"duradrinx" wrote in message
om...
duradrinx had written this in response to
http://www.thestuccocompany.com/main...ma-165203-.htm
:
I really hate to bump up a very old post. But I am having this exact
issue.

I had replaced my old mercury thermostat and shortly after this started
happening to me. I had the furnace looked at 3 times, 2 differant
companies. All three techs told me it has to be the thermostat. Well
after trying 2 more thermostats, differant manufacturers. Nothing has
changed.

Did anyone find a solution to this?

I suggest you put back the old thermostat.

But one "clue" might be found by asking yourself how the thermostat gets the
power (I ASSume it is one of those electronic gadgets with a display.)

The old mercury thermostats are near idiot proof. They can even work on
"milivolt" system where the power to turn on the gas valve comes from a
thermopyle soaking in the pilot flame. If it just calls for heat it only
needs 2 wires. If it allow you to turn the fan on it only requires 3
wires. If there is an A/C with the furnace it only requires 1 more wire.