Please help... I installed a Hunter Thermostat last winter and heat works fine. Now the AC is not coming on. I think it is the way the thermostat was installed. I threw away the manual and can't figure out the wire connectors. Currently, this is how I have it connected.

Green wire to G
Blue wire to RC
Red wire to RH
White wire to WB
Yellow wire to Y1
YO is not being used.

Heat works but AC is not coming on. If someone knows what I am missing, I would greatly appreciate.

OK not sure why blue is on rc?

Does your ac work off your furnace or separate?

Was the blue on rc before or just on c?

I would say move blue off rc, and push it back in the wall. And put a jumper from rh to rc

JoshDTA... thanks for answering my questions. After seeing so many people complaining about the Hunter, I just took it back to Lowe's and BOUGHT a Honeywell RTH6300B. Just installed it but it is not running. Nothing is running. I am going to spend a little time trying to find out what is wrong.

Honeywell said to use only 5 wires which I do have five wires. Now, the problem is, when I took them off the old White-Rodgers, I forgot to mark which wire is which.

The Honeywell has G, WO/B, Y, R, Rc. I put green wire on G, White wire on W, Yellow wire on Y, Red on R. I do have a blue wire that I put on Rc to check but nothing happen as well as not connecting and put jumper between R and Rc. Still nothing happened. No heat, No AC.

I have a house that has 2 ac and 2 furnace for upstair and downstair. This problem is with the upstair. I think it is a force air furnace with the 2 Fan outside. House is 3 years old. Any idea?

OK lets see. Did you turn the power off the unit before wiring?

If not, and also if you had blue on rc you may have blown the small fuse at the control board. This is a small car type fuse and is in the control board. The control board should be located in the bottom door of your furnace. With the blower. I just got in from outside, need to get a shower I will be back in 15 minutes to help you.

No... did not turn off power.. figuring it was easy as I won't touch anything. I will go to attic and check on furnace to see where and it fuse is blown. Thanks.

Ok... just checked the furnace. The LED lites did not blink like the other furnace. Not sure where the fuse is... I can see the control board but nothing resemble a car fuse.

If there is no car fuse, you may have blown the transormer. The fuse should be pluged directly to the board or it is in line on a wire feeding the board. Not all units have this.

I am hoping that this control board is not expensive if I have to replace the whole board. Just curious though, heat was working earlier before I replaced the thermostat. AC was not but heat works fine until I replaced the thermostat. Did I blown out the control board?

I am looking at the diagram of my furnace. There is a control transformer also on the control board. Is that it?

It could be. If it is not separate. Do you have a volt meter?

My apology to you... I just found the fuse! It is blown. I will go and have it replace and hope that that is all it is. Thanks so much!

Before you change it.

Make sure you have the rh rc jumpered and the blue taped off and not used

Hope that is all it is.

Replaced the broken fuse and I now have cold AC... thanks again so much JoshDTA. You saved me some money. I do really appreciated your help.

Great glad I could help.