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zanyzane
Jul 4, 2008, 06:21 AM
Okay I have a mercury thermo that I was trying to replace with a digital Honeywell thermo. I have a Rheem furnace & outside A/C unit. I'm assuming this is a "conventional system"?

The wires don't match up according to the installation manual so this is what I have:

Original Thermo:

Terminals were: B (blue wire), X (brown wire), G (green wire), R (red wire), E (white wire and this continued to the W2 terminal), Y (yellow wire).

Honeywell Thermo: (conventional system diagram)

I'm putting the link to the manual HERE (http://customer.honeywell.com/techlit/pdf/PackedLit/69-1900ES.pdf) and info is on pg 10 & 11.

What it boils down to I have all the wires connected except the B (blue wire) and E (white wire and this continued to the W2 terminal). The diagram shows C terminal accepting C or C1 or X or B wires. I currently have my X (brown wire) there. But I have no clue as to where I should put the other 2 wires.

Well I hope I explained it well enough, and any help is appriciated.

Thanks,

Zane

EDITED
how my old one was connected:

Terminal B - Blue wire
Terminal X - Brown wire
Terminal G - Green wire
Terminal R - Red wire
Terminal E - White wire (jumpered to W2)
Terminal Y - Yellow wire

I put the above to the Honeywell Tstat as follows:

B to Terminal O/B
X to Terminal C
G to Terminal G
R to Terminal R
E to Terminal Y2/E with jumper to Aux/W2
Y to Terminal Y

Now I can make both the heat and AC work by changing the 0170 setup screen to different choices. But I can't find the correct choice to get both heat & AC to work without changing the setting. So either I have it wired wrong or something.

wmproop
Jul 4, 2008, 03:36 PM
For assistance with your Honeywell product, please visit Honeywell |Your Home Expert | Thermostats, Air Cleaners, Humidifiers, Ventilation Sytems, CO Monitoring and Security Systems. - Honeywell Your Home Expert (http://www.honeywell.com/yourhome) or call Honeywell Customer Care toll free at 1-800-468-1502.

zanyzane
Jul 5, 2008, 04:49 AM
For assistance with your Honeywell product, please visit Honeywell |Your Home Expert | Thermostats, Air Cleaners, Humidifiers, Ventilation Sytems, CO Monitoring and Security Systems. - Honeywell Your Home Expert (http://www.honeywell.com/yourhome) or call Honeywell Customer Care toll free at 1-800-468-1502.

Well believe it or not I've already been to the Honeywell site, that's where I got the link to the manual which by the way is the same thing I have in my hands to work with. I also called their 1-800 number. So as a last resort I go on the web and spent 3 hours trying to find other problems like mine, which I did in fact find another post from back in Nov of 2007. The problem was, no one replyed to his post. So I decided to register and post myself. Thanks for the help.

EDITED

After some more reading I found another post that gave a hint about the installation manual of the Rheem unit. I was able to determine it was a 2 stage Heat pump. So then I went to the setup screen function 170 and put in #7 (Multi-stage Heat Pump: Heat pump with backup or auxiliary heating)
After that at function 190 I selected 1 for the Heating Changeover valve, because I had connected a wire labeled "B" to the O/B terminal.

So I had it wired correctly, I just was unsure of the system type. I had tried setting 7 before but it blew out hot air in the cooling setting. But then again I think function 190 was set to 0.

Thanks for the help... perhaps not directly, but I did read a lot of "how to's and posts on this site.

Zane