panel (it might be screwed on with hex bolts) and take it off. If you see ice built up inside, then you have to let that melt. The quickest way to do that is to run the unit with only the fan on (no cooling at all). When all the ice is gone, then you can run the air conditioner again.

Also, many times the reason the a/c unit ices up is that the filter is dirty. Be sure you have a clean air filter in there before you try to run the cooler again.

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