:confused: I just replaced an old Honeywell thermostat in a 41 year old home... the wiring (2-wire) was not labeled or color coded nor was the screw type terminal it was connected to identified (no P/N on the old T-stat either). Since I am purely looking for contact closure I installed a Model # RTH221 Honeywell Thermostat in its place, I installed the two wires on the Y & G terminals and now the circuit is closed and the heater kicks on but it doesn't turn off... Yikes!! So I had no choice but to pull the cover plate off to make it stop. Now Im really sweaty and confused... do I install these wires on the Y - G - Rh - Rc or W terminals, its just a simple natural gas heater with no fan / AC / or any other options... it worked fine before, but ohh was that ole T-stat ugly!! Any sugestions here folks?

Patej

Just use RH and W. Let factory jumper in from RH to RC. You will use only two wires for your set up. Remember to put batterys in.

http://customer.honeywell.com/techlit/pdf/69-0000s/69-2060EFS.pdf