Hi again, I posted my situation a few days ago with very little response, so I wanted to follow up again before calling out a technician. I have a Goodman gas furnace, about three years old. It has electronic pilot ignition, which works fine and will enable the burner flame... the problem is the burner will shut off within two-three minutes... the furnace will again repeat this cylcle a number of times... I've never allowed it to continue beyond three cycles... I simply turn it off. I've read most of what's been posted on the subject and it sounds like to me it could be a bad "limit switch" or that it simply needs to be "reset" from a overheating shutdown cycle. Apparently, my air filter was extremely dirty, so, I'm wondering if I had inadequate airflow, which may have triggered an overheating sensor or something. I've since replaced the filter and the air flow seems good, but alas the burner flame contintues to cycle off before adequate heating. I also increased the cycle time from the thermostat... no change. Please, please, help me if you can. I am financially strapped right now and would prefer to correct the problem myself if I can. We had another night of freezing weather -32 degrees... I need your advise. Thanks, Bruce.

Rather than start a new thread, you would have done better to check the limit switch as Northern Heat suggested in the first thread. If it is bad, the furnace will do just as you say it is.

It is better not to mess with the thermostat until you are certain the problem isn't in the furnace. Problems are much more likely to be a failed switch or relay than an adjustment changing.

I agree with the above. Time to call for service or replace the defective fan switch.