Old thermostat wiring
January 15, 2009 9:37 AM Subscribe
Replacing the old mercury thermostat in our old house with a programmable one for an oil furnace. The old one is a two wire hook up, one red/white and the other black. What would be the correct configuration to the new thermostat? Black to R, Red/White to W? I've searched high and low for the answer.
posted by Heatwole to Home & Garden (16 answers total)