Someone gave me this digital thermostat which was used & has no instruction papers. I have a Goodman Heating & A/C self contained unit outside for a mobile home. The old thermostat was a 4 wire system with a green wire on the G terminal, red wire on the RC terminal, blue wire on the Y terminal, and a white wire on the W terminal. The digital thermostat has on the left side G,C,R,W1,Y on the right side L,W2,E,B,O . I tried the green to G, The red to R, the blue to Y and the white to W1. I got no reading on the face. I also tried switching the white wire to W2. Same results. Could anybody tell me what I may be doing wrong ? Any help would be appreciated. Thanks, Defchuck

If the thermostat has a place to put batteries, try putting in known good ones. Otherwise you need fifth wire from the B or C terminal on the system to the B terminal on the thermostat. If you would rather give up the fan only option, than run a new wire, you could move the green wire from G to B at both ends. That would at least confirm the lack of a B connection is the problem.

Do you know that the thermostat you have is set up for a heat pump system, with two stage heat and one stage cooling?

Here is the link to the full instruction manual available directly from Honeywell website:
http://customer.honeywell.com/Techli...0s/69-1037.pdf

You will see that the stat is powered by a 24 volt transformer, so red should be on R, and white should be on C, if green wire is fan then it should go to G, and if blue is the AC compressor then this should go to Y terminal. Looks like the only combination you missed is the white to C.

Review the wiring diagram,and give white on C a try, and you should be OK.

You will see that this stat is very comprehesive, and offers a bit more control than you need, which explains why there are so many terminals.

I kind of had the same problem only I think I had it right. There were only 2 wires coming out of the wall and I put the Red on R and the white on C. Thermostat comes on and works but will not kick the furnace on. Is there some kind of delay built into the thermostat? I didn't really wait very long before putting the old on back on.