In this flame sensor video you will see the sequence a furnace will take when you have a flame failure. The burners will try to light 5 times then go into lock out for 3 hours before it will try again. Another thing to keep eye on is the diagnostic light on the circuit board of the furnace located middle to the left side. You will see it flashing different codes count the flashes as it changes 4 times. short and long flashes

• 1st code 12 meaning blower delay time, will change to next code solid light on after 34
• 2nd code will be on solid for call for heat, flames fail and change to code 34 after 50 sec
• 3rd code will be 34 for ignition proving failure, will change to code 14 after 4th try to ignite after 2 min 48 seconds
• 4th code 14 ignition lockout. The furnace will be locked out for 3 hours before it tries again, you will need to reset power for furnace to try again by shutting power off then back on after a couple minutes or turning temperature down then up again.
  95 percent of the time the problem is only a maintenance issue and just needs the flame sensor cleanedClick on this link to see the video furnace flame failure video

Click here to see my Post on protecting your home ” Alarm for home”

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Tagged: flame failure, Flame sensor, ignition problem, ignition problems