JPH08110105A - Air conditioner - Google Patents

Abstract

PURPOSE: To prevent the freezing, the bursting of a heat exchanger for warm water by providing a sensor for detecting the outdoor air temperature when the outdoor air temperature is a predetermined temperature or lower at the time of trially cooling of an installation construction and lowering the operating frequency of a compressor. CONSTITUTION: At the time of trially cooling an air conditioner in which an outdoor unit 1, indoor units 16A, 16B, 16C are coupled by tubes between the contained units, a controller 16 is operated in response to a signal from an outdoor air temperature sensor 14 to control the operating frequency of a compressor 6, thereby preventing the freezing, the bursting of a heat exchanger for warm water. When the outdoor air temperature is 21 deg.C or higher, there is no danger of freezing, bursting the exchanger for the warm water, and the compressor is operated at a rated frequency of 75Hz. When the outdoor air temperature is 21-5 deg.C, the outdoor air temperature is low and the evaporating temperature of the refrigerant becomes low, and hence it is considered to be dangerous, and the operating frequency of the compressor is linearly lowered to 69-26Hz. When it is 5-0 deg.C, it is operated at the frequency of 25Hz. Further, when it is lower than 0 deg.C, it is dangerous, and hence it is so controlled as to refrain the trial operation.

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 refrigerant heat exchanger in which a refrigerant flows and a hot water heat exchanger 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 described, for example, in Japanese Patent Application Laid-Open No. 4-165247. This publication describes an air conditioner air conditioner in which a refrigerant heat exchanger through which a refrigerant flows and a hot water heat exchanger through which hot water flows therein are arranged in the same body. In such an air conditioner, generally after the completion of the installation work of the air conditioner, use a trial run to confirm whether the air conditioner works normally, and confirm that there are no mistakes in the installation work. ing.

[0003]

In the air conditioner described above, the heat exchanger for refrigerant and the heat exchanger for hot water are in contact with each other, especially when the cooling test operation must be performed in winter or when the outdoor temperature is low. The heat exchanger for hot water is cooled rapidly and locally by the heat exchanger for refrigerant through which the refrigerant flows, because the heat exchanger for heat exchanger is generally arranged such that both heat exchangers also serve as heat transfer fins. , The hot water heat exchanger could freeze and burst. In addition, in order to avoid the possibility of bursting, the cooling test operation may not be carried out. In this case, even if there was a mistake in the installation work, this mistake could not be found.

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

[0005]

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

Further, a plurality of indoor units 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 flow inside are arranged in the same body are provided, and the compressor is connected to the heat exchanger for a refrigerant. In an air conditioner including a control device for controlling an operating frequency of a machine and for operating the compressor during a cooling test operation, a third invention includes a detector for detecting an outdoor air temperature, and the control device includes: A control means for lowering the operating frequency during the cooling test operation is provided when the outdoor air temperature detected by the detector is equal to or lower than a predetermined temperature, and the fourth aspect of the invention is the outdoor air temperature detecting the outdoor air temperature in the air conditioner. A detector is provided, and the control device is provided with control means for increasing or decreasing the operation frequency during the cooling test operation in accordance with the outdoor temperature detected by the detector.

[0007]

In the air conditioners of the first to fourth aspects of the invention, when the outdoor air temperature is low, the operating frequency of the compressor is lowered by the control means, so that the heat exchanger for refrigerant cools the hot water heat exchanger. Can be slowed down.

In the air conditioners of the second and fourth aspects of the invention, the operating frequency of the compressor is raised or lowered by the control means according to the level of the outdoor air temperature, so that the operating frequency of the compressor is high when the outdoor air temperature is high. It is possible to prevent the refrigerant circulation amount from being greatly reduced by greatly reducing

[0009]

Embodiments of the present invention will be described with reference to the drawings. 1
Is an outdoor unit of an air conditioner, and in the body of this outdoor unit, service valves 2A, 2B, 2C, muffler 3, accumulators 4, 5 for connecting each indoor unit with piping between units are provided.
Compressor 6, muffler 7, outdoor heat exchanger 8, modulator 9, strainer 1 whose capacity can be changed by operating frequency
0, electric expansion valve 11 for adjusting the circulation amount of the refrigerant flowing to the outdoor unit, electric expansion valves 12A, 12B, 12C for adjusting the circulation amount of the refrigerant flowing to each indoor unit, and each indoor unit and 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 temperature, 15
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 in response to a signal from the detector 14 during a cooling test operation, and is composed of a microcomputer or the like. Although not shown, a 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. In the machine, a refrigerant heat exchanger 17A in which a refrigerant flows and a hot water heat exchanger 18A in which hot water flows are housed in the same machine body. These heat exchangers also function as heat transfer fins or a tube sheet. Combined with each other or placed in close proximity. Further, in these heat exchangers, the refrigerant heat exchanger 17A is arranged on the primary side (windward side) of the hot water heat exchanger 18A. Reference numeral 19A is a test operation switch for performing a test operation, and 20A is a detector for detecting the temperature of the refrigerant, which is arranged upstream of the heat exchanger for refrigerant 17A. Reference numeral 21A denotes a detector for detecting the temperature of hot water in the middle portion of the heat exchanger for hot water 17A.
It is located in the middle part of. 22A is a detector 20A,
An indoor-side control device for controlling an indoor fan (not shown) and an outdoor unit according to a signal from 21A and a signal from the trial run switch 19A, and is connected to the outdoor-side control device 15 by a signal line (not shown). There is. 16B is an indoor unit, and like the indoor unit 16A, this indoor unit 16B includes a heat exchanger for refrigerant 17B, a heat exchanger for hot water 18B, a detector 18B, a test operation switch 19B, detectors 20B and 21B, and a controller 2.
Similarly, the indoor unit 16C includes a refrigerant heat exchanger 17C, a hot water heat exchanger 18C, a detector 18C, a test operation switch 19C, detectors 20C and 21C, and a controller 22C. Further, the indoor units 16A, 16B, 1
6C is auxiliary piping 25A, 25B, 25C, 26A, 2
6B, 26C, and a connecting portion 27 at the tip of these
A, 27B, 27C, 28A, 28B, 28C. Then, the connecting portions 27A, 27B, 27C, 28
A, 28B, 28C and valves 2A, 2B, 2C, 13
A, 13B, and 13C are the inter-unit pipes 29, respectively.
They are connected by A, 29B, 29C, 30A, 30B and 30C.

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

In the air conditioner thus constructed, the indoor units 16A, 16B and 16C, the outdoor unit and the heat source unit are connected between the unit pipes 29A, 29B, 29C, 30A, 30B and 3B.
0C and hot water pipes 31A, 31B, 31C, 32A, 32
B, 32C, connected by a signal line (not shown), and when the installation work is completed, a test operation is performed to confirm whether the air conditioner operates normally or whether the installation work is performed correctly. The test run is a heating test run in which hot water is passed through the hot water heat exchanger to heat it, and a refrigerant is passed through 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 test run (this dehumidification test run may be omitted by performing only a cooling test run and a heating test run)
Then, a cooling trial operation is performed in which the refrigerant is caused to flow through the refrigerant heat exchanger to cool the refrigerant.

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

The heating test operation and dehumidification test operation can be performed because there is no risk of freezing or rupture of the hot water heat exchanger even in a severe cold season or when the outdoor temperature is low, because the hot water heat exchanger flows into the hot water heat exchanger. In the case of a test run, during a severe cold season or when the outdoor temperature is low, the heat exchanger for hot water that is close to the heat exchanger for refrigerant is cooled rapidly and locally by this heat exchanger for hot water. However, there is a risk of freezing and bursting.

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 heat exchanger for hot water is not cooled rapidly. Since it is controlled, the heat exchanger for hot water can be prevented from freezing and bursting.

That is, the outdoor air temperature during the cooling trial operation is 21
If the temperature is above ℃, it is considered that there is no risk of freezing and rupture of the heat exchanger for hot water because the outdoor air temperature is sufficiently high, and the compressor is operated at the rated frequency of 75 Hz as in the conventional air conditioner. Further, 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 risk of freezing and bursting of the heat exchanger for hot water. As shown in, decrease linearly and continuously. Furthermore, when the outdoor temperature is low, less than 5 ° C., and 0 ° C. or higher, the compressor is operated at 25 Hz. This operating frequency of 25 Hz is set to a frequency higher than the lowest operating frequency. If the outdoor air temperature is below 0 ° C, even if the operating frequency of the compressor is lowered to the minimum operating frequency, it may not be possible to prevent freezing and rupture of the heat exchanger for hot water. Control it so that it will not be operated).

In this air conditioner, the indoor unit and the outdoor unit are controlled by detecting the outdoor air temperature and the indoor air temperature, and the outdoor air temperature during the air conditioning trial run is also detected. The same (for example, detection every few milliseconds) is set. It is not desirable that the operating frequency of the compressor fluctuates greatly during the cooling test operation, and the operating frequency is continuously changed within the range of 5 ° C or higher and lower than 21 ° C as shown in Fig. 2. Therefore, in this air conditioner, The operating frequency does not fluctuate significantly.

When the outdoor air temperature is low during the cooling operation, if the refrigerant flows into the heat exchanger for refrigerant, the heat exchanger for hot water is rapidly and locally cooled, and there is a fear that the heat exchanger may freeze or burst. 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 lowered, so the cooling speed of the hot water heat exchanger can be slowed down. It is possible to prevent freezing and rupture of the heat exchanger for hot water. Also, in the case of having a plurality of indoor units such as this air conditioner, there is also a state of so-called incorrect piping, such as misconnecting or misconnecting the signal line, or connecting the pipes incorrectly. Conceivable. If the indoor fan (not shown) does not rotate during the cooling test operation with this incorrect piping, the hot water heat exchanger may be rapidly and locally cooled, frozen, and burst. However, in this air conditioner, when the outdoor temperature is low such that the heat exchanger for hot water freezes or bursts, the operating frequency of the compressor is controlled to be lowered,
The cooling speed of the hot water heat exchanger is slowed down, and the freezing and rupture of the hot water heat exchanger can be prevented as much as possible.

Further, in the range of the outdoor air temperature of 5 ° C. to 21 ° C., the operating frequency of the compressor is raised or lowered according to the level of the outdoor air temperature, so that the operating frequency becomes too low when the outdoor temperature is relatively high. Therefore, it is possible to prevent the circulation amount of the refrigerant from being reduced too much, which causes the temperature of the heat exchanger for the refrigerant to be significantly reduced at a low speed, which requires a long cooling test operation time.

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

In this embodiment, the air conditioner is composed of the outdoor unit equipped with the compressor and the outdoor heat exchanger, the heat source unit equipped with the boiler, and the indoor unit connected to them. The air conditioner is not limited to the example, and an air conditioner may be configured by an outdoor unit including 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.

Further, when the outdoor air temperature is detected only at the beginning of the cooling test operation and the compressor is operated at the operating frequency corresponding to this temperature until the end of the cooling test operation, the outdoor air temperature and the operating frequency are Even if the relationship is stepwise as shown in FIG. 2A, it is possible to prevent a large change in the operating frequency.

[0023]

According to the air conditioner of the first to fourth inventions,
When the outdoor air temperature is low, the operating frequency of the compressor is lowered by the control means, the rate at which the heat exchanger for hot water is cooled by the heat exchanger for refrigerant can be slowed, and the heat exchanger for hot water is frozen, Since the burst can be prevented, the cooling test operation 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 the installation work involves incorrect piping, it is possible to prevent the heat exchanger for hot water from freezing and bursting.

Further, particularly in the air conditioners of the second and fourth aspects of the invention, since the operating frequency of the compressor is raised or lowered according to the outdoor temperature, the operating frequency becomes too low when the outdoor temperature is relatively high. Therefore, it is possible to prevent the problem that the circulation amount of the refrigerant is reduced and the cooling test operation time is required to be lengthened.

[Brief description of 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 operating frequency.

[Explanation of symbols]

 6 Compressor 14 Detector 15, 22A, 22B, 22C Controller 16A, 16B, 16C Indoor unit 17A, 17B, 17C Heat exchanger for refrigerant 18A, 18B, 19C Heat exchanger for hot water

Claims (4)

[Claims] 1. A refrigerant heat exchanger in which a refrigerant flows inside and a hot water heat exchanger in which hot water flows inside are arranged in the same body, and an operating frequency of a compressor connected to the refrigerant heat exchanger is set. In an air conditioner having a control device that controls and operates the compressor during a cooling test operation, a detector that detects an outdoor air temperature is provided, and the outdoor air temperature detected by the detector is a predetermined temperature in the control device. An air conditioner comprising control means for decreasing the operating frequency during the cooling test operation in the following cases. 2. 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 body, and an operating frequency of a compressor connected to the heat exchanger for a refrigerant is set. An air conditioner that controls and operates a compressor during a cooling test run, in an air conditioner that includes a detector that detects an outdoor temperature, and in the control device, the outdoor air temperature detected by this detector is controlled to be high or low. Accordingly, the air conditioner is provided with control means for increasing or decreasing the operating frequency during the cooling test operation. 3. A compressor provided with a plurality of indoor units in which a heat exchanger for refrigerant through which a refrigerant flows and a heat exchanger for hot water through which hot water flows inside are arranged in the same body, and which is connected to the heat exchanger for refrigerant. An air conditioner that controls the operating frequency of the machine and that has a control device that operates the compressor during a cooling test run, is equipped with a detector that detects the outdoor temperature, and the control device detects this detector. An air conditioner comprising a control means for reducing the operating frequency during the cooling test operation when the outdoor air temperature is equal to or lower than a predetermined temperature. 4. A compression unit connected to the heat exchanger for refrigerant, comprising a plurality of indoor units in which a heat exchanger for refrigerant in which a refrigerant flows and a heat exchanger for hot water in which hot water flows are arranged in the same body. In an air conditioner that controls the operating frequency of the machine and that has a control device that operates the compressor during a cooling test run, an outdoor air temperature detector that detects an outdoor air temperature is provided, and the control device has this detector An air conditioner comprising control means for increasing or decreasing the operating frequency during the cooling test operation in accordance with the detected outdoor air temperature.