Recently installed a noma programmable thermostat and same was working fine for three or four days but this morning the furnace kept running. Temp was set @67F but furnace was still running @ 79+F .The only way to stop the furnace was to manually shut it done.Why is it doing this and what must I do...

I have a Carrier Weathermaker 8000 and want to install a Honeywell Programmable Thermostat. The model I bought is RTH230B. Will this work with my HVAC unit?

I am replacing old thermo with Noma programmable one 52-2546-6. My old thermo has only white and black wire. Where they should go on Noma. Instruction say: common goes to Rh and the other to W. Is common always white wire? So white goes to Rh and black to W? They also have jumper between H1...