Re: Furnace comes on for 1 min then kicks off, repeats...
MY FURNACE WOULD RUN FOR ABOUT TWO MINUTES , THEN THE BURNER WOULD GO OUT BUT THE BLOWER WOULD CONTINUE TO RUN , LONG ENOUGH TO COOL THE FAN LIMIT SWITCH DOWN , THEN IT WOULD START THE PROCESS ALL OVER. WHAT FIXED MY PROBLEM WAS THE SECONDARY HEAT EXCHANGER THAT IS LOCATED JUST ABOVE MY BLOWER MOTOR WAS PLUGGED WITH DIRT , WHICH RESTRICTED THE AIR FLOW , CAUSING THE FAN LIMIT SWITCH TO REACH 200 DEGREES AND SHUT THE BURNER DOWN . YOU'LL HAVE TO TAKE THE BLOWER MOTOR OUT TO GET TO IT , BUT MY FURNACE IS RUNNING PERFECT NOW
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Hello, sounds Like the Furnace is tuning off due to the limit switch or rollout switch opening. A limit switch and rollout switch are safety swtiches that will turn off the furnace if it gets to hot or the burners flames are abnormal. Usually a weak blower motor, dirty blower wheel , dirty burners or even a crack in the heat exchanger can cause this problem. Best bet is to call a hvac technician and have them check it out.
Check by turning the unit off and turn the fan to on. Do you hear the noise now? The noise your hearing could be coming from your combustion fan assembly instead. Newer furnaces have a in-shot burner and are nosier than the old style of heater.
Make sure a back draft in the flue is not happening. Wind can blow it out until the flue heats up. The flame sensor may not be close enough to the burner flame. It may be weak and need to be replaced or if its an optical one it may be dirty and not see the flame very well. Its not wasting much gas but it puts extra wear and tear on the gas controls, is noisy, and, as you said, blows cold drafty air. A gas control system that has issues of any kind is not real safe. It needs to get fixed.
Remove all power from the furnace, it is likely the brain in the furnace is need of being reset, from the battery replacement, why did you change the battery, was there an indicator telling you to change it?
Many times just removing all the power to the furnace will do the trick with a reset, if not let me know and we will go from there, but it sounds like the main brain is confused or bad, more likely confused, so try the power removed first.
I have serviced these furnaces for 20 years and I can tell you most of these models did not have diagnostic lite on them. (although some did, especially if the control board has been replaced) The problem is most likely a bad 3 wire pilot. This will cause exactly what you describe. 2 things to consider though. 1, If you were to replace the pilot don't get a cheaper knockoff. In my experience these do not last long at all. Get the right one from a carrier dealer. It will cost more but be much more reliable. 2 What is the condition of the secondary heat exchanger? Most if not all of the sx series had issues with the secondary heat exchangers rotting out and leaking. If the furnace is out of warranty you would be much better replacing the furnace as the cost of replacing the secondary heat exchanger will probably be almost the same as a new furnace. ( those babies are EXPENSIVE!)