Heat and cold transfer in the air conditioner is carried out by means of a refrigerant (freon, freon). In semi-industrial and domestic systems, R22 and R410a freons are used. The work efficiency depends on the pressure level in the air conditioner system. How to measure it and is there a dedicated air conditioner pressure control valve?
Air conditioner pressure parameters
Finding the pressure in the air conditioner is very simple. The information should be indicated on the outdoor unit. Pressure readings are objective only for equipment of the same model. Different models from the same manufacturer can operate at different pressures. The parameters depend on the type of compressor, power.
The table gives the upper indicators of high and low pressure in the air conditioning system:
- discharge side - high pressure side, here the freon after passing through the compressor is in the liquid fraction;
- suction side- low pressure side. In the evaporator, freon becomes gaseous.
The refrigerant pressure level in the system is controlled only by manual top-up or manual bleeding. There are no special pressure valves in household air conditioners (unlike auto air conditioners).
How to check pressure
To control the pressure in the air conditioner, use a gauge station.
They are available for various types of refrigerant. The station consists of two pressure gauges: blue and red, they are connected to the manifold and through hoses to the freon line.
When the air conditioner is started in cooling mode, the blue low pressure gauge checks the air conditioner pressure at the inlet of the freon line to the outdoor unit.
The red pressure gauge measures high pressure. It should be connected to the outlet of the freon line from the compressor, that is, on the discharge side.
To connect the pressure gauge, special flexible hoses are used, which are connected with an external nut to the service valve. Look for it in the place where the thick copper pipe is attached to the outdoor unit. After connecting, the air conditioner starts and after a quarter of an hour you can check the air conditioner freon pressure on the pressure gauge. It must be remembered that during periods when the compressor is off, the readings are not correct.
Working pressure and air temperature
Working pressure is closely related to the ambient temperature.
So, when the air temperature in a room or outdoors rises by 5 degrees, the working pressure should be increased by approximately 0.5 bar for R410a freon.
For freon R22, the dependence of the operating pressure in the air conditioner on the temperature outside and in the room is different. The exact numbers can be found in special tables.
