Article: Servicing the a/c while it's connected to power may result in electrocution. If it feels hot, the unit's coils are most likely dirty and need to be washed.      Some air conditioner units require the motor be lubricated. Do this now while your unit is open. The air conditioner filter should also be replaced every few months. It is usually located near the return air duct by the furnace.

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Make sure the unit is turned off either at the on/off switch and unplugging it or by shutting off the circuit breaker. Check the small copper pipe connecting the unit to the house. Rake any leaves and debris away from the unit before you start to service an air conditioner. Take the cover off the unit, and locate the air conditioner coils (they look like a car radiator). Use a soft brush to brush any dirt and debris off the outside cover. Cover the motor and wiring with a plastic sheet. Hose down the fins, coils and inside of the unit. Check your owner's manual. Replace the unit cover, and turn it on to make sure it runs properly.