Burners on for 30 seconds & shuts off...

[dwasylkiw]

I have a TRANE (model # BLU080E942B1)Upflow Warm Air Gas Furnace that is 18 & 1/2 years old.
I relit my pilot yesterday; the burners come on normally and stay lit for about 30 seconds and then turn off. The blower doesn't come on. The blower does work in the A/C mode. Last year I had the same problem and I was told to increase the high temp. setting on the "Limit Control" device. This worked last year but I don't know if this is the correct approach to this problem. I'd appreciate a second opinion and advice on proper settings for the Limit Control device.

Thank You.

Daniel G. Wasylkiw

[Hube]

When a furnace Burner starts it will keep ON until the thermostat is almost (anticipator setting) satisfied, then shuts the burner OFF.This usually will take approx 3-5 minutes on a normal cycle. When the burner has run a minute or so the blower should start up( FAN ON ) (at approx 125 + - degrees) and circulate air through the ducts,etc. The blower will continue to run until the air in the furnace has reached the FAN OFF point which is approx 90 + - degrees. In case of a fault to the blower etc, the HIGH LIMIT will cut the burner off, if, or when the temperature within the furnace reaches approx 185 + - degrees. In your case the problem could be in the adjustable control setting, or a faulty control. Hube