How can I clean the coils in my window a/c unit?

Question

My window unit A/C has been freezing up from time to time. I keep the filter clean, but I am wondering if cleaning the coils behind the filter would help.

Thanks!

Answer 1

HVAC Tech.:you need to remove the front cover and the filter. That will expose the coil fins. You can mix water and vinegar (50/50) in a pistol pump sprayer and take your time the vinegar will clean and remove the slime, use the hard spray and spray in  to clean deep into the coil, and clean the drain at the same time. wash the filter before you put it back together.

Answer 2

It would to be pretty plugged to cause the freezing.

1. Remove the window unit from the housing.

2. Remove the top cover over the evaporator coil.

    Depending on your model you may have to cut the                styrofoam and replace later.

3. If posible remove or cover electrical and motor.

4. Use a degreaser and water to clean.

But more likely than not you may be low on refrigerant.  It may be cheaper to just buy a new one.

Answer 3

You can attempt to blow the buildup off the coils with an air gun/compressor if you have one.  If you don't you may want to try a feather duster (cheap) or if it can reach, a venetian blind vane cleaner.  

The cleaner the inside of the unit, the better.  But it may not be the cause of your freezing up.  When coolant is under pressure it gets cold.  The cold is transferred over the vaned portion of your AC, and in the case of a window unit, that is separate but attached to your coils.  If you have any kind of blockage that prevents the coolant from circulating, you will get freezing.  Even a partial blockage.

If it is an expensive or fairly new window unit I would try to get the entire interior as clean as possible--the case comes off--but if it is older and or a cheaper unit, and it keeps doing it, I would just bag it and spend the hundred or so for a new one.  Taking it in for non warranty repairs will cost you almost as much as you will pay for a new one these days.

Answer 4

We always take ours out of the window and down to the car wash

Answer 5

you said that it is freezing up once in awhile try turning down the thermostat just a little bit sometimes if the unit is set at the highest setting it will get so cold that the condensation will freeze on the evaporator it could be just that simple