Maintenance key to efficiency of furnace

October 14, 2007

My furnace is about eight years old and I know there are more efficient ones on the market. Would I be smart to change it out for a newer one?

When it comes to whole heating systems, we like to say, “If it ain’t broke, don’t fix it.” New heating systems are more efficient, but they’re also a big investment so the financial payback can be lengthy. So it’s probably smarter financially to delay your purchase and maintain the existing system at peak efficiency. An exception to this would be if you are routinely spending money repairing the furnace. Also consider how long you plan to live in your home, and whether a major remodel is in the future.

If you keep your existing system, there are simple steps to take to reduce energy use.

For starters, have the furnace cleaned and tuned up to make sure it’s operating at peak performance. And have the technician check the thermostat. Clean furnace filters monthly during the heating season and be sure that furnace ducts are clean and vents are not blocked by furniture or drapes. Check the air flow from each vent. If you have little or no air flow, a duct could be disconnected or blocked and should be corrected.

Smart use of thermostats

Turning down the thermostat is a simple way to save energy. You’ll save 1 percent to 2 percent on heating costs for every degree the thermostat is lowered for an eight-hour period. We recommend a daytime setting of 68 degrees, or the lowest comfortable setting. We suggest setting the thermostat back 10 degrees at night, unless you have a heat pump, in which case we strongly recommend a programmable thermostat and suggest a nighttime setback of 6 to 8 degrees. You can also use a programmable thermostat with other types of heating systems.

Weatherize the home

The furnace will work more efficiently — and your home will be less drafty — if you stop air leaks that let heat out and cold air in. It doesn’t take much of a gap to cause significant heat loss and drafts. A one-quarter-inch gap along a stan- dard door has about the same effect as a 4-by-5-inch hole in your wall. Air leaks typically occur around doors, windows, plumbing and electrical openings, electrical service panels and attic hatches.

Weatherstripping, foam and other sealants are inexpensive and an easy way to seal air leaks. Home improvement and hardware stores can help you determine the right product.

After any home-sealing project, it’s recommended to have a specialist check to make sure gas-fired appliances (furnaces, water heaters and clothes dryers) are venting properly.

Ductwork can be another energy waster. The Environmental Protection Agency reports a typical home loses 20 percent of the air moving through ductwork because of leaks or poor connections. Leaky ductwork also means less heat is delivered, so your furnace must run longer.

If you choose to do the project yourself, use mastic sealant or metal tape to seal ductwork you can access. Duct tape, while a terrific solution for other applications, ironically is not recommended because it is not long-lasting. It doesn’t meet local building codes, either. Pay special attention to the connections at vents and registers, which are common places to find problems.

Finally, adding insulation will help your home retain heat better. However, how much to add to your attic or crawl space will depend on how much is already there and how the house is constructed. There is more information on insulation on our Web site at clarkpublicutilities.com.

Whether you opt for a new furnace or stick with the older model, these simple changes can increase the home’s overall efficiency, and possibly extend the life of your heating system — new or old.