replaced thermostat furnace doesn't go no with new t-stat. why?
Just replaced a manual York thermostat with a Honeywell 7400D. I connected the wires exactly the way they were in the old one (G to G, Y to Y, W to W and R to R (which is jumpered)). All systems work except the heat furnace which won't kick in (even
What you have to do is look inside of the furnace, to see what colors are connected on the board. If you still have a problem you may call me at 214-914-4969 or visit my web site at www.gmsair.com