Mold in air conditioner

For the last couple days I’d been wondering why my allergies, normally relieved somewhat by being in an air-conditioned room, have been so terrible. Then last night I noticed that little spots of dark mold seem to be growing inside my air conditioner, right on the fan blades. I’m allergic to mold. Is there anything I can do to get rid of it? It’s a window unit but is very heavy and I can’t pull it out on my own. Is there maybe some kind of spray or something I could blast inside to kill it? Or am I just SOL?

Every window air conditioner comes with instructions on how to clean the filter. If you don’t have your instruction booklet, try looking up the model online. If the filter’s on the front of the unit, you shouldn’t have too much trouble accessing it. (I’ve had 2 units and the filters were in different places on each.)

Just spraying something inside won’t do much good. Mold will just come right back. Remember that mold grows where it’s warm, wet and there’s food. So you need to clean every spot you see, and re-clean every 2-3 months. One of the easiest cleaners is 2 parts warm water to 1 part white vinegar. Replace (or clean) the filter and clean the fan blades.

Be sure to unplug the unit before you go digging around inside and let all parts dry thoroughly before restarting. It’ll smell a little like a pickle for a couple of hours but you won’t be run out of the house by chlorine fumes, either.

But a one-shot spray that will kill mold and still be safe enough to use in a home? I’ve not heard of it. Good Luck.

“Tilex” for use in showers is 2.4% sodium hypochlorite. (Same thing as “Chlorox” but about 1/2 as concentrated) Labeled for removal of mildew. Follow directions on sprayer. Wipe off areas where you can. Rinse thoroughly and repeat next day if any signs of mold/mildew remain.
The mildew growing in fiberglas insulation can be killed by the spray, removal of insulation not a good idea. Caution: wear a mask or cloth over nose/mouth to avoid the spray.

I don’t think the filter is the problem here. It filters the air from the room passing over the evaporator coil to keep it from getting clogged up. Mold on the evaporator coil and fan blades is already downstream from the filter.

You say the unit is too heavy for you to remove by yourself. It is possible, even likely, that your unit is designed to slide out of the housing, which remains fixed in the window. If this is the case, you can slide the unit partially out to access the fan for cleaning. Be careful.

You could also try a good dousing with Lysol spray or similar. But while this will temporarily kill the mold and fungus, it won’t remove it. Only cleaning will do that.

Anyting containing chlorine is a very bad thing to do to aluminum parts, like the evaporator coil fins and fan blade. Since you can’t rinse it thoroughly afterwards, I’d not recommend this, even though it will kill the heck out of the mold and mildew.