Your Air Conditioning

By: Yale Wolk, Erinson Home Inspections

Central air conditioning is now a standard feature in homes. The term “central” means that there is one system which serves the entire house. Central air conditioners consist of two parts. The first is inside. It houses an evaporator coil and a fan (blower). This unit is often referred to as an air handler. It is connected to ductwork which distributes the cooled air throughout the house. If you have a furnace for heating, the evaporator coil will usually be mounted on top of it so that the furnace’s fan can also serve the air conditioning. There will be a small pipe at the bottom of the air conditioning unit. This is for condensation which precipitates as the air conditioner cools the air. Moisture collects in a pan below the evaporator coil, flows into the condensate pipe, and then flows out of the house.

The second unit is typically located outside the house in the yard. This unit is referred to as the compressor. There is a large fan inside, with slots or openings in the frame. Inside there is also a sealed compressor, which manipulates a refigerant, which many people call Freon (actually DuPont’s trade name for the product) to produce the cooling effect. The refrigerant is transported from the exterior compressor-condenser unit to the evaporator coil inside the house via a thin, bare copper tube. It flows through a series of tubes built into the coil, absorbing heat from the house. The heated refrigerant is then conveyed back outside via a second, larger copper tube wrapped in insulation, where the heat is then released into the air. This process cools the house. And it pulls moisture from the air as condensation. This is critical because if the moisture content remains high, you could feel as though you’re living in a cold wet cave.

Maintenance Procedures

Most maintenance tasks should be left to a qualified heating/air conditioning contractor or service. The unit should be serviced every other year, at which time the technician will check all operating components, including the refrigerant levels in the compressor-condenser. In addition to this professional servicing, though, your primary reponsibility is to change or clean the filter. Every 30 days, install a new filter (if you’re using disposable filters) or wash your filter if you have the reusable type. Don’t run your system with a dirty filter. Dirty filters allow dirt and dust to accumulate on the bottom of the air exhanger, restricting air flow, and forcing the unit to struggle to maintain a sufficient air flow. This can damage the system.

Periodically check to insure that the condensate line is working. Is water actually coming out of it while the air conditioning is operating? From time to time, the condensate line can get clogged with a piece of dirt, lint or rust. If this should happen, the condensate will continue to build in the pan and then will overflow. It can get into the internal components and cause rust. Observe the condensate pipe when the unit is running and see if water is coming out. If not, call your air conditioning service for a cleaning.

Also check periodically to insure that your outside unit-the compressor-condenser- is level. There are critical fluids and gases circulating inside the unit, adn it must be level to operate properly. In many houses, especially new homes, there can be settlement within the first 4 to 6 feet from the foundation wall. This can cause the compressor to tilt at an awkward angle, and a severe tilt can cause serious damage inside. If you see your compressor/condenser begin to tilt, you can shim it to re-level it.