Wood/Oil Combo Thermostat Wiring

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BushPilot87

New Member
Jan 17, 2022
1
Newfoundland
Hoping somebody in here can help me out. Just bought a new house and it has a Newmac wood/oil combo furnace. I picked up a couple of basic non-programmable digital thermostats to replace the decades old mercury thermostats controlling the furnace. The old stats are side by side on the wall and they share three wires: black, red, and white. The black runs to the right side of the wood stat and the white to the left side (when viewed from the front), then there’s a white jumper to the right side of the oil stat and the red runs to the left side.

I did find a wiring diagram for my furnace online, but it seems like the red and white wires are swapped on my unit. Just want to make sure I connect to the right terminals on the new thermostats as the old ones have no letters or labels on the terminals. And before somebody asks, the reason I want to change them is because the digital ones will show me the exact temp setting as well as current indoor temp, and I’ll also be able to see when the oil stat is active.

Any help or advice would be greatly appreciated!

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