Frigidaire markets wall- and window-mount air conditioners, as well as built-in and portable units, and all of them have filters that need regular cleaning. The filter is all that stands between the delicate machinery inside the unit and air that may contain dust, oil and grease from the kitchen, and other contaminants, such as pet hair. You can clean the filter with soap and water, but nothing stronger. If you can't remove all the dirt, you should replace the filter.
Location of the Filter
You can always locate the filter by checking the owner's manual for your model, but you probably won't need to do that. The filter compartment is almost always on the front of the unit behind a door with a prominent handle. On some portable units, the filter may be on the back, but the door and handle are still obvious. If you have a Frigidaire central air conditioning system, you'll find the filter compartment on the main air handler unit. You'll probably also find a filter behind the main air-return grille.
How to Clean the Filter
Turn off the air conditioner. Locate the filter compartment and open it. Grasp the filter by its tab and lift it out. It isn't attached with fasteners, so it should come right out.
Some portable units have three filters. Remove the top one by pulling out the panel, then grasping the tab and lifting it out. To access the other two filters, you must unscrew the lower intake grille and remove it. Remove one filter from the side panel and the other filter from behind the grille.
Vacuum excess dust from the filter. Use the upholstery attachment on your vacuum cleaner to avoid ripping the filter paper or otherwise damaging the filter.
Fill a bowl with warm water and add a few drops of dish-washing detergent. Use this solution to wipe down both sides of the filter, using a soft sponge or a microfiber cloth. When the filter is clean, replace the soapy water with clean water and wipe down the filter again to remove the excess detergent.
Let the filter dry thoroughly before replacing it. This may take a few hours.