To clean the exterior of a PTAC or packaged terminal air conditioner, wipe down the cover with a damp sponge and an all-purpose cleaner or mild detergent to remove smudges, dirt and lint. Remove dried material and loose debris with a soft bristle brush or vacuum cleaner hose.
Once the cover is cleaned, the device can be removed so the coils can be washed from the inside out.
The condenser coils within a PTAC should be pretreated with coil-cleaning solution and rinsed with a low-pressure washer. High-pressure washers can damage the fins within the unit. The indoor coil can be sprayed down with a low-pressure washer, and the base pan can be cleaned by removing debris and wiping drain passages with a damp cloth.
Air vent filters should be cleaned once each month in addition to rinsing off filters. Filters that are torn or damaged with holes should be replaced with a fresh, new one. The fan motor oil may need to be oiled when cleaning the unit. The front cover and grille should be properly mounted when reassembling the unit.
PTAC units should be cleaned annually in most residences. If the unit resides near recent construction or is exposed to pet hair, cleaning more often may be necessary.