathtub water before flowing into the bathtub unit C are changed. The difference is calculated at predetermined time intervals, and when the result exceeds a set value, heating and bath heating are operated simultaneously. In other words, if the bathtub unit C has sufficient bath heating capacity, this bathtub unit C
A large amount of heat is given to the hot water flowing through the water, resulting in a large temperature difference between before it flows in and after it flows out. Therefore, by comparing with the set value, if it is determined that there is a surplus in the bath heating capacity, heating operation is also performed at the same time. If the above temperature difference becomes below the set value due to the bath heating capacity being diverted to heating for heating during simultaneous operation, the bath heating will be operated independently for the next predetermined time interval. It is done. In this way, bath heating is given priority, and heating operation is also performed depending on the surplus heating capacity, so heating operation becomes more frequent than before, resulting in user discomfort. This can reduce the

(Example) Next, a specific example of the heat pump system of the present invention will be described in detail with reference to the drawings.

First, a refrigerant circuit diagram is shown in FIG. 2, and as shown in the figure, this device has an outdoor unit X, two indoor units A and B, and a bathtub unit C. The outdoor unit X has a compressor 1, and the discharge piping 2 of this compressor 1
and the suction pipe 3 are each connected to a four-way switching valve 4. Note that an accumulator 6 is interposed in the suction pipe 3. The four-way switching valve 4 has a first gas pipe 7 and a second gas pipe 7.
Although the first gas pipe 7 is connected to the gas pipe 8,
It is connected to an outdoor heat exchanger 9 equipped with an outdoor fan 18, and the second gas pipe 8 is connected to a header 10. Further, a first liquid pipe 11 is connected to the outdoor heat exchanger 9, and this first liquid pipe 11 is connected to a liquid receiver 12, and a first electric expansion valve 13 is interposed in the middle thereof. It is set up. One end of a second liquid pipe 14 is connected to the liquid receiver 12, but there are three pipes between the other end of the second liquid pipe 14 and the header 10 in the case of the figure. branch refrigerant pipes 15 to 17 are connected thereto. Two pipes 15 and 16 of the branched refrigerant pipes are connected to the indoor unit A, respectively.
, B, and the remaining refrigerant pipe 17 is connected to the bathtub unit C. Each of the above indoor units ASB is illustrated for only one indoor unit A, but the indoor heat exchanger 1
9 and an indoor fan 20. The bathtub unit C has a bath heat exchanger 22, a water inlet pipe 24 that connects the bath heat exchanger 22 to the bathtub 23, and a water outlet pipe 25. A pump 26 is interposed in the water inlet pipe 24, and this pump 26
By operating the bathtub 23, the hot water in the bathtub 23 is circulated through the bath heat exchanger 22. In each of the branch refrigerant pipes 15 to 17, second electric expansion valves 27 to 29 are respectively provided at positions on the liquid pipe 14 side.

Further, a gas shut-off valve 36 and a liquid shut-off valve 37 are interposed in the second gas pipe 8 and the second liquid pipe 14, respectively.

FIG. 3 shows a schematic diagram of the structure of the bathtub unit C. The bath heat exchanger 22 is composed of a double pipe with leakage detection, and the pump 26 is turned off during bath heating operation. As a result of the operation, hot water from the bathtub is transferred from the water inlet pipe 24 to the bath heat exchanger 2, as shown by the dashed line in the figure.
2 to the water outlet pipe 25, while the refrigerant circulates through the refrigerant pipe 17 in the direction of the solid arrow in the figure. At this time, the flow directions inside the bath heat exchanger 22 are opposite to each other, and therefore the first temperature sensor is attached to the water inlet pipe 24 near the inlet of the bath heat exchanger 22. 38 detects the temperature of the water in the bathtub, and this detected temperature also becomes a value that can approximate the condensation temperature of the refrigerant in the bath heat exchanger 22. Further, the temperature of the heated hot water flowing through the bath heat exchanger 22 is detected by a second temperature sensor 39 attached to the water outlet pipe 25 and serving as heated water temperature detecting means.

In the heat pump system described above, when performing heating operation, the second electric expansion valve 29 on the bathtub unit C side
is set to the stop opening (an opening that allows a small amount of refrigerant to flow in order to prevent liquid accumulation in the bath heat exchanger 22, the same applies hereinafter), and other necessary second electric expansion valves 27 .2
8 is the control opening for controlling the degree of subcooling of the indoor heat exchangers 19, 19, and the refrigerant discharged from the compressor 1 is
The heat is circulated from each of the indoor heat exchangers 19 to the outdoor heat exchanger 9 via the four-way switching valve 4 in the direction shown by the solid arrow in the figure. In this case, the first electric expansion valve 13 is set to a controlled opening degree that controls the degree of superheating of the outdoor heat exchanger 9. In addition, when performing bath heating operation, the second electric expansion valves on the indoor units A and B sides are set to the stop opening at 27.2 days, and
The second electric expansion valve 29 and the first electric expansion valve 13 on the bathtub unit C side are controlled to the same opening degree as above, and the refrigerant discharged from the compressor 1 is transferred to the outdoor heat from the bath heat exchanger 22 in the same manner as above. Circulate to exchanger 9. In addition, in the case of simultaneous operation of bath heating and space heating, the necessary opening degrees of the second electric expansion valves 27 and 28 and the second electric expansion valve 29 may be controlled. In the cooling operation and the bath cooling operation, the four-way switching valve 4 is switched to direct the refrigerant discharged from the compressor 1 as indicated by the broken line arrow in FIG.
Contrary to the above, from the outdoor heat exchanger 9 to the indoor heat exchanger 19.
This is done by circulating the water to the heat exchanger 19 and the bath heat exchanger 22. In this case, the first electric expansion valve 13 is fully opened, and the second electric expansion valves 27 to 29 control the degree of superheating of the evaporative refrigerant.

Next, the operation control circuit of the heat pump system will be explained based on FIG. 4, and the following explanation will be made regarding heating operation and bath heating operation.

As shown in the figure, the outdoor unit
It has a function of controlling operation modes such as heating operation, bath heating operation, simultaneous heating and bath heating operation, etc.

On the other hand, the indoor units A and B each have an indoor control device 42, and a heating operation switch 43 and an indoor thermostat 44 serving as heating operation request signal generation means are connected to these indoor control devices 42, respectively. ing. Then, when the heating operation switch 43 is ON, the indoor thermostat 44 detects that the room temperature has become lower than the set temperature, and a heating operation request signal is generated, the indoor control device 42 sends the outdoor control device 41 Then, a heating operation request signal is output. The outdoor control device 41 and the indoor control device 42
A normally closed contact MR50-1 of a switching relay MR50, which will be described later, is interposed in the signal line for exchanging signals between the two.

Next, the bathtub unit C has a bath control device 45 as shown in FIG. A first temperature sensor 38 and a second temperature sensor 39 are connected. Note that the first temperature sensor 38 also constitutes a hot water temperature detecting section of a hot water temperature thermometer 47 which is a means for generating a bath heating operation request signal, and the detected hot water temperature and set temperature by this first temperature sensor 38 are When the temperature is lower than , a hot water temperature thermo signal that is turned ON is generated as a bath heating operation request signal. When the bath heating operation switch 46 is ON and the hot water temperature thermostat 47 is generating an ON hot water temperature thermo signal, a bath heating operation request signal is output from the bath control device 45 to the outdoor control device 41. be done.

Further, in the bath control device 45, the first and second
Based on the signals from the temperature sensors 38 and 39 and the hot water temperature thermometer 47, ON-OFF control of the pump 26 and the switching relay MR50 is performed as described later.

FIG. 5 shows a flowchart of bath heating operation control in the bath control device 45.

As shown in the figure, when the bath heating operation switch 46 is turned on, the pump 26 is started in step S1, and the pump 26 continues to operate for one minute. At this time, the hot water in the bathtub 23 is circulated through the bath heat exchanger 22, and as a result, the hot water in the bathtub 23 is agitated, and the temperature of the water in the bathtub 23 is made uniform. After one minute has passed, in step S2,
The first temperature sensor 38 attached to the water inlet pipe 24
The hot water temperature Tin corresponding to the bath water temperature detected in step S3 is read, and in step S3 it is determined based on the hot water temperature thermo signal whether the bath water temperature Tin is lower than the set temperature. When the hot water temperature thermo signal is ON, that is, when the detected bath water temperature Tin is lower than the set temperature, the process moves to step S4, and the bath heating operation request signal is sent to the outdoor control device 4.
Send to 1. As a result, the outdoor control device 41 starts circulating the refrigerant to the bath heat exchanger 22, and the bath water is heated. Next, in step S5, the elapsed time is judged, and the processes of steps 32 to S4 are repeated for 2 minutes while the pump remains in operation. That is, while heating the bathtub water, the bathtub water temperature Tin is sequentially read and compared with the set temperature. During this time, if a heating operation request signal is also output from the indoor control device 42, simultaneous operation will be performed.

If it is determined in step S5 that 2 minutes have elapsed, the process proceeds to step S6, where the heated water temperature To detected by the second temperature sensor 39 attached to the water outlet pipe 25 is
ut is read, and then in step S7, the difference from the bathtub water temperature Tin read immediately before, Tout-Tin
is calculated, and if the result exceeds 6°C, the switching relay MR50 is continued in the OFF operating state in step S8, and on the other hand, if the result is below 6°C, the switching relay MR50 is turned ON in step S9. The process then switches to the state and returns to step S2. Therefore, during the 2-minute repeated processing period described above in steps 32 to S5 that are performed next, the heated water temperature T.

If the difference ΔT between ut and the bath water temperature Tin exceeds 6°C, the bath will be heated in a state where heating can be operated simultaneously in the same way as above, but if ΔT is 6°C or less In that case, due to MR50 being activated,
Normally closed contact M of the switching relay MR50 interposed in the signal transmission line between the outdoor control device 41 and the indoor control device 42
R50-1 is opened. For this reason, the indoor control device 42
transmission of a heating operation request signal from to the outdoor control device 41;
Further, transmission in the opposite direction is also no longer possible. Therefore, if heating and bath heating were being operated at the same time, the heating is forcibly stopped and the bath heating is switched to independent operation. That is, the outdoor control device 41 switches to refrigerant circulation for bath heating alone, and the indoor control device 42 stops the indoor fan 20.

After continuing the bath solo operation as described above for 2 minutes, Tout is read again (step S6) and ΔT is calculated (step S7), and based on the calculation results, the next two steps are performed.
A selection is made again as to whether the bath should be operated alone or in a state where it can be operated simultaneously with heating (steps S8 and S9).

In this way, for one minute after the pump 26 is started and after the first bath heating is performed for two minutes, the temperature is calculated based on the difference ΔT between the bathtub water temperature Tin and the heated water temperature Tout, which is detected and calculated every two minutes. Therefore, the bath is switched between single operation and simultaneous operation with heating operation. Therefore, in the case where the heating operation request signal is constantly output, for example, the bath single operation is continued when ΔT is 6°C or less, while the simultaneous operation is continued when ΔT exceeds 6°C. It happens.

Such switching control based on ΔT is performed for the following reasons. For example, a water pipe with an inner diameter of 11++ m in the bath heat exchanger 22 has a flow rate of 1.0 m/s to 1.5 m/s.
Hot water is circulated at s, and at this time, the inlet of the bath heat exchanger 22,
Assuming that the difference ΔT in hot water temperature at the outlet is 6°C, the amount of heat given to the circulating hot water at this time is 2052 Kcal/
H~3096Kcal/H, which is judged to be sufficiently satisfactory as a bath heating ability. If ΔT exceeds 6° C., it is determined that the bath heating capacity is surplus and that it is possible to reduce the amount of refrigerant flowing through the bath heat exchanger 22 to some extent. Therefore, when there is a request for heating operation, the refrigerant is also diverted to the indoor heat exchanger 19 to perform simultaneous operation with heating. As a result, conventionally, heating operation was primarily stopped when heating a bath, but in the above embodiment, the frequency of heating operation during bath heating can be reduced without compromising the comfort of the bath user. This can reduce the discomfort of heating users.

In FIG. 5, when the bathtub water temperature Tin reaches the set temperature while repeating steps 82 to S9, the process moves from step S3 to step SIO,
Stopping pump 26 (step 510), switching relay MR
50 OFF operation (step 5ll), outdoor control device 4
1 (Step 512), and the above state continues for 10 minutes (Step S1).
3) After that, the process from step S1 described above is resumed. The bath heating is stopped during the above 10 minutes, and if the heating operation request signal is output from the indoor control device 42, the heating operation is continued or restarted. Once the water temperature has reached the set temperature, it is determined that the drop in water temperature is extremely slow, and therefore
During the 0 minute period, priority is given to heating operation to recover the room temperature.

As mentioned above, in the above heat pump system,
The difference between the bathtub water temperature, which varies depending on the heating capacity of the bath heat exchanger 22, and the heated water temperature after flowing through the bath heat exchanger 22 is compared with a standard value of 6°C, and as a result, the bath is heated sufficiently. Since it is possible to perform simultaneous operation of bath heating and space heating when there is capacity, the frequency of heating operation becomes higher compared to the conventional case where heating operation is primarily stopped. This will reduce the discomfort of the heating user. In particular, when the bathtub water temperature becomes high and approaches the set temperature, there is a high probability that there will be a surplus in the bath heating capacity, that is, the capacity of the compressor 1, and that the heating operation will be possible with this surplus capacity. Therefore, it is a compressor.”
This means that the capacity of the air conditioner can be fully utilized, making a significant contribution to comfortable air conditioning. In addition, the capacity of the compressor 1 can be selected to be excessively large assuming simultaneous operation of heating operation and bath heating, and it is possible to provide comfort to the heating user as well as the bath user. It is also possible to downsize the device and reduce costs.

In the above description, the heating operation request signal generating means is the indoor thermometer 44, the bath heating operation request signal generating means is the hot water temperature thermometer 47, the heating water temperature detecting means is the second temperature sensor 39, and the switching operation control means 45. Steps 52 to S in Figure 5
9, but it is also possible to use other components having similar functions. In addition, it is of course possible to change the reference value for comparing the difference between the bathtub water temperature and the heated water temperature and the set time of each timer set in the above embodiment as appropriate depending on the installation and usage conditions of the device. be.

(Effects of the Invention) In the heat pump system of the present invention, when the heating and bath heating operation request signals are output as described above, the bath heating capacity is detected, and the bath heating capacity is determined to be higher than the reference value. In some cases, heating and bath heating are operated simultaneously, which means that the heating operation is more frequent than in the past, reducing user discomfort and providing comfortable air conditioning. Become.

[Brief explanation of the drawing]

1 to 5 show examples of the heat pump system of the present invention, in which FIG. 1 is a functional system diagram, FIG. 2 is a refrigerant circuit diagram, and FIG. 3 is a schematic diagram showing the configuration of a bathtub unit. FIG. 4 is a circuit diagram of the control system, FIG. 5 is a flowchart of an operation control method during bath heating operation, and FIG. 6 is a refrigerant circuit diagram of a conventional example. X...Outdoor unit, A...Indoor unit, C...
- Bathtub unit, l... Compressor, 9... Outdoor heat exchanger, 19... Indoor heat exchanger, 22... Bath heat exchanger, 23... Bathtub, 24... Water Inlet pipe for use, 25...
・Water outlet pipe, 39... Second temperature sensor (heated water temperature detection means), 44... Indoor thermometer (heating operation request signal generation means), 45... Bath control device (switching operation control means) ), 47...Bath water temperature thermometer (bath heating operation request signal generation means).

Claims (1)

[Claims] 1. An indoor unit (A) having an indoor heat exchanger (19) and a bath heat exchanger (22) are added to the outdoor unit (X) having a compressor (1) and an outdoor heat exchanger (9). The bathtub unit (C) having the bathtub unit (C) is connected in parallel with each other by refrigerant piping, and the bathtub unit (C) and the bathtub (23)
This is a heat pump system in which a water circulation path is configured by connecting a water inlet pipe (24) and a water outlet pipe (25) with a water inlet pipe (24) and a water outlet pipe (25). A heating operation request signal generating means (44) that issues a heating operation request signal at a certain time, and a bath heating operation request signal that detects the temperature of the bathtub water and issues a bath heating operation request signal when the bathtub water temperature is less than a reference value. Generating means (
47) and a water outlet pipe (2) from the bathtub unit (C).
5) and a heated water temperature detection means (39) for detecting the temperature of the heated water returned to the bathtub (23) through The difference between the heating water temperature and the bathtub water temperature is calculated, and if the calculation result is less than the set value, the bath heating operation is performed alone, and when it exceeds the set value, the refrigerant circulation is performed to perform the bath heating operation and heating operation simultaneously. A heat pump system characterized by having a switching operation control means (45) for controlling a system.