I recently installed a new thermostat during the summer. The A/C woked fine. I could not get the heat to come on today. I took the red wire and put it into the Rh and the power for the heat came on. But now the Auto will not work. The heat comes on, but does not stop. When I switch it to "auto" or "fan", the heat comes on. The only way to stop the heat is to turn it off. Now the A/C will not come on. I am sure that I did not wire something right. Can you help?

Check your instruction sheet for wiring. I bet you need a jumper wire from RC/RH. As for the heat not shutting off, is the heat acually on or is the blower motor continuing to run?

Hat solves the no A/c problem. The new theromstat came with a jumper. I took it off. Can I make a small jumper? Second question: the heat is actually on. It blows great. You can hear the switch kick off and the light for the heat goes off when it the desired temp. is reached. The problem is that the heat and blower do not shut off.

Yes, you can make a jumper and put in. Is this electric heat? You say that the heat goes off at desired temp, but it keeps blowing. That tells me that the heat is not on but the blower continues to run, correct? Then most likely the fan relay is stuck or bad. Is your relay in unit or is it in a circuit board? If in circuit board will it remove or is it hard wired?

The heat does not go off. The heat stays on. I can hear the theromstat click when the desired temp is reached, but the heat and blower continue to go. You can see the heat icon disappear when the desired temp is reached, but again, the heat still blows.

And sorry, I forgot, it is not an electircal heat. It is gas heat.

Check your relay. Shut power off to unit and with a screwdriver handle tap it lightly. Turn power on and check. Repeat process again if necessary. If this corrects problem it is only temp. You will still need to replace relay.

Thanks! That worked.

Glad I could help