, posted Sat 19 Jun 10:55
I am replacing a Honeywell T841B1000 with a Honeywell CT3611. My old thermostat does not have a C wire connected to it, but I need this for my new thermostat. I have only Blue and Black wire which could be the C-wire. Is there a way to test these with a multimeter or other method to determine which wire is the Common? All other wiring on the new thermostat fits correctly.
Replies:
Xenos Webmaster
"Re(1):Thermostat Wiring"
, posted Sat 19 Jun 16:58
Go to the furnace and see if a wire conects to C and if it does what colour is it.
"Thermostat Wiring" 
