Best Practices for Furnace & Air Conditioners

Maintaining Your Air Conditioner

An air conditioner's filters, coils, and fins require regular maintenance for the unit to function effectively and

efficiently throughout it's years of service. Neglecting necessary maintenance ensures a steady decline in air conditioning perfomance while energy use steadily increases.

Air Conditioner Filters

​The most important maintenance task that will ensure the efficiency of your air conditioner is to routinely replace or clean its filters. Clogged, dirty filters block normal air flow and reduce a system's efficiency significantly, with normal air flow obstructed, air that bypasses the filter may carry dirt directly into the evaporator coil and impair the coil's heat-absorbing capacity. Keeping the filter clean can lower your air conditioner's energy consumption by 5%-15%.

For central air conditioners, filters are generally located somewhere along the return duct's length. Common filter locations are in furnaces or in the air conditioner itself.

Some types of filter are reusable, others must be replaced. They are available in a variety of types and efficencies. Clean or replace your air conditioning system's filter or filters every month or two during the cooling season. Filters may need more frequent attention if the air conditioner is in constant use, is subjected to dusty conditions, or you have fur-bearing pets in the house.

Air Conditioner Coils

The air conditioner's condenser coil collect dirt over their months and years of service. A clean filter prevents the coil from soiling quickly. In time, however, the coil will still collect dirt. This dire reduces air flow and insulates the coil, reducing its ability to dissipate heat. To avoid this problem, check your coil every year and clean it as necessary.

Outdoor condenser coils can also become very dirty if the outdoor environment is dusty or if there is foliage nearby. You can easily see the condenser coil and notice if dirt is collecting on its fins.

You should minimize dirt and debris near the condenser unit. Your dryer vents, falling leaves, and lawn mower are all potential sources of dirt and debris.

Cleaning the area around the coil, removing any debris, and trimming foliage back at least 2 feet (0.6 meters) allow for adequate air flow around the condenser.

Coil Fins

The aluminum fins on evaporator and condenser coils are easily bent and can block air flow through the coil.

Condensate Drains

Occasionally pass a stiff wire through the unit's drain channels. Clogged drain channels prevent a unit from reducing humidity, and the resulting excess moisture may discolor walls or carpet.

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Maintaining Your Furnace

The following maintenance should be provided by a heating system professional.

All Systems:

Check the condition of your vent connection pipe and chimney. Parts of the venting system may have deteriorated over time. Chimney problems can be expensive to repair, and may help justify installing new heating equipment that won't use the existing chimney.

Check the physical integrity of the heat exchanger. Leaky boiler heat exchangers leak water and are easy to spot. Furnace heat exchangers mix combustion gases with house air when they leak--an important safety reason to have them inspected.

Adjust the controls on the boiler or furnace to provide optimum water and air temperature settings for both efficiency and comfort. if you're considering replacing or retro fitting your existing heating system, have the technician perform a combustion-heat test.

Forced-air Systems

Check the combustion chamber for cracks

Test for carbon monoxide (CO) and remedy if found

Adjust blower control and supply-air temperature

Clean and oil the blower