JPH1078266A - Control method for hydrothermal source air conditioning device and hydrauthermal source air conditioning device having protective function - Google Patents

Abstract

PROBLEM TO BE SOLVED: To protect a water against refrigerant heat exchanger from being frozen or overloaded without the application of a pump interlock control system in an air conditioning device based on a hydrothermal source system. SOLUTION: In an air conditioning device 1 provided with a hydrothermal source heat pump device and a fan 9 where a refrigerant pipeline 8 is constructed between a water against refrigerant heat exchanger 3, an expansion valve 4, a refrigerant against air heat exchanger 5, a four way valve 6 and a compressor 7, a first temperature detection device 11 which detects the water temperature near the inlet of heat source water of the water against refrigerant heat exchanger 3 and a second temperature detection device 12, which detects the water temperature near the outlet of heat source water, are provided. In the case where a differential temperature of each water temperature obtained from the detection result of the first and second temperature detection devices 11 and 12 is different from a predetermine value, a control device 13 halts the operation of the compressor 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling a water heat source air conditioner and a water heat source air conditioner having a protection function.

[0002]

2. Description of the Related Art For example, Japanese Patent Application Laid-Open No. 5-118595 discloses a "water heat source air conditioner unit and an air conditioner using the same." According to the disclosed technology, it is possible to provide an energy-saving air-conditioning system in which power consumption is leveled using an air-conditioning unit of a water heat source excellent in individual controllability, and furthermore, the machine room area is reduced and the It was possible to increase the effective area.

Referring to a simplified diagram, FIG.
As shown in (1), the heat source water from the cooling tower 101 is supplied to the air conditioners 103 and 104 of the water heat source installed in the target room by the pump 102, and is returned to the cooling tower 101 again. ing. In some cases, the auxiliary heat source 105 is connected to the heat source water circulation system via the three-way valve 106, and the heat source water from the auxiliary heat source 105 may be used by switching the three-way valve 106.

The air conditioner 10 installed in each room
Basically, the same type is used for 3 and 104. For example, when the configuration of the air conditioner 103 is described based on FIG. 4, a water-to-refrigerant heat exchanger 106, an expansion valve 107,
Refrigerant-to-air heat exchanger 108, four-way valve 109 and compressor 1
10 and a refrigerant pipe are formed to form a heat pump,
Further, a blower 111 for blowing the air supply SA into the room is provided.

In the water heat source type air conditioner 103 having such a configuration, the pump 1 for supplying heat source water is used.
Generally, the air conditioner 103 is controlled by a pump interlock so that the switch itself of the air conditioner 103 cannot be turned on unless the 02 operates. That is, the pump 102 and each of the air conditioners 103, 1
An operation signal line 114 of the pump 102 is wired between the control signal 113 and the control device 04. When the pump 102 is in a stopped state, the control device 113 operates and the air conditioner 103 cannot be operated.

[0006]

However, the above-mentioned protection by the conventional pump interlock has the following problems. First, in order to perform such pump interlock control, the operation signal line 14 of the pump 102 installed at a distant place is connected to the air conditioner 103, 1.
It is necessary to wire to the control device 113 in 04,
It takes time for construction work. When a large number of target rooms such as buildings exist and a large number of air conditioners 103 and the like are installed in accordance therewith, an extremely large amount of labor and cost are required, and the construction period becomes long. Even when the operation signal of the pump 102 is input, if the flow rate of the heat source water is out of an appropriate value due to, for example, water leakage, appropriate control cannot be performed only by the pump interlock. Need to be detected. This is because freezing or overload of the water-refrigerant heat exchanger cannot be detected. Therefore, from such a point, some kind of protection mechanism replacing the above-described pump interlock control is desired.

In this regard, for example, in order to prevent freezing of the water-to-refrigerant heat exchanger, an appropriate temperature detecting device is used, and when the water temperature reaches a preset temperature, the air conditioner is stopped. In order to prevent overload, it is conceivable to install a high-pressure switch or the like near the compressor outlet and to stop the air conditioner in the event of abnormally high pressure. If the temperature does not reach the set temperature, the protection mechanism does not work, so it takes time until it reaches the set temperature, and the burden on the piping that has already reached the set temperature is large, so new problems such as corrosion will occur Absent.

The present invention has been made in view of such a point, and it is possible to prevent freezing and overload of a water-to-refrigerant heat exchanger and to protect an air conditioner without using pump interlock control. It is a first object of the present invention to provide a control method of a water heat source air conditioner that can achieve the above. A second object of the present invention is to provide a water heat source air conditioner that can realize such protection.

[0009]

According to a first aspect of the present invention, a water-to-refrigerant heat exchanger, an expansion valve, a refrigerant-to-air heat exchanger, a four-way valve, and a compressor are provided. In a water heat source type air conditioning apparatus including a water heat source heat pump device formed by forming a heat pump by a refrigerant pipe, and a water heat source type air conditioner, a water temperature near a heat source water inlet in the water-to-refrigerant heat exchanger, and a heat source water outlet A method for controlling a water heat source air conditioner, comprising controlling the compressor based on a temperature difference from a water temperature in the vicinity.

According to the knowledge of the inventors, it is estimated whether the flow rate of the heat source water is appropriate based on the temperature difference between the water temperature near the heat source water inlet and the water temperature near the heat source water outlet in the water-to-refrigerant heat exchanger. be able to. Therefore, by estimating the heat source water flow rate based on this temperature difference, it becomes possible to know the details of the abnormality of the air conditioner. Therefore, the temperature difference is set beforehand by examining the temperature difference in the case of an appropriate flow rate, and if the temperature exceeds the range of the set appropriate temperature difference or if there is no temperature difference itself, the appropriate temperature difference is set. By judging that the flow rate is not flowing and stopping the operation of the compressor, the air conditioner can be protected.

According to a second aspect of the present invention, there is provided a heat pump, wherein a water-to-refrigerant heat exchanger, an expansion valve, a refrigerant-to-air heat exchanger, a four-way valve and a compressor are connected to a refrigerant pipe. A water heat source heat pump device comprising: a water heat source type air conditioner including a blower, a first temperature detection device for detecting a water temperature near a heat source water inlet of the water-to-refrigerant heat exchanger, A second temperature detecting device for detecting a water temperature near the heat source water outlet of the water-refrigerant heat exchanger, and a temperature difference between the respective water temperatures obtained from the detection results of the first and second temperature detecting devices are predetermined. And a protection mechanism for stopping the compressor when the set value is other than the set value, the water heat source air conditioner having a protection function is provided.

Here, the value other than the predetermined set value refers to the range of the temperature difference when the flow rate is determined to be appropriate in advance. However, as long as the heat source water is used as the heat source, the absence of the temperature difference means that the air conditioner is not operating normally. It is treated as outside the range of the temperature difference at the time of setting. Therefore, as described above, in cases other than such a predetermined temperature difference, it is considered that an appropriate flow rate is not flowing, and by stopping the operation of the compressor, the air conditioner can be protected. In this regard, in the case of claim 2, the stop is automatically performed by the protection mechanism. The protection mechanism having such a function can be embodied in an appropriate control device in an air conditioner, for example.

As described above, according to the first and second aspects of the present invention, the conventional pump interlock mechanism is not used,
The water heat source air conditioner can be protected. In the first and second aspects of the present invention, the compressor is appropriately controlled or stopped, but other devices other than the compressor, such as a blower, may be controlled and stopped simultaneously.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows an outline of the configuration of a water heat source type air conditioner 1 according to the present embodiment. The air conditioner 1 is installed and used, for example, on the ceiling of an air conditioning room.

The air conditioner 1 has a water-to-refrigerant heat exchanger 3 for exchanging heat between a heat source water supplied through an outgoing pipe 2 and a refrigerant. A refrigerant pipe 8 is provided between the heat exchanger 3 and the expansion valve 4, the refrigerant-to-air heat exchanger 5, the four-way valve 6, and the compressor 7 provided in the apparatus, as shown in the figure, to form a heat pump. doing. Further, a blower 9 is provided upstream of the air of the refrigerant-to-air heat exchanger 5.
Is provided, and the air after heat exchange in the refrigerant-to-air heat exchanger 5 is supplied to the room as air supply SA. With the above configuration, both the heating operation and the cooling operation can be performed by appropriately switching the four-way valve 6.

The heat source water from the forward pipe 2 is subjected to heat exchange in the water-to-refrigerant heat exchanger 3 and then returned from the return pipe 10 to, for example, a cooling tower (not shown). Near the inlet of the water, there is provided a first temperature detecting device 11 for detecting the temperature of the heat source water immediately before entering the water-to-refrigerant heat exchanger 3 from the outgoing pipe 2, while near the outlet of the heat source water, A second temperature detection device 12 that detects the temperature of the heat source water immediately after the heat exchange in the refrigerant heat exchanger 3 is provided.

The detection results from the first temperature detecting device 11 and the second temperature detecting device 12 are input to a control device 13 provided in the device. The control device 13 determines the water temperature near the inlet of the heat source water from these detection results,
The temperature difference between the water temperature near the outlet and the temperature difference is compared with a preset appropriate temperature difference (range), and an ON-OFF signal is output to the compressor 7 based on the magnitude of the difference. Have been.

The main part of the air conditioner 1 according to the present embodiment has the above-described configuration. An example of the control flow will be described with reference to the flowchart of FIG. When turned ON (step S
1) The compressor 7 operates (step S2), and the operation of the air conditioner 1 is started. The power supply of the air conditioner 1 is
When set to N, a pump for supplying heat source water (not shown)
Is in operation. Therefore, the air conditioner 1 and a power source such as a pump are separate power sources.

Next, the first temperature detecting device 11 and the second temperature detecting device 12 immediately detect the temperature near the inlet / outlet of the water-to-refrigerant heat exchanger 3 and constantly output the result to the control device 13 ( Step S3).

In the control device 13, based on the detection results of the first temperature detection device 11 and the second temperature detection device 12,
A temperature difference between the water temperature near the inlet of the heat source water and the water temperature near the outlet is determined, and the temperature difference is compared with a preset appropriate temperature difference (range) (step S4). In the present control flow example, as shown in FIG. 2, during the heating operation, for example, the appropriate temperature difference (range) is set to 1 deg to 6 deg, and the temperature difference t obtained from the detection result is 1 deg to 6 deg. That is, when 1 deg ≦ t ≦ 6 deg, it is determined that an appropriate temperature difference, that is, an appropriate flow rate is flowing, and the process returns to step S3. If the temperature is smaller (t <1 deg) or larger (t> 6 deg) or the temperature difference is 0 (t = 0), a stop signal is output to the compressor 7,
The compressor 7 is stopped, and thereafter, the air conditioner 1 starts the blow operation by the blower 9. In this case, an appropriate warning signal may be output at the same time to notify the outside. Further, not only the compressor 7 but also the air conditioner 1 itself may be stopped.

On the other hand, during the cooling operation, when the detected temperature difference t is 2 deg to 13 deg, that is, 2 deg ≦ t
If ≤13 deg, an appropriate temperature difference, that is, an appropriate flow rate is determined to be flowing, and the process returns to step S3. However, the temperature difference obtained by the detection result is smaller than 2 deg to 13 deg (t
If <2 deg) or large (t> 13 deg) or if the temperature difference is 0 (t = 0), a stop signal is output to the compressor 7. As a result, the compressor 7 is stopped, and thereafter, the air blow operation by the blower 9 is started. At this time, an appropriate warning signal may be output at the same time to notify the outside. Further, not only the compressor 7 but also the air conditioner 1 itself may be stopped.

According to the findings of the inventors, the following Table 1 shows the difference between the temperature difference t obtained from the detection result and the appropriate temperature difference.
The situation shown in FIG.

[0023]

[Table 1]

That is, during the heating operation, the temperature difference t is zero.
In this case, it is presumed that the heat source water is not flowing to the water-to-refrigerant heat exchanger 3, and the water-to-refrigerant heat exchanger 3 freezes if this state is maintained. When the temperature difference t is larger than the set temperature difference, the flow rate of the heat source water is estimated to be smaller than the minimum value of the usage range of the water-to-refrigerant heat exchanger 3, and the water-to-refrigerant heat exchanger 3 is similarly frozen. Resulting in. Conversely, when the temperature difference t is smaller than the set temperature difference, it is estimated that the flow rate of the heat source water is larger than the maximum value of the usage range of the water-to-refrigerant heat exchanger 3, and it is finally determined that the overload state is present. .

On the other hand, during the cooling operation, the temperature difference t is zero.
In this case, it is presumed that the heat source water is not flowing to the water-to-refrigerant heat exchanger 3, and in this case, it is determined that there is an overload. If the temperature difference t is larger than the set temperature difference, it is estimated that the flow rate of the heat source water is smaller than the minimum value of the usage range of the water-to-refrigerant heat exchanger 3, and it is also determined that the heat load is overloaded. You. Conversely, when the temperature difference t is smaller than the set temperature difference, it is estimated that the flow rate of the heat source water is larger than the maximum value of the usage range of the water-to-refrigerant heat exchanger 3, and the refrigerant-to-air heat exchanger 5 freezes. Would be.

Therefore, as in the air conditioner 1 according to the present embodiment, the detected temperature difference t is compared with the set temperature difference.
Is stopped, freezing of the water-to-refrigerant heat exchanger 3 and freezing of the refrigerant-to-air heat exchanger 5 can be prevented beforehand, and even in the case of overload, the water-to-refrigerant heat exchanger 3 and the refrigerant piping can be prevented. 8
Can be prevented from becoming large, and post-processing can be performed quickly. Therefore, each device of the air conditioner 1 can be appropriately protected. In addition, since the compressor 7 is stopped and the air blowing operation by the blower 9 is performed, the wind circulates, so that dew condensation does not occur in the pipe between the expansion valve 4 and the water-to-refrigerant heat exchanger 3. .
Of course, when a drain pan or the like is installed below the air conditioner 1, the blower 9 may be stopped simultaneously with the compressor 7.

Moreover, the configuration for exhibiting such a protection function is provided with a first temperature detecting device 11 and a second temperature detecting device 12 at the entrance and exit of the heat source water of the air conditioner 1, and the detection results are obtained. Output to the control device 13
Since the ON / OFF of the compressor is controlled by the air conditioner, only the wiring around the air conditioner 1 is required for wiring. Therefore, wiring work is also very simple. Even if a large number of air conditioners are installed, only the individual air conditioners are required, and there is no need to wire a remote device (for example, a pump) as in the related art.

The appropriate temperature difference (range) set in the air conditioner 1 according to the above-described embodiment is appropriately set according to the rating of the water-to-refrigerant heat exchanger 3 and the like. However, the present invention is not limited to this.

[0029]

According to the first and second aspects of the present invention, it is possible to protect the air conditioner by preventing freezing and overload of the water-refrigerant heat exchanger without using the pump interlock control. it can. Further, since the compressor is immediately stopped based on the temperature difference, an excessive load is not applied to the water-to-refrigerant heat exchanger and the refrigerant piping, so that there is no problem such as corrosion. In addition, wiring work with equipment located away from the air conditioner, which was necessary when adopting conventional pump interlock control, can be eliminated.For example, only wiring within the equipment is required, so extremely simple work is possible. Good.

[Brief description of the drawings]

FIG. 1 is an explanatory view schematically showing a configuration of an air conditioner according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram illustrating an example of a control flow of the air-conditioning apparatus of FIG. 1;

FIG. 3 is an explanatory diagram showing a relationship between a conventional air conditioner employing a pump interlock control and a pump.

FIG. 4 is an explanatory view schematically showing a configuration of a conventional air conditioner employing pump interlock control.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Air conditioner 2 Outgoing pipe 3 Water-to-refrigerant heat exchanger 4 Expansion valve 5 Refrigerant-to-air heat exchanger 6 Four-way valve 7 Compressor 8 Refrigerant piping 9 Blower 10 Return pipe 11 First temperature detecting device 12 Second temperature Detection device 13 Control device

Claims (2)

[Claims] 1. A water heat source heat pump device comprising a heat pump formed by connecting a water pipe to a refrigerant heat exchanger, an expansion valve, a refrigerant to air heat exchanger, a four-way valve, and a compressor to form a heat pump, and a blower. In a water heat source type air conditioner, the compressor is controlled based on a temperature difference between a water temperature near a heat source water inlet and a water temperature near a heat source water outlet in the water-to-refrigerant heat exchanger. To control a water heat source air conditioner. 2. A water heat source heat pump device in which a heat pump is formed by connecting a water pipe to a refrigerant heat exchanger, an expansion valve, a refrigerant to air heat exchanger, a four-way valve, and a compressor, and a blower. In a water heat source type air conditioner, a first temperature detecting device that detects a water temperature near a heat source water inlet of the water-to-refrigerant heat exchanger, and a water temperature near a heat source water outlet of the water-to-refrigerant heat exchanger are detected. A second temperature detecting device, and a protection mechanism for stopping the compressor when a temperature difference between respective water temperatures obtained from the detection results of the first and second temperature detecting devices is other than a predetermined set value. A water heat source air conditioner having a protection function, comprising: