Central Air Conditioner Ice
What would cause ac to have ice on it?

Why Does Central Air Conditioner Ice Up?

Link below are common central air conditioner icing problems we received from visitors to central air conditioner and refrigeration cycle. Com.

We provide the ability to discuss your icing problem below. You will need to scroll down and search the link for the information you need to read or discuss.

What will you find in these lists of air conditioner problems?

Ice                   or                   Frost

The icing problem within central air conditioning unit comes into difference categories.

Air flow, refrigerant, metering device and other problem

Here are the reasons and explanation to why central air conditioner builds ice.

Air Flow Problems

Dirty filters

Yes, dirty filter does cause indoor coil to ice up. Why? The indoor coil is about 40°F. Dirty filter prevents the air from flowing through the indoor coil and cause it to freezes up.

Dirty evaporator coil

Dirty evaporator coil have the same reaction as the dirty filter, so read above.

Indoor blower not working

If you were to turn the Fan from Auto to ON, that is the indoor blower air coming from the supply vent. The indoor blower supposed to move the cold air surrounding the evaporator coil.

If the blower doesn’t work, the cold air just stays there. It does not move.

Refrigerant Problem

Not enough refrigerant

Lack of refrigerant inside central air conditioner cause the evaporator coil (indoor coil) to freezes up.

Perfect or Fine Leaks

Small leaks within the evaporator coil can cause the evaporator coil to build ice around it.

Outdoor temperature is too low

Running central air conditioner on low outdoor temperature can cause indoor coil to build frost.

Metering Device

Malfunction expansion valve

Metering device that is not providing the correct amount of refrigerant to the evaporator coil can cause the coil to ice up.

Other Reason Why Central Air Conditioner Ice Up

Low pressure switch fail

This switch prevents air conditioner operates on low pressure. Low pressure and temperature will cause the evaporator coil to ice up. No all central air conditioner have this low pressure switch.

Oversize central air conditioner

This is not likely going to occur! It could happen. It’s just too silly to explain it.

Restriction within the copper pipe

Restriction can occurs near the indoor coil or anywhere in the copper pipe and cause that specific area to have ice or frost.

The cost of having ice in the indoor coil

Central air conditioner ice up is a serious problem and most people do not see it that way.

Ice in the indoor coil means there will be liquid Freon entering the Ac compressor.

Why don’t we want liquid Freon to enter the compressor?

Ac compressor can’t handle liquid Freon. It will damage the compressor. That is why we need the indoor coil to turn all liquid Freon to gas.

If the evaporator coil has block of ice, it prevents the heat transfer to occur within the evaporator.

The block of ice is kind up blocking the airflow through the evaporator coil.

The cold Freon within the evaporator coil supposed to absorb the heat and turn to gas. It can’t do that if there is block of ice on the evaporator coil.

Central Air Conditioner Ice Up
Discussion Location

Where does the air conditioner ice up occur? Make sure to provide detail and description.

Is this Heat Pump, regular air conditioner, window unit or portable ac?

What Other Visitors Have Said

Click below to read air conditioner icing discussion from other visitors...

The Evaporator Coil Is Cover In Ice 
The radiator inside the home behind the air filter gets cover in ice, is this normal? It is causing the filter to get wet and start to rot. there is …

Regular Central Air Conditioner Icing Up. 
About a week and a half ago, we noticed that our central air conditioner did not seem to be working properly. We went outside to look at the unit …

Outside Unit Has Ice 
My Carrier central ac is not reaching the temp set on the thermostat. Cool air is blowing all the time. There is ice on the unit outside see picture. …

Ice on low pressure liquid line. Not rated yet
As soon as the central ac unit turns on it starts to build up frost that turns into ice later on the small low pressure liquid lines that spider out of …

Click here to write your own.

Return to central air conditioner and refrigeration cycle from central air conditioner ice