frosted evaporator coils

MissTFried

The evaporator coils in my air handler have frosted up for the 3rd time in 4 days. I assumed that the likely cause was was lake of air flow over the coils. I have cleaned them thoroughly assuming that since they had not been cleaned in at least 5 years it might be time to do so. I am satisfied that the cleaning job is as good as it can be without taking the coils out of the unit. I can see light being transimtted from the top side through the bottom. (I could not see any light before cleaning).

The only other thing that I suspect is that the system might be low on e refrigerant.

Anyway does any one have any other ideas what the cause of the frost can be.

carmon

That may be a good assumption...it is a likely cause

joecaption

Dirty filters is about the only other cause.

biggles

if the coils were packed then you need to look at the fins rounds on that swuirrel cage for the supply fan.once the filter gets packed..then the aquirrel ctches it then up to the A coil..to clean you have to slide the fan housing out remove the motor then lift the squirrel cage out.should go back in as removed.motor is likely inside that squirrel can't re-install backwards...hope that is it.charge might need adjusting,after all is lean if you notice ice as the night cools from a hot day that is a sign as the pressures change when the outside cools off from a real hot day.ice starts always on the insulated suction line at the air handler..quick test if you see some ice walking out on it...go outside and take a garbage can cover and put it on top of the running condenser slightly off center..get somebody inside to yell out to see if the ice melts away after 5 minutes retricting the discharge air.....that is a charge situation....