AC & Heat Pump

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Furnaces, Boilers & Radiators

Pilot Reignition Furnace
Standing Pilot Furnace
Hot Surface Ignition Furnace

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Home Owners Section

HVAC Technical Support Furnace Troubleshooting.

You can use the menu options on the left to navigate or the links below. If you are a home owner, you may also visit the HVAC Technical Support homeowners section.


US Air Distributors sells furnaces manufactured by York, Luxaire, and Coleman, to the left you will find some basic trouble shooting techniques for three different types gas furnaces.

Standing pilot furnaces: these are used in older furnaces, they typically used a thermocouple or thermopile to prove that the pilot flame was lit. The pilot was always on, and when the thermostat called for heat the gas valve would open allowing the burners to light.

Pilot Re-ignition system: these systems typically used a thermal activated warp switch. If the pilot light dropped out. The switch position would change allowing voltage to a spark igniter that would Re-ignite the pilot light.

Hot surface ignition: this system has no pilot light. It used a high heat element that glows red-hot and directly ignites the main burners. This system uses flame rectification to prove that the flame is light.

Below you will find links to troubleshooting presentations on various furnace components.

Also please review our troubleshooting circuit board section for presentations on the furnace circuit boards found in these products.