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Blinking LED light is 3 red flashes

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The system tries to run and after 3 unsuccessful attempts, it goes to sleep for an hour before it attempts to run again. If we turn on our gas fireplace during the hour, the system always seems to relight.

On 2013-01-26 Karl wrote:

Shut the power off at the furnace. remove top cover. locate flame sensor to the left pointing down in front of the burner tubes and clean it by using steel wool. Turn the furnace back on and let the furnace cycle thru all stages, keep in mind the flame sensor rod (thermal-couple) informs the controller there is main flame after ignition. If the rod is dirty or faulty the main gas valve will close after four seconds even though you had flame and shut off. This will repeat four more times if the flame sensor is bad. The furnace will repeat five more times in sixty minutes. (Sure Fire technology) The Flame Sensor part is only about $15 to $20. Part number 52w29. Find one online and keep it nearby for future use.

This should work for you.

Here is a link to show what those flashing lights are trying to tell you thru the sight glass on the bottom panel.

http://www.sbeelectricandhvac.com/lennox-furnace-g60uhx-series-units-diagnostic-led-error-code/

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