Gas and Oil Home Heating Furnaces - Thermostat
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jessep
12-23-04, 03:53 PM
Lennox C23-31-1 Gas Furnace (1997 mfg.)
Recently, my HVAC system has been acting up. THe system will not kick on after going below the temp set on thermostat. The ignition system will not even activate (no green LED), indiciating to me that it's a thermostat problem still. I replaced the thermostat with a Hunter model from Lowe's on Sunday.
Even with the new thermostat, sometimes, I can turn the thermostat off "heat" and back on and the furnace will operate. Sometimes it won't. I tried regightening the red and white thermostat wires on the outside screws of the furnace with the same works/don't work results. Same with switching back and forth the electrical switch on the outside of the unit.
When the unit does "kick on," that ignition system turns on (LED on), pilot light works and I get a good flame followed by the fan blowing air perfectly.
There is still plenty of give on the electrical feed from the wall to the furnace downstairs. I am thinking maybe I need to cut a piece of it, restrip the wires and maybe the fresh contacts will work?
Should I maybe replace the upstairs thermostat again, or is there a larger issue with the voltage needed to kick the unit on that needs to be addressed by a professional?
Thanks.
Recently, my HVAC system has been acting up. THe system will not kick on after going below the temp set on thermostat. The ignition system will not even activate (no green LED), indiciating to me that it's a thermostat problem still. I replaced the thermostat with a Hunter model from Lowe's on Sunday.
Even with the new thermostat, sometimes, I can turn the thermostat off "heat" and back on and the furnace will operate. Sometimes it won't. I tried regightening the red and white thermostat wires on the outside screws of the furnace with the same works/don't work results. Same with switching back and forth the electrical switch on the outside of the unit.
When the unit does "kick on," that ignition system turns on (LED on), pilot light works and I get a good flame followed by the fan blowing air perfectly.
There is still plenty of give on the electrical feed from the wall to the furnace downstairs. I am thinking maybe I need to cut a piece of it, restrip the wires and maybe the fresh contacts will work?
Should I maybe replace the upstairs thermostat again, or is there a larger issue with the voltage needed to kick the unit on that needs to be addressed by a professional?
Thanks.
Jay11J
12-24-04, 12:48 PM
I've never been a big fan of store brand t-stats.. Get the real one like Honeywell.
Just take the r and w wire and connect them together.. see if it works.. if it works, then it's the stat.
If still the same then it's something in the furnace.
Make sure you got a good ground.. These new furance are funny about not getting grouned well.
Just take the r and w wire and connect them together.. see if it works.. if it works, then it's the stat.
If still the same then it's something in the furnace.
Make sure you got a good ground.. These new furance are funny about not getting grouned well.
jessep
12-29-04, 12:55 AM
Acutally, it was the relay circuit board. Thermostat was sending correct voltage down to furnace and it would light correctly.
It was just odd for it to just quit lighting when stat would send power down to light furnace all of a sudden. And when it didn't fix itself with new stat, I knew it had to be something with the furnace itself.
Thanks for all your help though.
It was just odd for it to just quit lighting when stat would send power down to light furnace all of a sudden. And when it didn't fix itself with new stat, I knew it had to be something with the furnace itself.
Thanks for all your help though.