Should your furnace ever shut down, your first response would usually be to call in an HVAC professional to get it going again. It’s a good idea to do this if you can. During storms or frigid spells, though, HVAC crews are usually overworked, and could take time getting to your home. If possible, you should attempt to restart your furnace all by yourself. While you should certainly wait for a visit by a professional if you have no idea what you’re doing, most people could get through the process with only minimal guidance.
Check everything else first
Furnaces can go out for all kinds of reasons, and it’s a good idea to eliminate each one before you look at the furnace itself. If you’re up to a little DIY work, you should also check the thermostat itself. You need to open the front cover, and check the moving parts inside to make sure that the contacts are clean and in good shape. If they seem dirty, you can clean them with nothing more than a piece of cardboard. It isn’t a good idea to use tools like nail files.
You should also check the emergency switch for your home. If a circuit breaker has tripped, you should call in an electrician.
Getting to the furnace
Once it’s clear that you need to turn your attention to the furnace itself, you want to first check to see that it has enough fuel. If it does, press the safety relay button, and then the burner restart button. Pressing both once each should do the trick. If it doesn’t, you need to call in the professionals.
If you have a gas furnace, an extinguished pilot lamp could be your problem. The pilot lamp is a little flame that gets the main furnace fired up. If it’s out, it disables the self-starter mechanism.
On most furnaces, the procedure is to first turn down the thermostat all the way, turn off power to the furnace, turn off the gas supply, and then take a match to the pilot. Once it’s done, you only need to turn the power and gas supply back on, hold down the reset button for a half minute, and then turn the thermostat back up.
Learning the simple steps to restarting your furnace on your own can be a lifesaver. If an HVAC professional is available, though, making the call is usually the best way to handle such situations.