Most residential central air conditioning systems are “split systems” that have the compressor and condenser coil housed in an outdoor unit which is connected to an evaporator coil inside the home by the coolant lines. Most heat pumps have a similar set up.
A heat pump or central air conditioning system should be professionally serviced in the spring and fall by an experienced HVAC technician. Most homeowners don’t have the tools and equipment necessary to perform a full service on a central air conditioning system. Accordingly, most homeowners should call a professional for air conditioning service and repair.
However, between service calls a homeowner can help keep the system operating efficiently by regularly changing the air filter and by keeping the condenser and evaporator coils clean. The evaporator coil is located in the ductwork (called the plenum chamber) above the furnace. If you have a heat pump, the evaporator coil is located in the air handler downstream of the air filter.
If you religiously change your furnace filter (or air filter) and never use anything other than a pleated filter, your evaporator coil will stay clean and free of dust, lint, and other debris. Unfortunately, most homeowners are a little lax in their furnace filter habits and the evaporator needs to be cleaned occasionally.
In some units, the evaporator cannot be accessed by a homeowner. In others, you can reach the evaporator through an access panel on the front of the unit. If your evaporator is easily accessible, clean it carefully with a brush or a vacuum cleaner with a brush attachment. Remember to turn the power to the unit off before starting and be very careful not to bend any of the soft aluminum fins.
Once your evaporator coil is clean, you can avoid future cleanings by using a high quality pleated air filter and changing it regularly. Your HVAC technician can help select the right air filter for your system.
