[JohnHemingway]

I'm switching my old stat to a new one that lets me enter a program.

I have an electric central air furnace and a thermopump outside that provides heat and AC.

I'm going from a honeywell CT3600 or so (looks the same as in the manual for that one but without the program buttons) to a RTH8500.

I have 6 wires coming out of the wall and here are how they were plugged:

Green - G
Red - R
Blue - C
Orange - O/B
Yellow - W1 and jumped to Y1
White - W2 and jumped to E

My question is that on the old stat W1 is jumped with Y1 and W2 is jumped with E which means that according to the new stat I would be putting both the yellow (W1 and Y1) and the orange (O/B) in the same terminal.

How should I wire it and where should I put jumpers?

[hvacservicetech_07]

Are the terminals on the new thermostat the same?

[JohnHemingway]

The new stat has one terminal that is W and O/B with W being the conventional and O/B on the heatpump side

[hvacservicetech_07]

Just w, no w2?

[hvacservicetech_07]

Green wire-G
White wire- w with a jumper to E
Yellow-y
Orange-o/b
Blue-C (common)
Red-R

[JohnHemingway]

Yew the terminal is marked W on the conventional side and O/B on the heat pump side. W2 for the conventional is on the aux terminal for the heat pump.

http://hvactroubleshooters.com/HONEY...%20INSTALL.pdf

On page 10 there is a nice diagram of how the new base's terminals look like

[hvacservicetech_07]

Ok, the W terminal is also O/B (reversing valve). You're orange wire will go on that terminal,you can jumper y and w if you want. Wire it the way I listed above. Also jumper w2 and E together.

[JohnHemingway]

So that means I will have the following

R - red
C - blue
G - green
W, O/B - white with a jumper to E
Orange
Y - yellow

I can jump Y and W which means on the W, O/B terminal I would end up with white, orange and yellow all being jumped with Y and E

[hvacservicetech_07]

No, the jumper goes between w and y, w2 and E. White wire will go to w2 and yellow to y, orange to w..

[hvacservicetech_07]

Blue-C
Yellow-y with jumper to w
Orange-W
White-W2 with jumper to E
Red-R
Green-G

[JohnHemingway]

Final result would be (making sure I understand before I blow the new stat):

G, R, C in their respective terminals
White wire - E jumped to the aux, W2 terminal
Orange and yellow wires to the Y jumped to the W, O/B terminal

[hvacservicetech_07]

Correct. Be sure to shut the power off to the system and double check you're work before restoring the power.

[hvacservicetech_07]

That thermostat may require an installer setup,should be instructions in the book.

[hvacservicetech_07]

Post back and let me know that everything worked OK, or if you have any problems.

[JohnHemingway]

Heatpump switched on but it feels pretty cold. Letting it run to see if it's AC or heat.

On the old stat I would have to switch between heat for the heatpump and emergency heat for the furnace depending on how cold it was outside. Now the new stat list the available systems and I only have heat and AC as options. Will the new stat know when to switch to the furnace?

[hvacservicetech_07]

You will need to set that up. This stat can be used as an heat pump or conventional, you are probably just running straight a/c right now.

[hvacservicetech_07]

Go into the installer setup and select you're system type.

[JohnHemingway]

Looking at the list of options on page 18 of: http://hvactroubleshooters.com/HONEY...%20INSTALL.pdf

I chose option 9 for my system which includes a furnace inside and a heatpump that can also do AC outside

[JohnHemingway]

If I should chose option 7 then when it asks me whether I have a heating or cooling changeover valve which do I enter? Try one and if it's blowing AC chose the other?

[hvacservicetech_07]

Yes, you have a reversing valve.