Two-Stage Oil Rotary Vane Pump in air conditioning vacuum pumping

For air conditioning, vacuumizing is an essential and important process before filling refrigerant in the process of air conditioning production, installation and maintenance. The specific method is to connect the vacuum pump with the air conditioning system pipeline to remove the non condensable gas and moisture in the air conditioning system pipeline.

Brief introduction of air conditioning vacuum pumping

1. After the vacuum pump is started, the non condensable gas and water vapor in the air conditioning system are first extracted, and then only water molecules (liquid) are left.

2. With the increase of vacuum degree, the absolute pressure in the air conditioning system decreases. When the absolute pressure in the system decreases to the saturated steam pressure corresponding to the ambient temperature, the remaining water molecules in the system boil into water vapor and are continuously extracted It should be noted that in the process of vacuum pumping, the temperature in the system is consistent with the ambient temperature under normal operation.

Vacuumizing effect of air conditioner

1. Remove the non condensable gas in the system

The existence of non condensable gas will increase the condensing pressure and exhaust temperature of the system, which will affect the refrigeration effect; it may also cause the lubricating oil to carbonize at high temperature, endanger the normal operation of the compressor, and even burn out the compressor motor.

2. Remove moisture from the system

As we all know, there are a lot of nitrogen, oxygen, carbon dioxide and other gases in the air, which can not be dissolved into the refrigerant. We usually call them non condensable gases. In addition, the water in the air and refrigerant are not mutually soluble. The existence of water and non condensable gas affects the operation effect of air conditioning, so the purpose of vacuum pumping is to remove the non condensable gas and water in the air conditioning system.

Moisture is the biggest killer in the refrigeration system (especially the Freon system in the vapor compression refrigeration cycle). First of all, the interaction between lubricating oil and water will generate acid, which will corrode the system, and at the same time, it will cause “copper plating” phenomenon and damage the compressor; at the same time, water will cause ice formation in the expansion valve port or capillary tube, resulting in “ice blockage”.

Two ways of air conditioning vacuum pumping

The first is vacuumizing, and the second is external air evacuation.

1. Vacuumizing method: after the air conditioner is installed, it is a method to exhaust the air in the air conditioning copper pipe pipeline and the internal and external unit system. It needs to use the vacuum pump to remove the air inside.

2. External air evacuation method: after the installation of the air conditioner, use the refrigerant carried by the external unit of the air conditioner to push out the air inside the copper pipe line and the internal unit, so as to achieve the purpose of discharging air.

Under what conditions should vacuum be pumped?

1. Air conditioning production process. The outdoor unit of air conditioner needs to be filled with enough refrigerant before leaving the factory, so it is necessary to vacuum the outdoor unit before charging. In addition, the on-line pipe and the refrigeration pipeline of the indoor unit need to be filled with nitrogen for anti-oxidation protection before leaving the factory, and it is also necessary to first vacuum and then inject nitrogen.

Air conditioning manufacturers in the air conditioning production process, there are strict requirements for vacuum standards to ensure the quality of products. Because the absolute vacuum of the air conditioning system is difficult to achieve, it is generally necessary to pump the gauge pressure of the air conditioning system below 30Pa to charge refrigerant.

2. Air conditioning installation process. The indoor unit, on-line pipe and outdoor unit of the air conditioner produced by the factory are all packed independently, so the nitrogen in the indoor unit and on-line pipe should be extracted completely during installation.

It should be noted that in the process of vacuum pumping, the temperature in the system is consistent with the ambient temperature under normal operation. This is also the reason why the lower the ambient temperature is, the more difficult it is to vacuum and the slower the speed is.

Application of EVP series rotary vane vacuum pump in air conditioning

EVP series small oil lubricated rotary vane vacuum pump product model: EVP175 / 275

EVP series oil lubricated vane vacuum pump

EVP series small oil lubricated rotary vane vacuum pump product parameters:

EVP series rotary vane vacuum pump features and advantages:

EVP double stage oil lubricated vane vacuum pump is famous for its high vacuum degree, fast pumping speed and strong steam treatment ability. The direct coupled rotary vane vacuum pump has compact structure, no vibration, equipped with hand injury proof fan and coupling shell to ensure safe operation.

1. Low noise: because we have done a lot of research on the drive system and motor, the noise level of EVP series products is very low, and the noise level is only half of that of traditional pumps.

2. Excellent pumping performance: EVP series products can obtain very high limit vacuum no matter in high vacuum or large displacement working mode. This unique performance enables users to choose the best performance for their application without affecting the application.

3. High flexibility: in the high vacuum working mode, EVP series products are very suitable for analytical instruments, electron microscopy, physical research turbine molecular pump front stage and leak detection. It can be used in distillation, pre stage of vacuum steam pump in laboratory, solvent concentration, freeze-drying and other drying applications.

4. Easy to use: it is very convenient to use the mode selection switch to switch the working mode. The vacuum pump can be operated at any time, including the vacuum valve.