Natural gas and propane burn cleaner than fuel oil, and most gas furnaces present fewer operational difficulties than oil burners do. In fact, the problems that affect gas furnaces typically involve the furnace’s thermocouple, the pilot light, or some component of the electrical system.
Gas furnaces and heaters have control shutoffs to prevent gas leaks, but they are not fail-safe. If you smell gas in your house, do not turn any lights on or off, and do not try to shut off the gas leading to the furnace. Get out of the house, leaving the door open, and immediately call the gas company or the fire department to report a leak. Do not re-enter your home.
 © 2006 Publications International, Ltd. Most natural gas furnaces have few operational difficulties. Problems typically involve the pilot light, the thermocouple, or some part of the electrical system. |
On some gas furnaces and heaters, a plug-type door covers the pilot light assembly. To gain access to the pilot burner, pull the door out of the furnace housing. On other units, remove the panel that covers the pilot and gas burners.
The pilot light controls, reset buttons, gas valves, and thermocouple are usually contained in an assembly at the front of the furnace. The furnace limit switch is located on the plenum (main chamber) or main duct junction on the upper housing of the furnace.
Now that you’re ready to fix your furnace, save some time by identifying exactly what’s wrong with it. Look for your problem, and solution, on the handy chart on the next page.
For more articles on home repair, check out the following links.
- Furnace Maintenance: Save yourself time and money by learning the steps to keep your furnace in prime condition.
- Major Appliance Repair: If the furnace isn’t the only thing in your house on the fritz, you can learn how to fix other machines in this article.
- Small Appliance Repair: Once you’ve tackled the furnace, a toaster or blender seems like child’s play. Find out how to fix them here.
- Thermostat Maintenance: To make sure there’s actually a problem with your heating system, you may want to check the thermostat, too. Learn how to calibrate a thermostat.
