[Dougalass]

Tried replacing the thermostat to find five wires going in to a double pole thermostat. Four of the five have 120V on them connected to two breakers. The one wire with nothing doesn't go to ground but was connected in to the load side. I noticed two white wires with wire nuts on them in the box. One with a red wire that is hot 120. The old thermostat did not work correctly but did work as long as it was turned almost all the way off. If I turned it up at all it would not turn off no matter how hot the room got. All of the other thermostats in the house are single poles. Its a pretty old system
Thanks for any insight.

 

[beenthere]

A pic would make it easier to explain.

Sounds like a typical double pole line voltage thermostat. 2 of the wires on it are of course from the heat. These will be hot all the time, as the other end of them has the second line feeding through the heater.

 

[Dougalass]

A pic would make it easier to explain.

Sounds like a typical double pole line voltage thermostat. 2 of the wires on it are of course from the heat. These will be hot all the time, as the other end of them has the second line feeding through the heater.

 

[Dougalass]

So I guess my question is how should I wire it then? Obviously one line voltage on one side. Then just the element wire? I still don't understand why it would have two line voltage pairs on two breakers. Is it possible it has been wired wrong for a long time? The red wire on the right coming from the heater wires are hot all the time with 120. Thanks

 

[beenthere]

Fairly standard wiring in that box.

One way they are sometimes wired. One side of the breaker feeds the heater directly as far as not through the thermostat. The other side of the breaker goes to the line side of the thermostat.

How many heaters does that thermostat control. Sounds like it may be controlling 2.

 

[Old Thomas]

Does the thermostat have an “off” position or simply a temperature range? If it is the former, it is a double line break type. If the latter, it is single line break.