We were having problems with our furnace not kicking in, we were having to go down and hit the reset switch whenever we wanted it to kick on (which was pretty often with -30 windchill) so we replaced the thermostat. Now it won't shut off. We replaced with the same kind of thermostat, Honeywell, dial not digital. To be honest. with the windchill what it is and the fact that our house is not well insulated (we have a slumlord) it is not ever hitting 70 degrees. But even when we turn the thermostat down to 60 so it should/would cut off to let the furnace "rest" and cool, it is not shutting off. Have checked, double and triple checked that it is installed correctly. Am concerned with letting it run ALL the time that it could catch fire. Any advice would be appreciated