Heating, Air Conditioning, Fridge, HVAC/high eff. lp furnace


QUESTION: thermostat calls for heat, furnace tries to start but fails to lite all 3 burners, lights the left but fail on center and right. if i remove the back cover behind the burners it will light all 3 burners. on the circuit board the red led does not indicate an error has occurred. the blower fan keeps running and after about 1 minute it will try to start again. most of the time it will start after 3 to 7 tries.
thank you for any help you can give memo3m5

ANSWER: Randy, you need to clean the flame sensor, Check how your burners are lighting, they should all light pretty much at the same time or kind of like a sweeping wave.

---------- FOLLOW-UP ----------

QUESTION: I have cleaned the sensor. the unit shuts down before the flame gets to it at the right burner. I forgot to mention it in the first question.

There is a small channel that runs across the front of the burners at burner level, the channel helps spread the flame from burner to burner fast enough to light the burners  and not shut off the gas.
Check the channel for blockage or out of line?

Randy, nothing wrong with my Knowledgeability, I'm telling you what to do to solve the problem you describe.
The fan has nothing to do with it.

Heating, Air Conditioning, Fridge, HVAC

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Jim Barnhart


Fifty + years conditioning the air.


Answer questions about , residential and commercial. Answer questions about sheet metal fabrication. Fifty years plus experience. No answers for oil equipment, No answers for kitchen appliances, No answers for laundry appliances, I don't specialize in one particular area of the HVAC area, I'm more of a General Practitioner, Limited in refrigeration/

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