Is there more than 1 HVAC filter?

Question

Last night, the line to my condenser outside became all ice. My air conditioner does not blow cold air. I called a technician who said to check the filter.

This is a stupid question, but did he simply mean the big rectangular intake filter that is in my wall? Or is there a filter in the furnace or condenser outside that I need to check? (perhaps the fins?)

BTW, I have a heat pump type of unit.

Answer 1

HVAC Tech.:  The only filter he would have ment for you to check would be the return air filter. I hope he told you to shut the system Down for a few hours. Any time there is ice At the compressor SHUT IT DOWN you are about to have major repair bills.    The reason he said to check that filter is the problem could be blocked air floe. If you have run the unit without that filter maybe enough dirt, hair, and other nasties have blocked the evaporator coil and air cannot get through it.  It would have to be cleaned. only two other causes, one is overcharge in the system the other a crimp or sever bend in that iced line. Get a technician to check it out before the damage becomes super severe.

Answer 2

He is talking about the filter in your furnace.  The condensor works in combination with the evaporator coil, which is located near the furnace.  If the filter in the furnace is clogged, it restricts the air flow across the evaporator coil.  If the air flow is restricted across the coil, the cold created by the condensor is not transferred to the air that is circulated through the ductwork.  The freon then returns to the condensor at the colder temperature, only to be cooled even further by the condensor.  Eventually, the unit will freeze up.