Hello Everybody - Merry Christmas,
I had this same problem last year, it fixed itself till now,
Medium size Reznor, 20 years old, has worked fine, just stopped working, pilot is on, jumping the 2 wires from the furnace at thermostat does nothing, no clicking - nothing.
Last year did the same thing, I changed the stat, went up and jumped wires at the furnace nothing, it just started working, I switched the stat back to the original and it continued to work until now.
Any ideas would be appreciated -