JP2963014B2 - Air conditioner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner in which a heat exchanger for a refrigerant in which a refrigerant flows and a heat exchanger for a hot water in which hot water flows are arranged in the same body.

[0002]

2. Description of the Related Art An air conditioner of this type is disclosed, for example, in Japanese Patent Application Laid-Open No. Hei 4-165247. This publication describes an air conditioner and an air conditioner in which a heat exchanger for refrigerant in which a refrigerant flows inside and a heat exchanger for hot water in which hot water flows inside are arranged in the same body. In such an air conditioner, generally, after the installation work of the air conditioner is completed, it is confirmed that there is no mistake in the installation work by using a trial run to confirm whether the air conditioner operates normally. ing.

[0003]

In the above-described air conditioner, especially when the cooling test operation must be performed in winter or when the outdoor temperature is low, the heat exchanger for refrigerant and the heat exchanger for hot water come into contact with each other. In general, the heat exchanger for hot water is rapidly and locally cooled by the heat exchanger for refrigerant in which the refrigerant flows, because the heat exchangers are commonly used and both heat exchangers also serve as heat transfer fins. The hot water heat exchanger may freeze and burst. In addition, in order to avoid the possibility of the rupture, the cooling test run may not be performed. In this case, even if there is a mistake in the installation work, the mistake cannot be found.

[0004] The present invention provides an air conditioner capable of performing a cooling test run even when the outdoor temperature is low.

[0005]

In order to solve the above-mentioned problems, a heat exchanger for a refrigerant in which a refrigerant flows inside and a heat exchanger for a hot water in which hot water flows inside are arranged in the same machine body, In an air conditioner including a control device that controls an operating frequency of a compressor connected to a heat exchanger and operates the compressor during a cooling test run, the first invention includes a detector that detects an outdoor air temperature. The control device is provided with control means for reducing the operating frequency during the cooling test operation when the outdoor air temperature detected by the detector is equal to or lower than a predetermined temperature, and a second invention provides the air conditioner, The air conditioner is provided with a detector for detecting the outdoor air temperature, and the control device is provided with control means for raising and lowering the operating frequency during the cooling test run according to the level of the outdoor air temperature detected by the detector.

A plurality of indoor units having a heat exchanger for refrigerant in which a refrigerant flows therein and a heat exchanger for hot water in which hot water flows therein are arranged in a single body, and a compression unit connected to the refrigerant heat exchanger. In an air conditioner including a control device for controlling an operation frequency of the compressor and operating the compressor during a cooling test run, a third invention includes a detector for detecting an outdoor air temperature, and the control device includes: When the outdoor air temperature detected by the detector is equal to or lower than a predetermined temperature, control means is provided for lowering the operation frequency during the cooling test operation. The fourth invention provides the air conditioner, wherein the outdoor air temperature detects the outdoor air temperature. The air conditioner includes a detector, and the control device is provided with control means for raising and lowering the operating frequency during the cooling test run according to the level of the outdoor temperature detected by the detector.

[0007]

In the air conditioners of the first to fourth aspects of the present invention, when the outdoor temperature is low, the operating frequency of the compressor is reduced by the control means, so that the hot water heat exchanger is cooled by the refrigerant heat exchanger. Speed can be reduced.

In the air conditioners according to the second and fourth aspects of the present invention, the operating frequency of the compressor is increased or decreased by the control means in accordance with the level of the outdoor temperature. Is greatly reduced, so that the refrigerant circulation amount is prevented from being significantly reduced.

[0009]

An embodiment of the present invention will be described with reference to the drawings. 1
Is an outdoor unit of an air conditioner, and a service valve 2A, 2B, 2C, a muffler 3, an accumulator 4, 5, a
Compressor 6, muffler 7, outdoor heat exchanger 8, modulator 9, strainer 1 whose capacity can be changed according to the operating frequency
0, the electric expansion valve 11 for adjusting the circulation amount of the refrigerant flowing to the outdoor unit, the electric expansion valves 12A, 12B, 12C for adjusting the circulation amount of the refrigerant flowing to each indoor unit, and the indoor unit and the refrigerant pipe. Service valves 13A, 13 for connecting
B and 13C are connected by piping between units, and these are stored. 14 is a detector for detecting the temperature of the air on the primary side of the outdoor heat exchanger, that is, the outdoor air temperature;
Is a control device that controls the operating frequency of the compressor and controls the operating frequency of the compressor 6 as shown in FIG. 2 according to the signal from the detector 14 during the cooling test operation, and is configured by a microcomputer or the like. Although not shown, control means is provided.

An indoor unit 16A is connected to an outdoor unit 1 having a compressor 6 and an outdoor heat exchanger 8 and a heat source unit (not shown) having a hot water supply device such as a boiler to constitute an air conditioner. A heat exchanger 17A for a refrigerant through which a refrigerant flows and a heat exchanger 18A for a hot water through which hot water flows are housed in the same machine body, and these heat exchangers also serve as heat transfer fins, They are joined together or placed in very close proximity. Further, in these heat exchangers, the refrigerant heat exchanger 17A is disposed on the primary side (windward side) of the hot water heat exchanger 18A. 19A is a test operation switch for performing a test operation, and 20A is a detector for detecting the refrigerant temperature, which is arranged on the upstream side of the refrigerant heat exchanger 17A. 21A is a detector for detecting the temperature of the hot water in the intermediate portion of the heat exchanger for hot water 17A.
It is arranged in the middle part of. 22A is a detector 20A,
An indoor-side controller for controlling an indoor fan (not shown) and an outdoor unit in accordance with a signal from the 21A and a signal from the test operation switch 19A, and is connected to the outdoor-side controller 15 by a signal line (not shown). I have. Reference numeral 16B denotes an indoor unit, similar to the indoor unit 16A. The indoor unit 16B includes a heat exchanger for refrigerant 17B, a heat exchanger for hot water 18B, a detector 18B, a test run switch 19B, detectors 20B and 21B, and a control device 2
Similarly, the indoor unit 16C includes a refrigerant heat exchanger 17C, a hot water heat exchanger 18C, a detector 18C, a trial operation switch 19C, detectors 20C and 21C, and a controller 22C. Further, the indoor units 16A, 16B, 1
6C is an auxiliary pipe 25A, 25B, 25C, 26A, 2
6B and 26C, and a connecting portion 27
A, 27B, 27C, 28A, 28B, 28C. And the connection parts 27A, 27B, 27C, 28
A, 28B, 28C and valves 2A, 2B, 2C, 13
A, 13B, and 13C are connected to the interunit piping 29, respectively.
A, 29B, 29C, 30A, 30B, 30C.

The indoor units 16A, 16B and 16C are provided with hot water pipes 31A, 31B, 31C, 32A, 32B and 32, respectively.
C is connected to a heat source unit that supplies hot water.

In the air conditioner configured as described above, the indoor units 16A, 16B, 16C, the outdoor unit, and the heat source unit are connected to unit piping 29A, 29B, 29C, 30A, 30B, 3B.
0C or hot water piping 31A, 31B, 31C, 32A, 32
When the installation work is completed by connecting the B and 32C via signal lines (not shown), a test operation is performed to check whether the air conditioner operates normally or the installation work is correctly performed. The test operation is a heating test operation in which hot water is supplied to the hot water heat exchanger for heating, and a refrigerant is supplied to the refrigerant heat exchanger to dehumidify and cool the air, and the dehumidified and cooled air is reheated in the hot water heat exchanger. Dehumidification trial run (only the cooling trial run and heating trial run are performed, and this dehumidification trial run may be omitted)
Then, a cooling test operation in which the refrigerant flows through the refrigerant heat exchanger to perform cooling is performed.

First, when performing a cooling test run, first, a wireless remote control (not shown) is used to set a cooling operation mode and turn on a test run switch. Then, a cooling test run of the indoor unit is started. Similarly, when performing the dehumidification test run, first set the mode of the dehumidification operation with the wireless remote control, and turn on the test operation switch, the dehumidification test operation is started, and when performing the heating test operation,
First, when the mode of the heating operation is set by the wireless remote controller and the test operation switch is turned on, the heating test operation is started.

The heating test operation and the dehumidifying test operation can be performed even in a severe cold season or when the outdoor temperature is low because there is no danger of freezing and rupture of the hot water heat exchanger because hot water flows through the hot water heat exchanger. In the case of test operation, when the temperature of the cold water or the outdoor temperature is low, the heat exchanger for the coolant quickly and locally cools the heat exchanger for the hot water adjacent to the heat exchanger for the coolant. Danger of freezing and rupture.

However, in the air conditioner of the present invention, the operating frequency of the compressor is controlled as shown in FIG. 2 according to the outdoor temperature, so that the hot water heat exchanger is not rapidly cooled. Because of the control, freezing and rupture of the hot water heat exchanger can be prevented.

That is, when the outdoor air temperature during the cooling test operation is 21
If the temperature is higher than 0 ° C., the outdoor temperature is sufficiently high and there is no danger of freezing and rupture of the hot water heat exchanger, and the compressor is operated at the rated frequency of 75 Hz as in the conventional air conditioner. When the outdoor air temperature is lower than 21 ° C., the outdoor air temperature is low, and the evaporation temperature of the refrigerant is low, so that there is a danger of freezing and rupture of the hot water heat exchanger. As shown in FIG. Further, when the outdoor air temperature is low and lower than 5 ° C. and higher than 0 ° C., the compressor is operated at 25 Hz. This operation frequency of 25 Hz is set to a higher frequency than the minimum operation frequency. If the outdoor air temperature is lower than 0 ° C., even if the operating frequency of the compressor is lowered to the minimum operating frequency, there is a possibility that the freezing and rupture of the hot water heat exchanger may not be prevented. Control is not performed).

In this air conditioner, the indoor unit and the outdoor unit are controlled by detecting the outdoor air temperature and the indoor air temperature. The detection of the outdoor air temperature at the time of the cooling test operation is the same as the detection of the outdoor air temperature during the normal cooling operation. The same (for example, detection every several milliseconds) is set. It is not desirable that the operating frequency of the compressor greatly fluctuates during the cooling test run. The operating frequency is continuously changed within the range of 5 ° C. or more and less than 21 ° C. as shown in FIG. The operating frequency does not fluctuate significantly.

At the time of the cooling test operation, when the outdoor air temperature is low, when the refrigerant flows into the refrigerant heat exchanger, the hot water heat exchanger is rapidly and locally cooled, and there is a risk of freezing and rupture. However, in the air conditioner of the present invention, when the outdoor air temperature is low (less than 21 ° C.), the operating frequency of the compressor is reduced, so that the cooling speed of the hot water heat exchanger can be reduced. In addition, freezing and rupture of the heat exchanger for hot water can be prevented. Further, in the air conditioner having a plurality of indoor units such as this air conditioner, a state in which so-called erroneous piping such as a failure to connect a signal line or a connection error, or a connection and an error in piping may also occur. Conceivable. If the indoor fan (not shown) does not rotate during the cooling test run in the state of the incorrect piping, the heat exchanger for hot water may be rapidly and locally cooled, frozen and ruptured. However, in this air conditioner, when the outdoor temperature at which the heat exchanger for hot water freezes and ruptures is low, the operating frequency of the compressor is controlled so as to be reduced.
The cooling speed of the hot water heat exchanger is reduced, and freezing and rupture of the hot water heat exchanger can be prevented as much as possible.

Further, when the outdoor temperature is in the range of 5 ° C. to 21 ° C., the operating frequency of the compressor is increased or decreased according to the level of the outdoor temperature, so that the operating frequency becomes too low when the outdoor temperature is relatively high. As a result, it is possible to prevent the amount of the circulated refrigerant from being excessively reduced, thereby preventing the temperature of the heat exchanger for the refrigerant from decreasing significantly, thereby prolonging the cooling test run time.

When the cooling units of the indoor units 16A, 16B, and 16C are sequentially subjected to the cooling test operation, and it is confirmed that there is no mistake in the installation work of these cooling circuits, the heating test operation and the dehumidification test operation are performed. Then, after confirming that there is no installation work mistake in the heating circuit and both the cooling and heating circuits, the test operation is completed.

In this embodiment, an air conditioner is composed of an outdoor unit having a compressor and an outdoor heat exchanger, a heat source unit having a boiler, and an indoor unit connected to these units. The present invention is not limited to this example, and an air conditioner may be configured by an outdoor unit having a compressor, an outdoor heat exchanger, a heat source unit, and the like in the same body, and an indoor unit connected to the outdoor unit.

Furthermore, when the outdoor air temperature is detected only at the beginning of the cooling test operation and the compressor is operated at the operation frequency corresponding to this temperature until the end of the cooling test operation, the difference between the outdoor air temperature and the operation frequency is determined. Even if the relationship is stepped as shown in FIG. 2A, a significant change in the operating frequency can be prevented.

[0023]

According to the air conditioners of the first to fourth aspects,
When the outdoor air temperature is low, the operating frequency of the compressor is reduced by the control means, the speed at which the heat exchanger for hot water is cooled by the heat exchanger for refrigerant can be reduced, and freezing of the heat exchanger for hot water, Since the rupture can be prevented, the cooling test run can be performed even when the outdoor temperature is low. In particular, in the air conditioners of the third and fourth aspects of the invention, even if there is an erroneous piping in the installation work, freezing and rupture of the hot water heat exchanger can be prevented.

In the air conditioners according to the second and fourth aspects of the present invention, the operating frequency of the compressor is increased or decreased in accordance with the outdoor temperature. Therefore, when the outdoor temperature is relatively high, the operating frequency becomes too low. Thus, it is possible to prevent a problem that the circulation amount of the refrigerant is reduced and the time for the cooling test run must be lengthened.

[Brief description of the drawings]

FIG. 1 is a circuit diagram of a refrigerant and hot water of an air conditioner of the present invention.

FIG. 2 is a diagram showing a relationship between an outdoor temperature and an operation frequency.

[Explanation of symbols]

 6 Compressor 14 Detector 15, 22A, 22B, 22C Controller 16A, 16B, 16C Indoor unit 17A, 17B, 17C Refrigerant heat exchanger 18A, 18B, 19C Hot water heat exchanger

Claims (4)

(57) [Claims] 1. A heat exchanger for a refrigerant in which a refrigerant flows therein and a heat exchanger for a hot water in which hot water flows therein are disposed in the same machine body, and the operating frequency of a compressor connected to the refrigerant heat exchanger is adjusted. An air conditioner provided with a control device for controlling and operating the compressor at the time of a cooling test run, a detector for detecting an outdoor air temperature is provided, and the outdoor air temperature detected by the detector is a predetermined temperature. An air conditioner comprising a control means for lowering the operating frequency during the cooling test operation in the following cases. 2. A heat exchanger for a refrigerant in which a refrigerant flows therein and a heat exchanger for a hot water in which hot water flows therein are arranged in the same machine body, and an operating frequency of a compressor connected to the refrigerant heat exchanger is adjusted. An air conditioner having a control device for controlling and operating the compressor at the time of a cooling test operation, including a detector for detecting an outdoor air temperature, wherein the control device includes a detector for detecting whether the outdoor air temperature detected by the detector is high or low. An air conditioner further comprising control means for raising and lowering the operating frequency during the cooling test run. 3. A plurality of indoor units each including a refrigerant heat exchanger in which a refrigerant flows therein and a hot water heat exchanger in which hot water flows therein are arranged in the same body, and a compression unit connected to the refrigerant heat exchanger. An air conditioner equipped with a control device for controlling the operating frequency of the air conditioner and operating the compressor during a cooling test run includes a detector for detecting an outdoor air temperature, and the control device detects the outdoor air temperature. An air conditioner comprising a control means for lowering the operating frequency during the cooling test run when the outdoor air temperature is equal to or lower than a predetermined temperature. 4. A plurality of indoor units each including a refrigerant heat exchanger in which a refrigerant flows inside and a hot water heat exchanger in which hot water flows inside are disposed in the same body, and a compression unit connected to the refrigerant heat exchanger. An air conditioner having a control device for controlling the operating frequency of the air conditioner and operating the compressor at the time of a cooling test operation, including an outdoor air temperature detector for detecting an outdoor air temperature, wherein the control device includes: An air conditioner comprising a control means for raising and lowering the operating frequency during the cooling test operation according to the detected outdoor temperature.