My Trane XR80 Furnace started back in 2008 about one or two times during the winter tripping the safety reset button. I have been paying up to $100.00 every time I have someone come out and look at it. All they do is clean inside and push the reset switch. I finally had a guy show me the reset switch and I have been doing it since. But now we can not turn our temperature up above 68 degrees or it will trip the reset switch. When the switch is tripped, the red light will flash 4 quick times and then a pause and then keeps repeating this sequence.

By now with all the resets the safety reset switch has weakened to a point where it will trip easier or more often. Replace the switch and see if it trips anymore. You might be surprised in the fact that a new switch solves the problem. NOTE: Make sure the replacement is the same settings as the one you are replacing. It will be labeled something like 170 degrees F. The 170 is a number I just picked out of the air since it could be 180 or 190 or whatever but the number or setting is important to be the same that is printed on the old one you removed..

You also need to pull the blower out and clean it. Make sure to check anything that can cause a restriction of airflow.