Dirt is the biggest enemy of any furnace. It wastes fuel and drastically lowers the energy efficiency of both electric and gas furnaces. Three parts of your furnace should be cleaned every year – the air filter, blower and motor. If you are feeling handy, you can try to take care of your furnace air filter first.
The filter system should be replaced or cleaned at the beginning of the heating season and once a month during the winter and other periods of continuous use. Before you begin the project, make sure the furnace is shut off. Check your furnace air filter by taking it out and holding it up to the light. If you can see any clogs on the filter, it is time to get a new one.
Most disposable filters are made from fiber mesh in a cardboard frame. When replacing one of these filters, look for the arrow on the frame which shows the direction of air flow. The arrow should always point away from the return-air duct and toward the blower. If you have a permanent filter, it is usually sprayed with coating chemicals. Clean the filter according to the manufacturer’s guidelines which are usually attached to the furnace housing.