Eisenfaust8
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Been changing out old single pole thermostats with no problem until I got to this one. The old thermostat is labeled "Load-black" "Line-red". The black load on the old thermostat was wired together with the two in the left of the picture, for a total of three wires on one nut. The red "line" was wired to the black wire on the right. (For reference, the picture uploaded sideways. To the left is "up" and right is "down")
The cadet heater is below this thermostat. The two wires already twisted together originate from the top of the box, whereas the single wire on the right is from the bottom. I thought it was safe to assume that the wires coming in from the top were the hot "line" and the one going down would be load to the heater. But the way the old thermostat was wired the black load went with the two wires that go up and the red line went with the single wire going down.
I thought I'd be smart and use the voltmeter with a probe on the ground wire in the box and the other on the wires in turn. Both gave me a reading around 120-140. Shouldn't only the true "line" be hot??
Edit: I just pulled off another one from another part of the house. In this one the red is going to the two wires coming from the top of the box and the black is going to the single that heads down. Could the first one I posted about be wired backwards? Is it even possible to have one of these thermostats wired backwards??
The cadet heater is below this thermostat. The two wires already twisted together originate from the top of the box, whereas the single wire on the right is from the bottom. I thought it was safe to assume that the wires coming in from the top were the hot "line" and the one going down would be load to the heater. But the way the old thermostat was wired the black load went with the two wires that go up and the red line went with the single wire going down.
I thought I'd be smart and use the voltmeter with a probe on the ground wire in the box and the other on the wires in turn. Both gave me a reading around 120-140. Shouldn't only the true "line" be hot??
Edit: I just pulled off another one from another part of the house. In this one the red is going to the two wires coming from the top of the box and the black is going to the single that heads down. Could the first one I posted about be wired backwards? Is it even possible to have one of these thermostats wired backwards??
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