Top 7 Causes of Frozen Evaporator Coil

  Top 7 Causes of Frozen Evaporator Coil

Hello Everyone. Welcome to our site “qualitytipz”. Today we are going to check the causes of Ice Formation on Air Conditioner Evaporator Coil or Indoor Coil. So, let’s start. 

Why an Evaporator Coil Freezes?

The first thing to realize while fixing a frozen Indoor coil is that the coil is meant to be cold but not to be freeze.

 In a good running AC unit, the evaporator coil circulates the refrigerant at the appropriate temperature to remove heat from the airflow (Return Air) passing through the coil and not more to produce ice on the coil. 

The evaporator coil on my air conditioning system had frozen and seems pretty bad so I turned off the AC system and I just ran the unit on Fan mode and after about an hour the coil is completely free from Ice. This same condition may happen in your ac that’s why you are here. Just joking..

If we didn’t noticed the ice on the coil, the blower continues to run without air circulation causing over stress to the compressor. It makes compressor overheating and trips the unit.

What are the Common causes of this problem?.

There are many reasons why an Air Conditioning system will freeze over like this in my particular case, 

1. Dirty air filter

If an air filter gets more dirty, it reduces the air flow from the room to circulates over the coil and you feel hot. As speaking technically, the low temperature and low pressure gas inside the evaporator coil can’t absorbs heat and when the refrigeration cycle continues to run causes ice over the Indoor coil.

2. Blocked Air Ducts

In ducted air conditioning system, if we closed the return air registers the same ice issue will occurs on the evaporator coil. 

3. Dirty Evaporator Coil

If there is no air filter, the dust directly deposits over the coil and time being it closes the air flow and causes gas to freeze over the coil. So, while the filter don’t damage it.

4. Coil and Room temperature sensors

The coil sensor and room temperature sensors monitor the temperature and maintain the cooling inside the room. When it fails, the compressor runs continuously and causes ice on the indoor coil.

5. Contactor and Relay

The damaged relay and indoor relay acts like a switch to start and stops the contactor. When it fails to stop, the compressor runs directly and causes ice on the evaporator coil.

6. Indoor blower

When indoor blower fins are damaged or blower running in slow speed due to weak capacitor, evaporator coil will starts freezing.

7. Low Refrigerant

Refrigerant line is a closed loop system. When the refrigerant level is low due to leakage, there will be ice on indoor coil and on the copper coils. Also, if any pinch in the suction pipe during installation or damage by someone gas flow restricts and causes ice.

Tips to do to avoid frozen AC Coil.

1. Clean the Indoor filter twice in a month. This is not a tough job. Check DIY videos on Youtube and try it!!

2. Before Summer call Professional AC tech jinicians and clean the AC Indoor and Outdoor completely and do maintenance like checking gas levels, checking Indoor and Outdoor coil for any leak or damage, inspect any noisy from blower.

Thanks for reading and please leave a comment if any doubt’s

Okay friends, See you in another interesting topic.

Have a great day, Bye.

Author

Engr. Ahmed Hussain