1.Cooling system leak
There are leaks in the connecting pipes of the cooling system,such as welding point leakage, corrosion leakage, fracture caused by mechanical vibration,and human factors, etc. These will leads to malfunction of low pressure.
First of all, use leakage detection liquid (soap water, or detergent mixed with water) or halogen leak detector to find the leakage point. After the leakage point is found, repair it with welding equipment,then pressure holding to test leak and vacuum pumping before charging refrigerant according to the manufacturer's specifications, the chiller can resume normal operation.
2.Cooling system blockage
A. Blockage By impurities
If the filter is blocked due to dirt, it will only cause the cooling capacity drop slightly, and you may not even feel any affected.When the filter is slightly clogged, there will be a temperature difference of the inlet and outlet of the filter, which can be felt by holding the inlet and outlet with your hand.When it is block seriously, the filter will dew or frost. If there is dew or frost (except the dew after the chiller stop running under normal operation), it can be judged that the filter is block.
Replace the filter of same model
The water in the system runs with the refrigerant to the throttle valve (expansion valve). After throttling expansion, freeze at throttle outlet, thus blocking the throttle valve (expansion valve) and lead to a low-pressure fault.
Change the filter with same model.
C.Expansion Valve Damaged
Expansion valve is affected by environment in the process of using. There is corrosive gases that will corrode the liquid in some environments,which will corrode the expansion valve.
Replace new expansion valve of same model
3. Heating exchange of evaporator is seriously in sufficient.
A.Insufficient water flow in the evaporator
The water pump is broken or something bad enter in to the pump impellers,appear leakage in the water inlet pipes of water pump,(It is difficult to check, needs careful analysis),which are resulting in insufficient water flow.
Replace water pump. Or disassemble the water pump to clear the bad something in the impellers.
B.Evaporator is blocked by bad something
Firstly, you must eliminate the problem of the water pump. When the equipment is normal, there will not be a lot of condensed water,frostorice on the surface of the compressor. When you see a lot of condensed water,frostorice on the surface of the compressor, it can basically be judged that the evaporator is blocked.
If the evaporator is blocked or the evaporator tubesarescaled,please disassemble the evaporator,and remove the evaporator tubes, then rinse with a high-pressure water gun or soake and wash with a special chemical liquid.