Ask the Inspector: Furnace checkups

How often should I have my furnace checked?

I recommend getting your heating equipment checked annually.

Heating specialists recommend new gas furnaces be checked every couple of years, until they are five years old. At that time, yearly servicing is recommended.

If you have an oil furnace, their nozzles and oil filters need to be changed every year. Prolonging that will greatly decrease the efficiency of your furnace.

In a forced air furnace, a filter protects the blower and motor from damage due to dust and dirt intake. A regular furnace filter should be changed every month during the heating season. During the cooling season, it's best to check monthly and replace it if it becomes dirty.

I have seen some filters so dirty that I was surprised the furnaces could even run.

Some specialty filters do not need to be changed as often, but check with a heating specialist before you use these filters. Some of the specialty filters are so dense they can restrict the air flow of the furnace and make it work harder to do its job.

Running your furnace without a filter or a dirty filter can do serious damage to some of the components, especially the heat exchanger, which is the most important part of a furnace.

If you have a new high efficiency furnace installed and it no longer needs to go to the chimney and has PVC chimneys that go out the sidewall and the gas water heater is left in the chimney by itself a chimney liner for the water heater must be installed. Without the furnace in the chimney anymore it doesn't draft as well.

If you see you have thermal vent dampers in the furnace chimney and water heater chimney they should be removed. You can easily identify them. It says thermal vent damper right on them. They are known for sticking shut and kicking carbon monoxide into the house. I had one last week that was kicking over 200 parts per million of carbon monoxide for about 30 seconds until it finally opened up. This is an easy repair; the thermal vent damper is removed and the vent pipe is extended to take the place of where the thermal vent damper was.

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Ask the Inspector: Furnace checkups