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Monday, November 11, 2013

Once the weather turns cold across Chicagoland, one of the most common calls to an HVAC contractor is about a furnace that won’t ignite. Use this guide to help you identify why the furnace won't kick on and what steps you can take to get the heat back on sooner, rather than later.

While the principles of fuel combustion, heat production, transfer and movement and venting are the same, regardless of a furnace’s age, there are significant differences in component design and heating performance of older furnaces, versus new furnaces. Use the tips that best fit your situation.

  • The first step to take is to make sure the thermostat is in heating cycle. If you have recently installed a new thermostat, there may be an issue with loose wire connections or incorrect contacts.
  • If your thermostat is displaying an error code, write down the displayed code, and check the thermostat operations manual for the cause and remedy.
  • Check the circuit breaker for a tripped breaker. Furnaces do require electricity in order to operate.
  • Take a look at the dial on the gas valve where the gas line enters the ignition. The dial should be in the “open” position.
  • If you have an old furnace with a standing pilot light, and you cannot get it to relight, a safety interlock may be preventing ignition. Turn off the gas valve, and call your Comfort24-7 service provider.
  • Newer furnaces typically use an electronic hot-surface igniter, rather than a standing pilot light. Hot-surface igniters typically last three to five years. It’s wise to keep a spare on hand.
  • If your furnace uses sidewall venting, check the venting intake and exhaust pipes outside the home for obstructions, such as snow and ice accumulation. If sidewall venting is or becomes obstructed, the furnace will not turn on or will shut down. A sagging exhaust pipe may accumulate condensate, which, too, is an obstruction. The furnace will shut down and will not restart until the issue is remedied.

If your furnace won't ignite or for other HVAC issues in your Chicago-area home, contact a service provider.

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