Question

(True or False) After diagnostic of an evaporator coil found covered with 1/2 of the coil of low & insufficient refrigerant levels?

Answer 1

it may be true.because

1. if the total refrigerant charge is low but not exhausted, then insufficient refrigerant is avaliable on the liquid side of the refrigerant metering device to adequately feed the evaporator coil with liquid refrigerant. In that condition the vaporization temperature of the refrigerant inside the evaporator coil is around the same as the freezing temperature of water - which makes condensate freeze on the coil surface.
2. If on the other hand there were adequate refrigerant, then there is more liquid refrigerant inside the evaporator coil and heat is being removed (the coil is being cooled and heat in air blowing across the coil transfers into the coil) at a higher temperature - above the freezing point of water.
3. if we've got the right amount of refrigerant in the system is to see where the frost line is on the system. If the frost line stops in the top third of the coil then we don't have enough refrigerant - we are running out of liquid refrigerant inside the coil too far from the end of the coil.