How to solve the low pressure failure during the operation of the chiller?

The chiller belongs to industrial machinery and equipment. The development of science and technology has also made the chiller smart. If a chiller fails, a fault code will generally appear. Today, the low-pressure malfunction of the chiller is analyzed and solved.

What will the low-pressure failure of the chiller cause?

   1. Increased energy consumption

As the compressor runs at low pressure and no-load, the motor load will be reduced. Under the same cooling conditions, a chiller with a low pressure failure will waste electrical energy.

   2. The cooling capacity becomes smaller

Because the suction pressure of the chiller becomes low, but the return air volume is small, the cooling capacity will not reach the target cooling, which affects normal use.

What are the reasons for the low pressure of the chiller? How to solve it?

How to solve the low pressure failure during the operation of the chiller?

How to solve the low pressure failure during the operation of the chiller?

  No.1 refrigerant shortage or leakage

Insufficient refrigerant will cause the pressure in the system to be abnormal, resulting in a decrease in suction pressure, low-pressure alarm of the chiller, and equipment shutdown. The leakage of refrigerant can be from the compressor, condenser, filter, expansion valve and evaporator, etc. Diagnose the connection of the fittings and pipes. After troubleshooting, fill the appropriate amount of refrigerant to solve the problem. If you don’t understand the operation during this process, please contact the chiller manufacturer.

  No.2 The outside temperature is low

The outside temperature is low, and the cooling water is turned on at low temperature; or the temperature of the refrigerating oil is too low, and the refrigerator cannot be completely separated, which will cause a low pressure failure. If the cooling water temperature is too low, the cooling tower can be closed or the cooling water can be throttled to increase the cooling water temperature. If the temperature of the refrigerating oil is too low, the warm-up time of the chiller can be extended, and the temperature of the refrigerating oil can return to normal.

  No.3 system pipe is blocked

When the chiller is assembled, it is inevitable that impurities will seep into the system. After long use, various impurities will enter the system. At this time, the filter is blocked, the refrigerant throughput is reduced, the return air volume is reduced, and a low pressure failure occurs.

The solution is to clean the filter, condenser, and evaporator to ensure that the system is not clogged, and the low pressure failure caused by the clogging of the system pipeline can be eliminated.

   No. 4 expansion valve is too small or damaged

Expansion valve is the throttling device of the refrigeration system. If it is too small, it will produce a smaller refrigeration capacity, and if the refrigeration vapor is too little through throttling, it will cause the compressor intake pressure to decrease and cause low pressure failure.

The solution is to increase the opening of the expansion valve appropriately or replace the damaged expansion valve.

  No.5 relay failure, electrical system false alarm

Relay plays the role of indirect protection equipment. Generally, the normal suction pressure of the compressor is 0.4~0.6MPa. When the suction pressure is lower than 0.2MPa, it will cause the low-voltage protection relay to act, cut off the system circuit, and the equipment stops. Sometimes the low-voltage relay will malfunction due to humidity, open circuit, etc., and the system will report low voltage.

Solution, check the low-voltage relay, repair or replace, non-technical personnel can contact the manufacturer for assistance.

Normally used chillers report low-pressure faults, generally based on the above reasons. According to the system fault phenomenon, step-by-step investigation is helpful to quickly find the cause of the fault and resume normal production as soon as possible. When there is a low-pressure failure of the chiller, you can contact the chiller manufacturer for assistance.

Geson chiller product range covers Industrial Refrigeration and Commercial Central air-conditioning, including Water-cooled chillers, Air-cooled chillers, Screw chillers, Scroll chillers, Centrifugal chillers, Water(ground) source heat pumps, Air source heat pumps and etc., Capacity from 2tons~4000tons, and temperature from -160℃~30℃, complete full product series for customers.

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