Troubleshooting Gas Furnace Ignition Problems

It’s the middle of a cold Ohio winter and your furnace suddenly stops working. While it could be some other problem, one likely culprit is your furnace ignition, the spark or flame that gets the appliance working. Finding out why your furnace ignition has gone on the fritz can be challenging, however. If you are willing to take the time to troubleshoot your furnace, you may be able to diagnose (or even repair) it yourself and save some money.

Here are some troubleshooting tips for common furnace ignition problems.

  • Check switches and breakers – A tripped or blown switch, fuse or circuit breaker could prevent your fuTroubleshooting Gas Furnace Ignition Problemsrnace from kicking on. A turned-off switch or loose access door also could be responsible for a malfunctioning furnace ignition.
  • Examine your thermostat – Make sure it’s set on the “heat” position and the date and time are right (if applicable). A digital programmable thermostat’s display will be blank or flashing a code.
  • Confirm that your furnace’s gas valve is open – The valve is part of the furnace ignition system and will be visibly marked on the side. Gas must be flowing for the light to stay on. In the “on” position, the valve is parallel to the pipe.
  • Look at the pilot light – A standing pilot light will be evident when the combustion chamber door is open. If the light is out, re-light according to the owner’s manual or call your HVAC technician. If you have a newer furnace, is very likely has electronic ignition rather than a pilot light.
  • Turn your thermostat’s fan switch to the “on” position – If your furnace still doesn’t work after this step, the problem could be with the furnace ignition, failure to get power or a faulty fan motor. If your fan doesn’t work, heat will not come out of the registers.
  • Take note of any unusual noises – A banging sound could indicate something is lodged in the ducts or a metal flap is loose. A squeaky motor might mean a belt needs readjusting and a grinding sound could signal shot bearings.
  • Inspect your furnace’s drain lines – Remove any mold or debris to keep the drain line open.

For more expert advice on troubleshooting your gas furnace, please contact us at Geisel Heating, Air Conditioning and Plumbing. We have been serving the greater Cleveland area with honesty and integrity for over 78 years.

Our goal is to help educate our customers in Cleveland, Ohio about energy and home comfort issues (specific to HVAC systems).  For more information, download our free Home Comfort Resource guide.

For those Do it Yourselfers who would rather take control of your own indoor comfort, you can shop our online store for replacement parts, products and accessories!

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