What Are the Causes of Excessive Fuel Consumption in Gas Furnaces?

Drafts

• The U.S. Department of Energy claims that gas-based furnace systems only use roughly 90 percent of the heat that results from burning the gas. The other 10 percent escapes through openings such as the chimney – even if the chimney is never used – or through other openings such as improperly closed windows, attic spaces and in areas that aren’t properly insulated. Address these problem areas to up your furnace's fuel efficiency to closer to the 100 percent mark, thus reduce your monthly heating bill by reducing gas usage.

Furnace Type

• Furnaces are either electrically controlled or use a pilot light. Each method directly affects how well your home consumes gas and, in turn, generates heat. A regularly burning pilot light, a typical feature in many older homes, uses only 68 to 72 percent of the expended energy to heat the home. The rest, the remaining 28 to 32 percent, is lost due to the pilot light itself. The Department of Energy advises homeowners to consider swapping their pilot light furnaces for more energy efficient electrical furnaces or heat pumps. The initial expense pays off in the long run by reducing overall consumption.

Insulation

• Heat is lost not only through drafts and open spaces such as window cracks and crevices and openings around doorways, but also through the walls, ceiling and floors – a direct loss because of poor or lacking insulation. Luckily, spreading rolls of insulation over crawlspaces and across attic floors is an easy task. In the case of insulating walls, you or a contractor can use spray-on insulating foam to fill wall spaces and effectively reduce heat loss.

Home Construction

• The very construction of your home, not just insulation issues, may be to blame. Older homes are notorious for gaps and seams created as a result of years of settling. These small gaps in the brick or mortar work of the home can be closed off by replacing the existing exterior with vinyl siding. This type of siding doesn’t age the same way as brick and mortar and acts in small way like an oven by trapping heat inside the home.