The flame rollout switch monitors the heat surrounding the burners. If the inducer fan motor cannot draw enough air through the burners, or if the furnace is not venting properly, the rollout switch...
The gas valve opens to allow gas to flow into the burner. If the gas valve is defective, the valve will not open, preventing the furnace from heating. To determine if the gas valve is at fault, use a...
The pressure switch closes when the burner has sufficient airflow. If the pressure switch isn’t working, it might not close when the proper airflow is present, causing the ignition process to stall....
Check the gas valve to ensure that it is turned on. If the furnace uses propane, check to see if the furnace has run out of gas.
Air Flow Problem
The furnace must have proper airflow through the burner in order to continue running. The furnace draws air from the surrounding area or from outside the room. If the furnace is located in a utility closet or in a cramped storage room, there may not be sufficient available air for the furnace to heat properly. If the furnace draws air from outside the home, check for an obstructions at the air inlet.
Incoming Power Problem
Check to see if there is power to the furnace. If there is no power to the furnace, check the furnace circuit breaker or fuse.
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