I found this on the internet....pretty much the last paragraph was about cleaning, but thought the whole thing was good.
Window air conditioners are usually plugged in and forgotten – until they stop cooling properly, or until they exhibit problems. Don’t just plug in your window air conditioner and ignore it. There are things you must do to properly maintain your window air conditioning unit in an effort to avoid problems. Taking proper care of your window air conditioner will ensure the unit will continue to provide the cold air you want when you need it the most. Don’t wait for problems to start before taking the necessary steps to keep your window air conditioner running properly.
The following information provides facts and tips on what you must do to avoid problems with your window air conditioner. Also included are troubleshooting tips for correcting common problems with window air conditioning units.
Any item that uses an air filter can’t run properly if the filter is dirty, and window air conditioners are no exception. If you want your window air conditioning unit to run properly and efficiently, it’s imperative that you change or clean the filter once a month.
The filter isn’t the only part of a window air conditioner that requires regular care and cleaning. The condenser coils can become covered in dirt and dust, and they should be cleaned at least once a year. Even if condenser coils don’t appear to be dirty, grime and dust can hide in places not readily visible.
While the air conditioner is unplugged and the condenser coils are dry, vacuum the coils with a crevice tool, blow away dirt and dust with an air compressor, or clean the coils with a soft brush such as an old toothbrush. This is an easy preventative measure that you can do yourself in an effort to avoid problems while lowering your electric bill in the process.