My furnace shuts down randomly and does keep house at selected temperature. When I push to raise the temp there is no response from furnace after it has shut itself down. The thermostat is a cheaper model from Target installed last summer. The furnace is 4 years old. The first repair man cleaned the ingnition pin, the second was puzzled since the furnace started right up... he suggested maybe a thermostat malfunction. He checked to make sure it was installed correctly - it was.

Last night my van car alarm was activated in the garage at 2:30am (never has happened in 6 years - no one was in the garage) AND the furnace had shut down. I turned the power off, shut off gas and turned thermostat off for 10 minutes. Then turned gas on, power to furnace on and then turned on the thermostat but no reactions bit left everything on. Went back to bed and at 6:30 am the furnace came back on by itself.

HELP!

Last night my van car alarm was activated in the garage at 2:30am (never has happened in 6 years - no one was in the garage) AND the furnace had shut down. I turned the power off, shut off gas and turned thermostat off for 10 minutes. Then turned gas on, power to furnace on and then turned on the thermostat but no reactions bit left everything on. Went back to bed and at 6:30 am the furnace came back on by itself

Do you have a ghost? I guess the car and furnace are connected??

If the service men who are at your home cannot figure it out then it would be impossible for me to figure it out by remote control. If you still have the original thermostat I would hook it back up for awhile to see if that solves the problem.