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My furnace will not turn on after changing the thermostat, but will operate manually. I changed the thermostat because the old one was cycling the furnace too rapidly (1 -5 min runs) . Wiring pics can be found here: http://imgur.com/a/V7u34#1
Sorry? Am I ready for what?
Ah.. definitely.. W on the stat connect to Y on the furnace (unchanged from old stat)
Sorry.. i was incorrect... W on the stat connect to the terminal seen in the second pic.
It's labeled TH-TR (beside black wire)
There are two wires at the Y terminal at the furnace, The orange goes to the Y at the stat, and the white wire leaves the furnace and goes to the AC compressor
yes, it connects to Rc on the stat.
Yes, this is accurate so far.
Also on Rc.
you see rc is 24v for cooling from a separate trans former. rc has nothing to do with the heat cycle...how about red...? was it on a r terminal as well?do you have the model of the old stat
update...I think I have it now...
old stat have 2 different r's?
Old Stat had R and Rc, The new one (honeywell rth6400) also has both. By default the R and Rc were jumpered, but the instructions said if the old stat had distinct wire for both to remove the jumper.
Apologies for the delay.. my fathers friend (who does hvac) just called and agreed that the circuits appear to be miswired.
Here's what he had me do (while breaker off): disconnect the Red wire from the stat, still at the stat, take black wire from Rc and put it into R (without jumper)
So now the red wire is not on anything in the stat, and is on R in the furnace. Black wire is on left valve terminal and R on the stat. The stat is set to heat, and the fan is on auto and the furnace appears to be responding to the stat.
Wiring unchanged form previous post the fan will not manually turn on, Connecting red wire to Rc as you suggested allows for manual fan control.