Outdoor units may be cleaned with a hose and some detergent. Stay away from a pressure washer since high pressure might actually break sensitive parts and also inject water into sealed housings. Window units can be wiped down. Use a vacuum cleaner and a sweep attachment to very gently clean the aluminum fins associated with dust and debris. The fins bend very easily. Clean or replace the filter of the indoor unit before resorting it on. If a musty odor exists, a light spray with Lysol brand disi
