On Tuesday, December 10, 2013 4:12:10 PM UTC-5, David L. Martel wrote:
Danny,





I went down there and noticed

the door was off.



How did that happen? Who left your furnace open and why?



That's a good question. Did it come off at some point in the
diagnostic process or was it off to begin with and the cause
of the whole problem?




When I put the door back, the blower just blew incessantly.



Ok, you've got electricity to the furnace. No blown fuses etc.



So I took the door back off, and pressed the white switch that gets

pressed when the blower door is on, and the blower just kept blowing

for as long as I held the switch pushed in.



Back upstairs, teh cover is still off the thermostat, so the thermostat

settings are still at HEAT (versus OFF, COOL) and AUTO (versus FAN ON).



At this point the fan should not be on.


The fan is probably on because he's been screwing around with the
thermostat and now has something screwed up there.

With a simple old mercury thermostat like that, there isn't
much to fail. I've never seen one that just stopped working.






Read section IV of the manual. It explains what should occur and when in

the heating process.

Confirm that you have gas.

Find the furnace switch in your breaker box. Turn it off. Give it a few

minutes. Turn it back on



Dave M.