Coming to the collective for help. We are having our basement finished. Last night at some point we lost heat. It's propane (plenty of fuel). There is power to the furnace. But the Aprilaire zone control is not showing any power. I do get a red light when I touch the thermostat wires. The zone control has an LED to show power and it is not lit.

The only thing I can think is that the dry wall guy did remove and put back the basement thermostat. We had the basement zone added when we built last year so it already had heat that was working. I'm at a loss and it's Sunday so getting someone is not easy. Any suggestions?

This message has been edited. Last edited by: frayedends,

Try reinstalling the thermostat? If it worked prior to removal, but stopped after removing, it's a pretty safe bet. In my house my furnace will not operate without a properly installed t-stat.

Checked the thermostat. I removed and reconnected all the wires. Still no power on the zone control unit. Strange.

So the thermostat removed was a remote sensor, not your actual thermostat? Are you able to check and see if you have 24v present? Maybe they tried the transformer? Does the main t-stat light up?

Problem solved. There was a 3 amp automotive type fuse in the furnace that was blown. I was looking for a reset switch but nope, a fuse. Thanks guys. I almost missed it.

Congrats on properly diagnosing, and fixing it yourself!

quote:

Originally posted by frayedends:
Problem solved. There was a 3 amp automotive type fuse in the furnace that was blown. I was looking for a reset switch but nope, a fuse. Thanks guys. I almost missed it.

Any idea about why the fuse blew?
Need to understand why it blew, or you may have this issue again.


-K

quote:

Originally posted by Kranky:

quote:

Originally posted by frayedends:
Problem solved. There was a 3 amp automotive type fuse in the furnace that was blown. I was looking for a reset switch but nope, a fuse. Thanks guys. I almost missed it.

Any idea about why the fuse blew?
Need to understand why it blew, or you may have this issue again.


-K

Probably from the drywall guy shorting out the wires from the tstat.

quote:

Originally posted by PowerSurge:

quote:

Originally posted by Kranky:

quote:

Originally posted by frayedends:
Problem solved. There was a 3 amp automotive type fuse in the furnace that was blown. I was looking for a reset switch but nope, a fuse. Thanks guys. I almost missed it.

Any idea about why the fuse blew?
Need to understand why it blew, or you may have this issue again.


-K

Probably from the drywall guy shorting out the wires from the tstat.

This was my guess.

quote:

Originally posted by Kranky:

quote:

Originally posted by frayedends:
Problem solved. There was a 3 amp automotive type fuse in the furnace that was blown. I was looking for a reset switch but nope, a fuse. Thanks guys. I almost missed it.

Any idea about why the fuse blew?
Need to understand why it blew, or you may have this issue again.


-K

Drywall guy removing the stat without shutting off the power first.
R - red power wire to C- common wire touched each other = blown fuse.