Trane XL90 Not Working, LED Flashing Normal

[rhodesrt]

I have a Trane XL90 that failed to turn on last night (0 degrees in Denver). I recently replaced the hot surface igniter and am trying to diagnose this problem.

I removed the cover and the LED is blinking slow which means normal - no call for heat. The thermostat reads 55 degrees and I have it set to 72. I am wondering if perhaps my thermostat is not sending a signal or if the board is failing somewhere.

Is there a reset button I can try or a way to bypass the thermostat to start the furnace?

Please give me some suggestions to try to heat my house.

Thanks

[fordrules]

Take the thermostat off and jump the red and white wire, or whatever color wires go to the W and R terminal on the thermostat. If the furnace fires with the wires jumped, you have a bad thermostat.

[rhodesrt]

Thanks for the advice. When I came home from work the furnace had already kicked on. Now I guess I have know way of knowing what may or may not have been wrong.

Can I expect this to be an intermittent problem or is there any corrective action I can take to ensure it doesn't happen again?

[fordrules]

Replace the stat. They're cheap and then you'll know for sure. These are what I install:
Non programmable:
http://www.hotfreshcool.com/focuspro_5000_demo.html
Programmable:
http://www.hotfreshcool.com/focuspro_6000_demo.html

The best thing about digital is there's no heat anticipator to set, and it doesn't matter if its level. I've had very good luck with honeywell, and the customers I put them in for seem to like them too.