Dispensing head if the distribution is uneven, will make some subway refrigerant too much, so that the evaporator frost results in incomplete evaporation, affecting the system refrigeration capacity decline, but also may cause suction with liquid.
1, from the point of view of how much shunt flow.
(1) If the diversion liquid amount is on the high side.
Coil outlet superheat is very small, and even with the unevaporated liquid, the heat transfer area is less than 1 At the same time, the evaporator outlet manifold due to refrigerant mixing or evaporation, superheat is lower than the theoretical | value, superheat decreases, the signal generated by the throttle device is too much liquid supply, the throttle device adjusts itself to reduce the amount of liquid supply;.
(2) If the amount of liquid diverted is low.
Mass flow rate is reduced, the effect of liquid separation is even worse, forming a vicious circle; ultimately leading to a sharp reduction in the effective area of the evaporator, the cooling capacity drop, the whole refrigeration system performance deterioration.
2、From the working mode of refrigeration system.
(1) When the unit is heating
Uneven distribution of liquid will cause incomplete evaporation of refrigerant in the circuit with more liquid distribution, which will lead to rapid frost formation in this circuit. If the frosting is very serious, it will cause the frosting to be not clean, and then the vicious circle, the compressor will return to the liquid, and the low pressure will jump to a stop.
(2) When the unit is cooling
When refrigerant evaporation is incomplete in the circuit with a lot of liquid separation, the temperature of the coil is low and the dehumidifying capacity is strong, and if it is serious, the indoor coil will be frosted and the compressor will return liquid.
Post time: Jan-08-2024