View Full Version : Furnace burner lights but goes out before the coupler gets hot
Big T
Jan 25, 2009, 08:50 AM
Hello,
My furnace (RUUD) Starts up properly sequentially. The power vent lights, the forced air begins, the glow plug lights , then the gas is delivered. The flames ignite. Perfect! Then the glow plug shuts down and the flame goes out. The timing of these evens seems to be incorrect. The glow plug is on long before the gas galve opens. There is little time for the thermo coupler to get hot. IF I HEAT THE THERMO COUPLER WITH A TORCH THE FURNACE STARTS UP PROPERLY.
Is there a timer ajustment for all these funtions?
Periodically the second burner will not ignite, Why?
wmproop
Jan 25, 2009, 09:00 AM
Maybe the thermocoupler is to far away from the igniter,, maybe the thermocouple needs replaced,,
Periodically the second burner will not ignite, Why? Maybe the burners need cleaning and the gas orfface,, it's a hard guess without being there
Big T
Jan 25, 2009, 09:59 AM
Can the timing of the start up sequesnce be changed?
hvac1000
Jan 25, 2009, 10:12 AM
can the timing of the start up sequesnce be changed?
No it is programed for proper sequence of operation.
Are you sure you have a thermocouple or a flame sensor. Since you did not post the exact model number it could be a flame sensor. I am including a pic of a flame sensor. They can all look different but the pic will give you an idea. Some of them do look like a thermocouple. If you have a White Rodgers system then you might have a mercury control .
wmproop
Jan 25, 2009, 10:42 AM
(quote)The power vent lights, the forced air begins, the glow plug lights
I had never seen a furnace with a blow plug and a thermocouple,, so I had to assume you know what you have,,
wmproop
Jan 25, 2009, 10:44 AM
hvac1000,, how do I get in on getting paid 5 cents each time you show that picture?
Lol,, :):):),
hvac1000
Jan 25, 2009, 11:08 AM
It is only 2.5 cents. LOL
Big T
Jan 25, 2009, 12:41 PM
It has an electronic igniter (glow plug?) the pic of the heat sensor with the end bent at a right angle is theone I have. So cleaning it will work?
hvac1000
Jan 25, 2009, 01:28 PM
so cleaning it will work?
Cleaning it will work IF it is dirty and is not sensing the flame which is causing the unit to drop out. Steel wool,scotch brite pad,sand paper will shine it up and make it conduct better.
greghvacguy
Jan 25, 2009, 08:28 PM
You need to clean cross lighter for the burners. If all the burners don't light then it will drop out.
Big T
Jan 25, 2009, 08:56 PM
Cleaned the flame sensor. Seems to have fixed the problem, Thanks so much... its nice to have heat here when the weather is dropping to -1 f tonight thanks again, Big T
hvacservicetech_07
Jan 25, 2009, 09:57 PM
Good deal! I hear you,it's about 5 degrees here.
hvac1000
Jan 25, 2009, 10:59 PM
cleaned the flame sensor. seems to have fixed the problem, Thanks so much...its nice to have heat here when the weather is dropping to -1 f tonight thanks again, Big T
I am glad the information I posted to you worked now you can keep warm.
MarkwithaK
Jan 25, 2009, 11:03 PM
I am glad the information I posted to you worked now you can keep warm.
Admit it, you were just looking for an excuse to use that flame sensor pic again. So do they pay you on a regular schedule or is it an annual thing?
hvac1000
Jan 26, 2009, 01:48 AM
It is like a public service job. Every two weeks. LOL