CN103791590A - Method for VRV air conditioner outdoor heat exchange and dispersion in refrigeration mode - Google Patents

Abstract

The invention discloses a method for dispersing outdoor heat exchange in the refrigeration mode of a VRV air conditioner. The main steps include: first connecting the inlets of the outdoor heat exchangers (3) of each outdoor unit with a connecting pipeline (2) with a ball valve (1). connected to each other; and in the cooling mode, start some of the outdoor units to run, once the pressure value of the pressure sensor (7) at the outlet of the compressor (4) of an outdoor unit is greater than 3.5MPa, turn on the high-pressure outdoor unit and the The ball valve (1) of the connection pipeline (2) between the non-started outdoor units with the shortest distance between the high-pressure outdoor units. This method can avoid insufficient heat exchange of the unit due to high outdoor temperature or dust on the surface of the outdoor heat exchanger (3).

Description

Distributed method of outdoor heat exchange in VRV air-conditioning cooling mode

technical field

The invention relates to a VRV air conditioner, that is, a multi-connected air conditioner unit, referred to as a multi-connected air conditioner, and specifically relates to a method for dispersing outdoor heat exchange in the cooling mode of a VRV air conditioner.

Background technique

The multi-connected air conditioner unit in the prior art includes a plurality of outdoor units connected in parallel, a plurality of indoor units connected in parallel, and two refrigerant circulation main pipes connecting the indoor units and the outdoor units. The multiple outdoor units connected in parallel communicate with the multiple indoor units connected in parallel through two main refrigerant circulation pipes.

Each outdoor unit includes compressor, oil separator, four-way reversing valve, outdoor heat exchanger (condenser in cooling mode) and gas-liquid separator. The outlet of the compressor communicates with one end of the oil separator, the other end of the oil separator communicates with the first valve port of the four-way reversing valve, the second valve port of the four-way reversing valve communicates with one end of the outdoor heat exchanger, and the outdoor heat exchange The other end of the device communicates with one of the two refrigerant circulation main pipes, and the other refrigerant circulation main pipe of the two refrigerant circulation main pipes communicates with the third valve port of the four-way reversing valve of each outdoor unit. The fourth valve port of the valve is connected with one end of the gas-liquid separator, and the other end of the gas-liquid separator is connected with the inlet of the compressor. The outlet of the compressor is also provided with a pressure sensor.

Each indoor unit includes an indoor electronic expansion valve and an indoor heat exchanger (evaporator in cooling mode). One end of the indoor heat exchanger is connected to one end of the indoor electronic expansion valve, and the other end of the indoor electronic expansion valve is connected to the two One of the two refrigerant circulation main pipes is connected, and the other end of the indoor heat exchanger is connected with the other refrigerant circulation main pipe of the two refrigerant circulation main pipes.

In cooling mode, the first valve port of the four-way reversing valve is connected to the second valve port, and the third valve port is connected to the fourth valve port, that is, the refrigerant flows along the compressor, outdoor heat exchanger, internal unit electronic expansion valve, The route of indoor heat exchanger and compressor circulates.

In the actual operation of the air conditioning unit, it often happens that the number of indoor units is not large and the demand for heat exchange is not very large. Under normal conditions, it is not necessary to start all the outdoor units for heat exchange, but only part of the outdoor units can be used to meet the system requirements. heat exchange requirements. However, when the outdoor temperature is high, the heat transfer effect of the outdoor heat exchanger is poor, resulting in insufficient heat transfer of the unit and failure of normal cooling. The operating temperature range of the unit is narrow and the operation reliability is poor. Moreover, after the surface of the outdoor heat exchanger is stained with dust due to long-term use, the heat exchange area of the heat exchanger will be reduced, which will also lead to insufficient heat exchange and normal cooling.

Contents of the invention

The technical problem to be solved by the present invention is to provide a method for dispersing outdoor heat transfer in VRV air conditioner cooling mode that avoids insufficient heat transfer capacity of the unit due to high outdoor temperature or dust on the surface of the outdoor heat exchanger.

The technical solution of the present invention is to provide a method for dispersing outdoor heat exchange in VRV air-conditioning refrigeration mode, and its specific steps are as follows:

a. Use connecting pipelines with ball valves to connect the inlets of the outdoor heat exchangers of each outdoor unit to each other;

b. In the cooling mode, start some outdoor units to run. Once the pressure value of the pressure sensor at the compressor outlet of a certain outdoor unit is greater than 3.5Mpa, turn on the high-pressure outdoor unit and the one with the shortest distance from the high-pressure outdoor unit. Ball valves connecting pipelines between outdoor units that are powered on;

c. The refrigerant is discharged from the compressor outlet of the high-pressure outdoor unit and then passes through the oil separator of the outdoor unit, and is divided into two streams. One stream still flows into the outdoor heat exchanger of the high-pressure outdoor unit, and the other stream flows into the unconnected pipe through the connecting pipeline. In the outdoor heat exchanger of the outdoor unit that is turned on, two streams of refrigerant flowing through two different outdoor heat exchangers join together in the same refrigerant circulation main pipe, then flow through each indoor unit, and then flow into another refrigerant circulation main pipe, and are finally sucked Return to the compressor of the high-pressure outdoor unit to complete the cycle.

Using the above method, compared with the prior art, the outdoor heat exchange dispersion method of VRV air-conditioning refrigeration mode of the present invention has the following advantages:

If the outdoor temperature is too high or the heat transfer effect of the outdoor unit is poor and the heat transfer capacity is insufficient due to the dust on the outdoor heat exchanger, the natural liquefaction of a large amount of gaseous refrigerant in the outdoor heat exchanger of the outdoor unit is insufficient, resulting in an increase in pressure. When it rises to the warning value, that is, when the pressure at the outlet of the compressor is greater than 3.5Mpa, open the connecting pipeline, which essentially makes the outdoor heat exchanger of the high-pressure outdoor unit and the outdoor heat exchanger of the outdoor unit that is not turned on be connected in parallel, and the high-pressure outdoor unit that is turned on The compressor can drive the refrigerant to flow through the two outdoor heat exchangers at the same time, so that the heat exchange area of the outdoor heat exchangers that were originally idle due to not being turned on can be utilized, that is, the number of outdoor units that are turned on can be effectively increased without increasing the number of outdoor units. The heat exchange area of the unit is enlarged, the heat exchange effect is improved, and the heat exchange capacity of the unit is increased, so that the unit can still cool normally when the outdoor temperature is high or when the heat exchanger is stained with dust, and the temperature application range of the air conditioner is expanded. Enhance the reliability of system operation; moreover, although the power of the high-pressure outdoor unit that starts up is increased, the heat exchange capacity of the unit is greatly enhanced due to the doubled heat exchange area. The ratio of heat exchange heat to compressor power is the air conditioner The energy efficiency ratio is still significantly increased.

Description of drawings

Fig. 1 is a system schematic diagram of the method for decentralized outdoor heat exchange in VRV air-conditioning cooling mode of the present invention.

As shown in the figure, 1. Ball valve, 2. Connecting pipeline, 3. Outdoor heat exchanger, 4. Compressor, 5. Oil separator, 6. Refrigerant circulation main pipe, 7. Pressure sensor.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

As shown in FIG. 1 , the method for decentralized outdoor heat exchange in VRV air-conditioning refrigeration mode of the present invention has the following specific steps.

a. Connect the inlets of the outdoor heat exchangers 3 of each outdoor unit with the connecting pipeline 2 with a ball valve 1; The inlet communicates with the inlets of the outdoor heat exchangers 3 of the other four outdoor units through the connecting pipeline 2 .

b. In the cooling mode, start some outdoor units to run. Once the pressure value of the pressure sensor 7 at the outlet of the compressor 4 of an outdoor unit is greater than 3.5Mpa, the outdoor unit is called a high-pressure outdoor unit. Turn on the high-pressure outdoor unit. The ball valve 1 of the connection pipeline 2 between the high-pressure outdoor unit and the shortest distance from the high-pressure outdoor unit.

c. The refrigerant is discharged from the outlet of the compressor 4 of the high-pressure outdoor unit and then passes through the oil separator 5 of the outdoor unit, and is divided into two streams, one still flows into the outdoor heat exchanger 3 of the high-pressure outdoor unit, and the other stream passes through the connecting pipe The path 2 flows into the outdoor heat exchanger 3 of a non-started outdoor unit with the shortest distance from the high-pressure outdoor unit. Each indoor unit then flows into another refrigerant circulation main pipe 6, and is finally sucked back to the compressor 4 of the high-pressure outdoor unit to complete the cycle.

This method essentially distributes the heat exchange process performed in a single outdoor unit to two outdoor units, hence the name outdoor heat exchange dispersion.

Claims (1)

1. a VRV air-conditioning refrigeration mode outdoor heat transfer dispersion method, is characterized in that: its specific steps are as follows: a. Connect the inlets of the outdoor heat exchangers (3) of each outdoor unit with the connecting pipes (2) with ball valves (1); b. In the cooling mode, start some outdoor units to run. Once the pressure value of the pressure sensor (7) at the outlet of the compressor (4) of an outdoor unit is greater than 3.5Mpa, turn on the high-pressure outdoor unit and the high-pressure outdoor unit. The ball valve (1) of the connecting pipeline (2) between the unstarted outdoor unit with the shortest distance from the unit; c. The refrigerant is discharged from the outlet of the compressor (4) of the high-pressure outdoor unit and then passes through the oil separator (5) of the outdoor unit, and is divided into two streams. One still flows into the outdoor heat exchanger (3) of the high-pressure outdoor unit. The other stream flows into the outdoor heat exchanger (3) of the unstarted outdoor unit through the connecting pipe (2), and the two streams of refrigerant flowing through two different outdoor heat exchangers (3) are in the same refrigerant circulation main pipe (6). Then flow through each indoor unit, then flow into another refrigerant circulation main pipe (6), and finally be sucked back to the compressor (4) of the high-pressure outdoor unit to complete the cycle.

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