Community Forums

lockinload · 10-01-2018, 07:28 AM

Typical Atwater furnace. Thermostat is not recognizing the zone 1 furnace. I have tested the furnace by jumping the two blue wires (thermostat) and it functions properly. Guessing a ground issue but don't really know how to test. I have 0 ohms at the negative connection from the motor so that is good. Now what? I suppose I should pull the plug that supplies the 4 wires (2 blue, one red and one yellow), could be a ground issue there.

Bad thermostat?

Skip426 · 10-01-2018, 09:21 AM

Going to need all your coach info to provide any help .

Year , manufacturer, t'stat brand ; Atwood ? Duo Therm ?

Is your thermostat a four button unit.

A recent post by a Monaco owner had his ; t'stat not seeing furnace ; issue track back to a bad wire in the front roof air conditioning unit.

bamaboy473 · 10-01-2018, 11:33 AM

For unexplained reasons, the fuse in the thermostat got removed and re-inserted and it fixed a mis-reading issue. Had to do it regularly until I just bought a new thermostat.

Try removing fuse to hard-reboot it?

lockinload · 10-01-2018, 12:18 PM

Quote:

Originally Posted by bamaboy473

For unexplained reasons, the fuse in the thermostat got removed and re-inserted and it fixed a mis-reading issue. Had to do it regularly until I just bought a new thermostat.

Try removing fuse to hard-reboot it?

I will check that out. Thanks, a new thermostat can't be too expensive even if it needs replacing. My money is on a bad ground somewhere...the question is where.

Old-Biscuit · 10-01-2018, 12:22 PM

Thermostat is JUST a switch....when it makes up it connects the 2 blue wires

You manually connected the 2 blue wires and furnace worked

Thermostat doesn't.

lockinload · 10-01-2018, 01:14 PM

Quote:

Originally Posted by Old-Biscuit

Thermostat is JUST a switch....when it makes up it connects the 2 blue wires

You manually connected the 2 blue wires and furnace worked

Thermostat doesn't.

While this is true, I jumped those blue wires at the motor. Those blue wires run to a plug and that plug runs to the thermostat. What we know is, the problem lies between those two points. I could have a problem at the plug. That plug may connect to something else or it may go directly to the thermostat, I don't know. I guess I'll start chasing.

Old-Biscuit · 10-01-2018, 01:35 PM

Quote:

Originally Posted by lockinload

While this is true, I jumped those blue wires at the motor. Those blue wires run to a plug and that plug runs to the thermostat. What we know is, the problem lies between those two points. I could have a problem at the plug. That plug may connect to something else or it may go directly to the thermostat, I don't know. I guess I'll start chasing.

Pull t-stat cover so you can expose the wiring.
Connect furnace and DC + wires.
Furnace runs or doesn't

http://rvsitesupport.com/insight/man...hermostats.pdf