When the weather outside is frightful, it may be a little late to have your heating and air conditioning system inspected. Even for folks in warmer climates, there's nothing that could ruin your holiday time faster than an air conditioner that breaks down on a sweltering Christmas Day dinner.

Inspecting this system (meaning spending a little money each year) can save you a bundle on the backside. A number of heating and air companies offer a biannual inspection program where a technician looks over your system for wear and tear, leaks, and impending breakdowns.

I've carried this type of protection for several properties and it's always been worth the investment. While many homeowners seek out ways to lower their monthly expenses, this is not one of those places. Think about it -- the furnace-a/c is used nearly every day of the year and in the winter time, it is an absolute necessity for those in colder climates. For many homeowners it accounts for up to half of all utility costs, so we know it eats up a lot of energy. If you have an exterior unit, it is abused by the elements and we hope it keeps working 24/7 despite all the abuse.

Several years ago, I had a unit break down in February. I had a very chilly family and a backup on the waiting list for a technician. I found out I wasn't the only one with heater problems on this cold weekend and techs make premium money off those who want the heater working now. Thus a regularly scheduled maintenance program is your best insurance policy.

A qualified technician should take a look at the following elements of your heating-a/c system:

• Check and adjust fan switch. If not operating properly a fan switch can waste energy and cause nuisance fan cycling.

• Check air filters. We know we're supposed to change these all the time, but when was your last filter change? Dirty air filters increase your system's operating costs and cause undo wear on the system.

• Inspect the heat exchangers. Heat exchangers crack and deteriorate with age. These cracks pose a risk of serious illness from the fumes.

• Clean the burners and check all components. Poor combustion is caused by dirty burners or defective components, wasting precious heat as it "goes up the stack."

• Clean/check ignition components. Failure of this one element of the system can cause ignition failure and shut the unit down.

• Inspect unit wiring. Loose connections and/or weak fuses lead to motor or control failure.

• Check safety controls. This is an obvious safeguard and if they are not operating properly, they can cause dangerous problems.

• Clean blower wheels and lubricate motors. This one item of the inspection alone will provide longer life for the motor and more consistent temperature control.

• Check fuel line/shut off valves. Undetected leaks waste energy and could become dangerous.

• Inspect flue pipes. This is another area where pipe corrosion or leaks can cause a very dangerous situation.

• Check/calibrate the thermostat. Defective or improperly calibrated thermostats increase operating costs while decreasing your comfort level.

For heat pumps, the technician will also check Freon levels and test for leaks in the system. If levels are low, this could be a sign of leaks in the system, which should be tested further. If none exist, then the system should be charged up with more Freon.

Maintenance, rather than emergency repair, is always the best move.

Published: December 24, 2004

Use of this article without permission is a violation of federal copyright laws.