Determination of the cause of frost in finned evaporator for refrigeratorView: 11407/27/2021
1, from the compressor return port gradually to the direction of finned evaporator for refrigerator frost causes.
(1) the throttle valve open too much, the appearance of condensate return temperature and pressure is normal or slightly high, from the compressor return port gradually to the direction of finned evaporator frost.
(2) Finned evaporator can not absorb heat normally, or the cold volume generated by the Finned evaporator can not be taken away. The appearance of the return liquid temperature and pressure is normal or slightly low, from the compressor back to the direction of finned evaporator frost gradually, after a long time from the compressor back to finned evaporator and throttle valve to the evaporator section all icing, and finally appear low pressure.
Check methods are.
1. to see if the air filter is clean.
2. to see if the fan speed is normal.
3. whether the finned evaporator is clean.
4. whether the air supply system is clogged.
5. whether the belt is too loose
2. Possible reasons for frosting from the expansion valve to the direction of finned evaporator
(1) The refrigerant is low (leakage), the appearance of the condenser back to the liquid temperature is high but the pressure is not high, from the throttle valve to the direction of finned evaporator frost gradually.
(2) The expansion valve is opened too small, the appearance is that the condenser return liquid temperature and pressure are normal or slightly low, and the frost is gradually formed in the direction of finned evaporator from the throttle valve.
(3) Check the sight glass to see the refrigerant situation, if the bubble is serious, it may be the system leakage; if the refrigerant in the sight glass is not bubbling or rarely bubbling, it may be the expansion valve is opened too small or blocked, generally there will be a large temperature difference before and after the blockage.
Of course, in addition to looking at the direction of frost, if the surface of finned evaporator for refrigerator are frosted, it is necessary to do a more detailed analysis ......