CN1616902A - Multi-room air conditioner - Google Patents

Abstract

The present invention relates to a multiroom-type air conditioner capable of performing the comfortable reheating dehumidifying operation at low cost without enlarging an outdoor machine when the number of indoor machines to be connected is increased. An outdoor machine is connected to a plurality of indoor machines to carrying out cold air operation, heating operation and reheating dehumidifying operation. In this multiroom-type air conditioner constituted by connecting a plurality of indoor machines having the indoor heat exchangers where a first heat exchanger and a second heat exchanger are connected through flow path adjusting means, and capable of performing the reheating dehumidifying operation, with the outdoor machine comprising a compressor, a four-way valve, an outdoor heat exchanger, an outdoor fan for sending the air to the outdoor heat exchanger, and a plurality of outdoor restriction devices, the second heat exchanger is constituted to be located at an upstream side of the refrigerant flow of the first heat exchanger in heating cycle, and the heat exchanging capacity of the second heat exchanger is higher than that of the first heat exchanger.

Description

Multi-room air conditioner

technical field

The present invention relates to a multi-room air conditioner that connects multiple indoor units to one outdoor unit and can perform cooling operation, heating operation, and reheating and dehumidification operation. A multi-room air conditioner combined with a multi-unit operation expansion operation method.

Background technique

Among the multi-room air conditioners that connect multiple indoor units to one outdoor unit and perform cooling operation and heating operation without mixing simultaneously, but perform cooling operation or heating operation, air conditioners that perform dehumidification operation during heating operation are listed in JPKP Publication No. 11-304286. This technique is to install a bypass circuit equipped with a decompression device for bypass branching from the middle of the pipeline of the outdoor heat exchanger, and connect this bypass circuit to multiple decompression devices for cooling and heating and the indoor heat exchanger. between. By setting this bypass circuit, each indoor unit can freely select the air-conditioning and heating functions and the dehumidification functions, so that the air-conditioning operation and the dehumidification operation can be operated at the same time, and the heating operation and the dehumidification operation can be operated at the same time. Therefore, a multi-room air conditioner excellent in comfort can be provided. FIG. 3 shows the cold air cycle of this multi-room air conditioner in the prior art.

In the two-chamber air conditioner shown in FIG. 3 , when both chambers are in cooling operation, the high-temperature and high-pressure gaseous cold medium blown from the compressor 1 flows through the four-way valve 2 to the outdoor heat exchanger 3 . The gas refrigerant exchanges heat with the atmosphere in the outdoor side heat exchanger 3 and condenses to become a high-pressure liquid refrigerant. The liquid refrigerant branched from the refrigerant pipes 10a, 10b is decompressed by the electric expansion valves 4a, 4b for cooling and heating. The cold medium passes through the first indoor heat exchanger 5a and the second indoor heat exchanger 6a of the indoor unit A, and the first indoor heat exchanger 5b and the second indoor heat exchanger 6b of the indoor unit B to cool the air in the two rooms. The medium evaporates and becomes a low-temperature and low-pressure gaseous cold medium, which returns to the compressor 1 through the four-way valve 2.

At this time, the dehumidification electric expansion valve 15a of the indoor unit A and the dehumidification electric expansion valve 15b of the indoor unit B are fully opened, and the pressure loss is small, and the bypass electric expansion valves 14a and 14b of the bypass circuits 13a and 13b are fully closed. . In addition, when only one room of the indoor unit A or the indoor unit B is cooled, one of the air-conditioning and heating electric expansion valves 4a or 4b is closed, and only one room is cooled.

On the other hand, when the dehumidification operation is performed simultaneously in both chambers, the electric expansion valves 4a and 4b for air conditioning and heating are fully closed, and the electric expansion valves 15a and 15b for dehumidification are turned down to reduce the pressure of the refrigerant. As a result, each of the first indoor heat exchangers 5a and 5b functions as a condenser and functions as a reheater, and each of the second indoor heat exchangers 6a and 6b functions as an evaporator. Therefore, the air is dehumidified without being cooled, and is blown out from each indoor unit.

In addition, during this dehumidification operation, in order to increase the capability of the first indoor heat exchangers 5a and 5b as reheaters, control is performed to decrease the rotational speed of the outdoor side air blower 12 .

Furthermore, in order to increase the capacity of the first indoor heat exchangers 5a, 5b as reheaters, the electric expansion valves 4a, 4b for air conditioning and heating are largely turned down, and at the same time, the electric expansion valves for bypass are greatly opened. 14a, 14b, thereby increasing the amount of the gas-liquid double-layered cold medium sent to the first indoor heat exchanger 5a, 5b to increase the reheat.

In addition, the case where the air-conditioning operation of the indoor unit A and the dehumidification operation of the indoor unit B is performed is as follows. That is, on the indoor unit A side, while the electric expansion valve 4a for cooling and heating in the circuit through which the cold medium flows acts as a pressure reducer, if the electric expansion valve 15a for dehumidification is fully opened and the electric expansion valve for bypass is fully closed 14a, the first indoor heat exchanger 5a and the second indoor heat exchanger 6a of the indoor unit A function as evaporators to supply the indoor A with cool air. On the other hand, on the side of the indoor unit B, the air-conditioning and heating electric expansion valve 4b of the circuit through which the cold medium flows is screwed to nearly fully closed, the bypass electric expansion valve 14b is fully opened, and the dehumidification electric expansion valve 15b is screwed down. It functions as a pressure reducer. As a result, since the first indoor heat exchanger 5b of the indoor unit B functions as a condenser and the second indoor heat exchanger 6b functions as an evaporator, dehumidification can be performed without cooling the air on the side of the indoor unit B.

Next, when both rooms are in heating operation, the high-temperature and high-pressure gas refrigerant blown out from the compressor 1 passes through the four-way valve 2 and flows to the second indoor heat exchanger 6a and the first indoor heat exchanger 5a of the indoor unit A. And the second indoor heat exchanger 6b and the first indoor heat exchanger 5b of the indoor unit B. Here, it exchanges heat with the indoor air and condenses to become a high-pressure liquid cold medium. The liquid cold medium is decompressed through the electric expansion valves 4a and 4b for air-conditioning and heating, and the outdoor heat exchanger 3 exchanges heat with the atmosphere to absorb heat. The cold medium evaporates and becomes a low-temperature and low-pressure gas cold medium. compressor 1.

At this time, the dehumidification electric expansion valve 15a of the indoor unit A and the dehumidification electric expansion valve 15b of the indoor unit B are fully opened, and the bypass electric expansion valves 14a and 14b of the bypass circuits 13a and 13b are fully closed.

In addition, for example, when only the indoor unit B performs heating operation, stop the blower 9a of the indoor unit A, and close the electric expansion valve 4a for cooling and heating to a large extent to the extent that the cold medium does not flow through, so that only the indoor air can be heated. The room that the air blower 9b of machine B operates sends heating.

In addition, when the indoor unit B is made to perform the heating operation, and the indoor unit A is operated to perform the dehumidification operation, the operation is as follows. On the indoor unit B side, the electric expansion valve 4b for air conditioning and heating of the circuit through which the cold medium flows acts as a pressure reducer, and at the same time, the electric expansion valve 15b for dehumidification can be fully opened and the electric expansion valve 14b for bypass can be fully closed. In addition, the electric expansion valve 4a for cooling and heating on the side of the indoor unit A is fully opened, and the electric expansion valve 15a for dehumidification functions as a pressure reducer. As a result, the second indoor heat exchanger 6a of the indoor unit A functions as a reheater, the first indoor heat exchanger 5a functions as an evaporator, and dehumidification can be performed without cooling the indoor air.

However, in the above-mentioned prior art structure, a bypass circuit branched from the middle of the pipeline of the outdoor heat exchanger and a pressure reducing device for the bypass are required when performing the reheating and dehumidification operation, and there is a problem of increased cost.

Furthermore, when increasing the number of connected indoor units, it is necessary to install as many bypass circuits as the number of connected units, so there is a problem of increasing the size of the outdoor unit in order to secure space.

In addition, when the reheating and dehumidification operation is performed without installing a bypass circuit, there are the following problems. In other words, when the outside air temperature is very low like in winter, or when the cooling operation is being performed in another room, and the speed of the outdoor fan cannot be reduced to ensure the cooling capacity, etc., because the heat dissipation of the outdoor heat exchanger is large, There is a problem that the room temperature of the room where the dehumidification operation is performed falls.

Contents of the invention

The present invention is proposed to solve the problems existing in the prior art, and its purpose is to provide a multi-room air conditioner, which does not require a bypass circuit, can save space, and can realize room temperature without lowering at a low cost. Comfortable reheat dehumidification operation.

The multi-room air conditioner of the present invention is formed by connecting an outdoor unit with a plurality of indoor units. The outdoor unit has a compressor, a four-way valve, an outdoor heat exchanger, an outdoor fan for ventilating the outdoor heat exchanger, and a plurality of outdoor nodes The air flow device, the indoor unit has an indoor heat exchanger connected to the first heat exchanger and the second heat exchanger through the flow path adjustment device, and can perform reheating and dehumidification operation, and the structure of the multi-room air conditioner is as follows: The configuration of the second heat exchanger is such that it is on the upstream side of the cold medium flow of the first heat exchanger when the heating cycle is running, and the heat exchange capacity of the second heat exchanger is greater than that of the first heat exchanger.

With such a structure, it is not necessary to install a bypass circuit equipped with a bypass decompression device connected between a plurality of air-conditioning and heating decompression devices and the indoor heat exchanger. The outdoor unit can be enlarged by using the space of the air circuit, and the comfortable reheating and dehumidification operation can be realized at a low cost.

Description of drawings

Fig. 1 is a cooling air circulation diagram of a multi-room air conditioner according to Embodiment 1 of the present invention.

Fig. 2 is a cooling air circulation diagram of a multi-room air conditioner according to Embodiment 2 of the present invention.

Fig. 3 is a cold air circulation diagram of a conventional multi-room air conditioner.

Detailed ways

Embodiments of the present invention will be described below with reference to the drawings. In the multi-room air conditioner described in this embodiment, a plurality of indoor units are connected in parallel to one outdoor unit. Here, a case where two indoor units A and B are connected will be described.

Example 1

Fig. 1 is a cooling air circulation diagram of a multi-room air conditioner according to Embodiment 1 of the present invention. When running under the cold air cycle, the cold medium flows in the direction of the solid arrow in Figure 1. The cold medium blown out from the compressor 1 is condensed by the outdoor heat exchanger 3, then decompressed by the electric expansion valves 4a and 4b for air conditioning and heating, and passes through the first indoor heat exchanger 5a and the second indoor heat exchanger of the indoor unit A. 6a and the first indoor heat exchanger 5b and the second indoor heat exchanger 6b of the indoor unit B, and return to the compressor 1. At this time, the temperature of the room to be regulated is lowered by the heat absorbed when the cooling medium evaporates in each of the indoor heat exchangers 5a, 6a, 5b, and 6b.

In addition, the cold medium flow when running under the heating cycle is in the direction of the dotted arrow in Figure 1, which is opposite to that of the cold air, and passes through the heat exchangers 5a, 6a of the indoor unit A and the indoor heat exchangers 5b, 6b of the indoor unit B. The heat released when the cold medium condenses raises the temperature of the room to be conditioned.

There are two adjustment types for the amount of cold medium blown out, one is to adjust by adjusting the operation and stop of the compressor 1, and the other is to adjust not only that but also by changing the speed of the compressor 1. The electric expansion valves 4a and 4b for air conditioning and heating are installed in the cooling medium circuit corresponding to the heat exchangers of multiple indoor units, and the decompression and the cooling medium flowing to each indoor heat exchanger 5a and 5b are adjusted by adjusting the opening degree. flow.

In such an air-conditioning cycle, when the reheating and dehumidification operation is performed in the air-conditioning cycle, when the atmospheric temperature is low during winter, since the amount of heat discharged to the atmosphere at the outdoor heat exchanger 3 is large, even if the outdoor blower 12 As the rotation speed decreases, the capacity of the reheaters as the first indoor heat exchangers 5a and 5b becomes insufficient, and the room temperature also decreases.

In addition, when indoor unit B performs dehumidification operation while indoor unit A is in air-cooling operation, when the rotation speed of outdoor blower 12 decreases, the cooling capacity of indoor unit A cannot be ensured due to the reduction of the heat exhausted by outdoor heat exchanger 3 . In response to this point, if a bypass circuit structure such as the above-mentioned prior art example is installed, the cost will increase on the one hand, and at the same time, the number of connected indoor units will increase. In order to ensure the bypass circuits 13a, 13b space, the outdoor unit must be enlarged.

Therefore, in Embodiment 1 of the present invention, the indoor unit A has the first indoor heat exchanger 5a and the second indoor heat exchanger 6a, and the indoor unit B has the first indoor heat exchanger 5b and the second indoor heat exchanger 6b . Furthermore, the connections between the first indoor heat exchangers 5a, 5b and the second indoor heat exchangers 6a, 6b are composed of capillary tubes 7a, 7b as flow path adjustment devices and on-off valves 8a, 8b as bypass devices. The flow path adjustment device 7.

In addition, among the indoor heat exchangers, the second indoor heat exchanger 6a of the indoor unit A and the second indoor heat exchanger 6b of the indoor unit B are constructed so that they are relatively opposite to the first indoor heat exchanger of the indoor unit A during heating cycle operation. The heat exchanger 5a and the first indoor heat exchanger 5b of the indoor unit B become the upstream side of the cold medium flow; moreover, it is structured such that the heat exchange capacity of each of the second indoor heat exchangers 6a, 6b is higher than that of the first indoor heat exchanger. 5a, 5b have greater heat exchange capacity.

By switching the four-way valve 2, the dehumidification operation can be performed even in any of the occasions of the cooling cycle operation and the heating cycle operation.

Next, the case where the reheating and dehumidification operation is performed during the air-cooling cycle operation in Embodiment 1 of the present invention will be described. The flow direction of the cold medium is indicated by the solid arrows in FIG. 1 . The cold medium blown out from the compressor 1 is branched into cold medium pipelines 10a and 10b through the outdoor heat exchanger 12, and circulates in the following order: electric expansion valves 4a and 4b for air conditioning and heating, first indoor heat exchangers 5a and 5b, flow Path regulating device 7 (capillary tube 7a, 7b and switch valve 8a, 8b as its bypass device), second indoor heat exchanger 6a, 6b, cold medium pipeline 11a, 11b, compressor 1. At this time, the electric expansion valves 4a and 4b for air conditioning and heating are fully opened, the on-off valves 8a and 8b of the flow path regulating device 7 are closed, and the cooling medium flows through the capillary tubes 7a and 7b through throttling, so that the first indoor heat exchanger 5a, 5b functions as a condenser, and the second indoor heat exchangers 6a and 6b function as evaporators, and perform reheating and dehumidification operation.

At this time, in the present invention, since the structure is such that the heat exchange capacity of the second indoor heat exchangers 6a, 6b functioning as evaporators is higher than that of the first indoor heat exchangers 5a, 5b functioning as condensers, The exchange capacity is larger, so dehumidification operation can be performed with a large drop in humidity.

In the following, when one room is cooling and the other room is dehumidifying, the case where indoor unit B performs cooling operation and indoor unit A performs reheating and dehumidifying operation will be described as an example. The on-off valve 8b of the indoor unit B is opened, and the electric expansion valve 4b for air-conditioning and heating is moderately turned down. The on-off valve 8a of the indoor unit A for reheating and dehumidification is closed, the capillary 7a is used to depressurize, and the electric expansion valve 4a for cooling and heating is fully opened. By controlling each valve in this way, in the indoor unit B, the first indoor heat exchanger 5a and the second indoor heat exchanger 5b function as evaporators. On the other hand, in the indoor unit A, the first indoor heat exchanger 5b functions as a condenser, and the second indoor heat exchanger 6b functions as an evaporator. As a result, the cooling operation can be performed in the indoor unit A, and the dehumidification operation can be performed in the indoor unit B with the humidity greatly reduced.

Next, a case where the reheating and dehumidification operation is performed during the heating cycle operation will be described. The flow direction of the cooling medium is indicated by the dashed arrows in FIG. 1 . The cold medium blown out from the compressor 1 is branched at the cold medium pipeline 11a, 11b, and circulates in the following order: the second indoor heat exchanger 6a, 6b, the flow path adjustment device 7 (capillary tube 7a, 7b and as its bypass device On-off valve 8a, 8b), the first indoor heat exchanger 5a, 5b, electric expansion valve 4a, 4b for air conditioning and heating, cold medium pipeline 10a, 10b, outdoor heat exchanger 12, compressor 1.

At this time, the on-off valves 8a and 8b of the flow path adjustment device are closed, and the cold medium flows through the capillary tubes 7a and 7b to make it play a throttling role. The exchangers 6a, 6b function as condensers, and the first indoor heat exchangers 5a, 5b function as evaporators, enabling reheating and dehumidification operation.

In addition, at this time, the present invention is adopted because it is structured such that the heat exchange capacity of the second indoor heat exchangers 6a, 6b functioning as condensers is higher than that of the first indoor heat exchangers 5a, 5b functioning as evaporators. Since the exchanging capacity is larger, even in winter when the atmospheric temperature is low, the amount of heat released by the second indoor heat exchangers 6a, 6b can be sufficiently ensured, and a drop in room temperature can be prevented.

Hereinafter, a case where one room is heated and the other room is dehumidified will be described as an example where the indoor unit B performs the heating operation and the indoor unit A performs the reheating and dehumidifying operation. The on-off valve 8b of the indoor unit B is opened, and the electric expansion valve 4b for air-conditioning and heating is moderately turned down. The on-off valve 8a of the indoor unit A for reheating and dehumidification is closed, the capillary 7a is used to depressurize, and the electric expansion valve 4a for cooling and heating is fully opened. When the respective valves are controlled in this way, the first indoor heat exchanger 5a and the second indoor heat exchanger 5b of the indoor unit A function as condensers. On the other hand, the second indoor heat exchanger 6b of the indoor unit B functions as a condenser, and the first indoor heat exchanger 5b functions as an evaporator. As a result, the heating operation can be performed in the indoor unit A, and the reheating and dehumidifying operation can be performed in the indoor unit B without cooling the indoor air.

In this way, according to Embodiment 1 of the present invention, it is not necessary to install a bypass decompression device and a bypass circuit, and even if the number of connected indoor units increases, the outdoor unit will not be enlarged, and comfortable reheating and dehumidification operation can be performed at low cost. .

In addition, although the case where two indoor units were connected was demonstrated in this Example, even when connecting three or more indoor units, it can implement similarly.

Example 2

Fig. 2 is a cooling air circulation diagram of a multi-room air conditioner according to Embodiment 2 of the present invention. Between the first indoor heat exchanger 5a and the second indoor heat exchanger 6a of the indoor unit A, and the first indoor heat exchanger 5b and the second indoor heat exchanger 6b of the indoor unit B, between 5b and the second indoor heat exchanger The flow path adjustment device provided between the exchangers 6a, 6b makes the flow rate variable. Since the other structures are the same as those in Embodiment 1, description thereof will be omitted. That is, in Example 1, although the on-off valves 8a, 8b and the capillary tubes 7a, 7b are arranged in parallel between the first indoor heat exchangers 5a, 5b and the second indoor heat exchangers 6a, 6b, in Example 2 In the reheating and dehumidification operation, electric expansion valves 15a and 15b for dehumidification that can adjust the flow rate are installed as flow path adjustment devices.

With such a structure, the capacity of the condenser and the evaporator can be adjusted by adjusting the throttling flow rate of the flow path adjustment device, thereby achieving the effect of performing comfortable reheating and dehumidification operation at low cost.

In addition, Table 1 shows the operations of the air-conditioning and heating electric expansion valves 4 a and 4 b and the dehumidification electric expansion valves 15 a and 15 b for each operation mode combination.

Table 1

Cooling cycle operation + dehumidification operation Operation mode Expansion valve Indoor unit A Indoor unit B Expansion valve 4a Expansion valve 4b Expansion valve 15a Expansion valve 15b dehumidification stop fully open fully closed Twist small fully open dehumidification air supply fully open fully closed Twist small fully open dehumidification Heating not run dehumidification air conditioner fully open Twist small Twist small fully open dehumidification dehumidification fully open fully open Twist small Twist small

Heating cycle operation + dehumidification operation Operation mode Expansion valve Indoor unit A Indoor unit B Expansion valve 4a Expansion valve 4b Expansion valve 15a Expansion valve 15b dehumidification stop fully open stop screwing small Twist small fully open dehumidification air supply fully open fully closed Twist small Twist small dehumidification Heating fully open Twist small Twist small fully open dehumidification air conditioner not run

Example 3

The cold air cycle diagram of the multi-room air conditioner in Embodiment 3 of the present invention is shown in Fig. 1 in Embodiment 1. In Embodiment 3, as shown in Fig. 1, an external device for detecting the atmospheric temperature is installed in the outdoor unit. Air temperature sensor 16. Other structures are the same as those in Embodiment 1, and their descriptions are omitted.

When the multi-room air conditioner starts to operate from a stopped state, the selected reheating and dehumidification operation is selected based on the temperature detected by the outside air temperature sensor 16 to operate under the cooling cycle.

That is, if the detected atmospheric temperature is higher than a predetermined temperature, the cooling cycle operation is performed; if it is lower than the predetermined temperature, the dehumidification operation is performed under the heating cycle. For example, by setting the specified temperature to 30°C, the range of dehumidification operation under the heating cycle can be expanded.

In this way, if a predetermined temperature of about 30°C is set, when the atmospheric temperature is lower than this temperature, the dehumidification operation can be performed without lowering the room temperature because the reheating and dehumidification operation is performed under the heating cycle. Conversely, when the air temperature is above 30°C and a large cooling capacity is required, since the reheating and dehumidification operation is performed under the air-cooling cycle, the dehumidification operation can be performed to greatly reduce the humidity, and the comfortable dehumidification operation can be performed at low cost.

Example 4

The cold air circulation diagram of the multi-room air conditioner according to Embodiment 4 of the present invention is the same as that in FIG. 1 of Embodiment 1. FIG. In Embodiment 4, when the multi-room air conditioner starts to operate from the stopped state, the operation when the reheat and dehumidify operation is selected is to perform the reheat and dehumidify operation under the heating cycle operation. With such a structure, since the reheating and dehumidification operation is performed during the heating cycle operation, dehumidification can be performed without lowering the room temperature, and the range of the comfortable reheating and dehumidification operation without lowering the room temperature can be expanded at low cost.

Example 5

The cold air circulation diagram of the multi-room air conditioner according to the fifth embodiment of the present invention is the same as that of FIG. 1 of the first embodiment. In Example 5, when a certain indoor unit selects the reheating and dehumidification operation, and when another room is performing cooling operation, the reheating and dehumidification operation is performed under the cooling air cycle as it is; while the other room is performing heating operation. In other cases, the reheating and dehumidification operation is carried out under the heating cycle as it is. With such a structure, the reheating and dehumidification operation can be performed regardless of the operation mode of other rooms, and a comfortable and excellent multi-room air conditioner can be provided at low cost.

As mentioned above, even if the number of connected indoor units is increased, the multi-room air conditioner of the present invention does not increase the number of outdoor units, and can perform comfortable reheating and dehumidification operation without lowering the room temperature at low cost. Air conditioner for business use.

Claims (5)

1. multi-room air conditioner, described multi-room air conditioner connects and composes by an off-premises station and many indoor sets, and described off-premises station has compressor, cross valve, outdoor heat converter, gives the outdoor fan of described outdoor heat converter ventilation and the outdoor throttling arrangement that is provided with corresponding to many indoor sets that connected; The stream adjusting device that described indoor set has by switching the connected sum decompression at least connects first indoor heat converter and second indoor heat converter, can carry out heat dehumidifying operation again; It is characterized in that, the structure of described multi-room air conditioner is, the configuration of described second indoor heat converter makes it be in the upstream side of the cold MEDIA FLOW of described first indoor heat converter when heating installation circular flow, and the heat-exchange capacity of described second indoor heat converter is bigger than the heat-exchange capacity of described first indoor heat converter.

2. multi-room air conditioner as claimed in claim 1 is characterized in that the flow of stream adjusting device is variable.

3. multi-room air conditioner as claimed in claim 1, it is characterized in that, has the atmospheric temperature checkout gear that detects atmospheric temperature, atmospheric temperature when when selecting heat dehumidifying operation again, detecting heat dehumidifying operation beginning again, if time operation circulating cold air that detected atmospheric temperature is higher than set point of temperature, if beginning heat dehumidifying operation again under heating installation circulation when lower than set point of temperature.

4. multi-room air conditioner as claimed in claim 1 is characterized in that, when selecting heat dehumidifying operation again when air conditioner brings into operation, carries out heat dehumidifying operation again under the heating installation circulation.

5. multi-room air conditioner as claimed in claim 1, it is characterized in that, when at least one indoor set requires heat dehumidifying operation again, carried out the occasion of cold air operation at other indoor set and under circulating cold air, carried out heat dehumidifying operation again, under the heating installation circulation, carried out heat dehumidifying operation again in the occasion of carrying out the heating installation operation.

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