Both the evaporator and condenser coils (inside and outside) can be safely cleaned with products specifically made for the job. Clean evaporator and condenser coils mean more efficient cooling - which
means lower operating costs. Cleaning the coils can remove stale or
other less desirable odors that originate from your air conditioner. An example is made by Thermwell
which is available at Lowes and other hardware and home improvement stores. There are many different manufacturers of the cleaners - so if this particular brand isn't available at the store you shop, another will do. Different brands and types have different methods - so you should read and follow the directions on the can. Many of the canned foaming / spray type cleaners are "rinse free" - meaning it is not required to rinse the foam off - as running the unit will allow the condensation that forms of the coils to do the rinsing for you. It should be noted that window / thru the wall types and other non-central air conditioning units should be tilted so that the condensation and chemicals drain outside - not into the house. If your AC hasn't been dripping water inside, it should be fine. Usually all that is needed is to remove the front grill and filter to access the coil. With the unit off (preferably unplugged) spray the foaming cleaner into the coil and let it sit to work on the dirt, grime, mold, nicotine, etc. that has collected on the coil. When the last step of the can's printed directions are complete - the job is done. You can find some helpful videos on Youtube
to show how the cleaning is done on the larger, central air type units.
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