This morning I woke to a chilled house and realized my furnace is not working at all. I've checked the filter, breaker, thermostat, and shut the gas off then on in the furnace with no luck so far. Any ideas? Thanks in advance.

We need to go through the chain of events here and get a better idea of what is transpiring. Is your thermostat set to heat? When it calls for heat do you hear it "click" over? When it clicks over does the inducer(exhaust) motor come on? Please post additional information, thank you.

There is no clicking. I turned everything off, had my wife turn it on and turn the heat/thermostat up to 80 (inside temp was 64) and nothing, not even a click. :( I also had her turn the fan from the AUTO setting to the ON setting, and again, nothing. Thanks.

Are there any lights lit up on the control board?

I haven't tried that yet. That require removing the bottom panel I take it? Thanks again!

Yes, but after you take it off you will have to engage the safety switch in order to view the LED's

I took off the bottom door and the LED was blinking constantly. I pushed in on the safety, had my wife turn up the thermostat, and BAM, it all worked. I'm assuming it was that somehow the door became lose and the safety was disengaged. Could there be another possibility? Thanks for the help!! :D

Heh, heh... anything is possible. Make sure it continues to run after you make sure the door is secured properly. Glad I could help.

Sadly, this morning, it stopped again, and when I pressed in the safety switch, nothing, not even LED light. I didn't hear a 'click' at all when I pushed in the switch, so I'm ordering a new switch and hoping that was the problem.

You can bypass the switch until the new one comes in... normally not recommended but if you don't have heat it can be done. The safety behind it is due to the blower wheel can spin with the door off. Anyway, turn the power off to the furnace --> Remove both black wires from the switch and connect the two of them --> make sure you electrical tape them so they don't hit the furnace housing. Turn power back on and then turn stat to call for heat. If it works then you know for sure it is a faulty switch.

I finally got the new switch and installed it. Once replaced, the blowers would start up, ignite, and after only a few seconds, stop. This was with the thermostat at full heat. Being it was so early (late in the night/morning), I clicked off the gas at/in the furnace. I then turned off the thermostat. However, I didn't turn off the breaker. I went up to troubleshoot some more, and there was just constant clicking, like the ignition was try to start or something. Any help there? Nothing would work, the blowers wouldn't start, the fan tried to one time, but that was it. Thanks as always!

Hi
I have a trane xb80 furnace that was blowing cold air and as I read in this forum and according to the led code with flashing 4 times I found that I should change my swith limit , so I took out the switch it was l190f30 but the shop gave me l180f40 and told me it should work . I installed it on the furnace but it was blowing again colx air and whenever I was trying to put the temp above 23 it was stoping blowing air . And after a while it completely stop working . Now it's not working at alland it seams ghat there is no power in the furnace and the light is completely off . Please help we what to do ?