How to Troubleshoot Lennox Furnaces


Lennox furnaces are designed for use in both homes and businesses and come with a variety of options, such as a stainless steel secondary heat exchanger, variable speed inducer, quiet motor, electronic control panel and automatic ignition in some models. The furnaces are sold in many places, including online and home retail or heating and cooling supply stores or dealers. Owners should find that operating and maintaining the furnace is generally straightforward, but if issues do arise, many minor issues can be resolved through some troubleshooting.

Things You'll Need

  • Clean cloth(s)
  • Vacuum with brush attachment
  • Dishwashing liquid
  • Soft brush
  • Plug the Lennox furnace into a grounded power outlet if there is no function. Replace or reset the fuse or circuit breaker as needed.

  • Turn the furnace thermostat to a warmer temperature than the ambient air temperature if there is power and heat to the furnace but it is not running. Set the thermostat to "Heat" and the fan speed to "Auto" to allow the furnace to run as necessary to maintain the warm temperature.

  • Clean the filter if the furnace is not heating or working as expected. Disconnect power to the unit and open the access panel. Slide the filter out and use a vacuum with a brush attachment to clean off excess dirt or debris. The filter can also be washed with dish washing liquid and warm water, rinsed well, and air-dried before returning to the furnace. Note that filters marked "Disposable" can simply be replaced with a new filter, available for purchase at many hardware or home retail stores.

  • Check the blower wheel and fan if the furnace is running noisily or not working as needed. Disconnect power and open the access door. Use a soft brush to clean off the blower wheel and fan. Reconnect the front access panel.

  • Clean the vents and grilles on the furnace with a clean cloth if there is loud operation or poor air flow. Find the return-air registers and vents in the home and clear away objects, furniture or other items that may impair air flow.

  • Contact Lennox for assistance if the problem persists.

Tips & Warnings

  • Turn off the furnace if gas is detected. Leave the house and contact the gas company or fire station immediately.

Related Searches


Promoted By Zergnet


You May Also Like

Related Searches

Check It Out

22 DIY Ways to Update Your Home on a Small Budget

Is DIY in your DNA? Become part of our maker community.
Submit Your Work!