My "top of the line" Comfortmaker has given me nothing but problems since installation! This thing didn't last 5 years before it started acting up. The controll modual say's nothing is wrong, yet the gas flame turns on and off every 45 seconds, thus burning out the ignitor. Every limit switch and sensor has been replaced with no luck. The dealer then scamed me for a new heat exchanger, which turned out to be fine once removed. I have stopped payment of the check, and then was insulted by the manufacturer when I called them for advice!! They refused to give me any info on this problem with the electronics, which I have now found out has been an on going problem with this brand. My advise is to stay clear from any product that has this kind of support behind badly designed and tempormental furnace!!!