Cleaning AC Unit Saves Money and Increases Comfort and Lifespan of Unit

There are three places where dirt can cause your AC to work harder and fail to cool the house well

The Condensor - which is located outside.
The Evaporator - which is located inside.
The Filter - which is located inside, right before the evaporator in the air flow.

Dirty condensor coils prevent heat from being extracted from the hot, high pressure side.

The dirt clogging things up does not let any cooling air to pass through the coils, which are much hotter than the outside air. This means the unit must stay on longer and pump much more freon to remove the same amount of heat from the house. This problem gets much worse as the temperature outside goes up. The compressor is also located here. This type of condensor must be cleaned from the inside out which requires experience to avoid shocks or injury. The circuit breaker does not always shut off all power to unit and it contains capacitors with high voltage even after cutting the power. The fan can suddenly start causing serious injury. Please leave this part for the professional to clean.

BEFORE CLEANING

Photo of dirty condensor completely clogged with fine dirt.

AFTER CLEANING

Dirty evaporator coils fail to let enough hot house air to pass through cold coils.

The dirt clogging up these coils does not let the hot air in the house to pass freely. This means that most of the cold in the freon is wasted and returns to the compressor. This is one cause of units freezing up. The water that forms on the coils gets frozen when the air fails to warm up the freon in the tubes enough. The air that does pass through is cooled but there is very little of it to cool the house. So the unit stays on much longer, running up the electric bill and wearing out the compressor. Some evaporator designs are pretty much self cleaning as long as filters are used. Others clog badly.

Photo of dirty evaporator clogged with dirt.

Dirty filter causes same problem as dirty evaporator coils.

The filter is there to help keep dirt out of the evaporator, the blower blades and the ducts. Making the air cleaner for YOU is just an added bonus. A dirty filter also blocks air flow, running up electric bills, decreases comfort, can cause freezing of unit and wears out the blower fan prematurely. The evaporator gets dirty anyway since the filter cannot trap all of the dirt. But a good filter gives alot of extra time between cleanings.