HI...

I installed the Honeywell RTH221B heat/cool thermostat.

Despite setting the temperature to 65 as the main temp and 65 on all 4 time cyles of the day, the heat goes until I take it off the wall.

I am thinking maybe I installed it incorrectly. I know the guy at the 800 number at Honeywell tried, but its hard for him to know.

The main purpose of putting this thermostat in was to consolidate and older Honeywell Chronotherm that ran the heat and a Honeywell simple dial that was for the AC.

The heat wire has a Green and a White, the red was not used with the chronotherm.

The AC had a white, mint green and red wire. There were all used with the H-dial.

Seeing how it is 30 and snowing here in beautiful New York today... I am happy just to get the heat working correctly and will worry about the AC later.

If someone knows the correct hook-up, I would appreciate it. I have a picture of the thermostat bay, but I don't know how to upload it.



On the left, there is a yellow and green terminal, the right has an Rh, Rc and white.


Thanks... I appreciate any help anyone can lend.

Your problem goes deeper than you think. You will have to sound out every wire and find exactly where they go then wire accordingly or it might be best to call a pro for on site assistance since combining the operation of two different thermostats is not that easy sometimes.

I suppose, and I do need someone in April for the AC yearly. But as far as getting the heat on. I traced the dark green and white wire for the heat back to the zone control valve. Assuming for now I just want to have the heat setting without have to take the thing apart every time to shut it off, what would you do?

Use R or RH and W terminals for heat only on your thermostat.

The green to the Rh and the white to the W seems to be working. I wonder why if red is the universal hot then why the installer (before I lived here) used the green and white.

I cannot answer that question since I did not install it. LOL

At any rate.. thanks. The heat is running... and shutting off too. 25 and snowing in beautiful Westchester County, NY right now.

Stay warm.