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akg4y 04-13-2010 09:15 PM

Thermostat Heat Pump Wiring difficulties
My brother in law has a Honeywell thermostat connected to a Heat pump. The thermostat was model T8411R with this installation manual:

There wiring was as such on the Honeywell:
G- Green
C- Black
R- Red
Y & W1 (jumpered)- Yellow
L- Blue
W2 & E (jumpered) - White
B - Empty
O - Orange

On the new thermostat
I connected:
(New thermostat manual)
Green - G
Black - Ts/C
Red - RH/RC jumpered
Yellow - Y1
White - W1
Orange - O
Blue - Not connected

The heat does not seem to be coming on and I am wondering if that is because I should be connecting Y/W1 jumpered together and have white go elsewhere? The installation manual for the new thermostat says W2 should not be used for a heat pump so that's why I did it the way I did but seems like its not right. Any ideas?

wirenut1110 04-14-2010 04:49 AM

Looking at the diagram, there should be a jumper between Y and W1, and your auxiliary heat goes on W2.

You'd be using W2 for your auxiliary heat not the heat pump per se.

beenthere 04-14-2010 05:51 AM

I don't see a terminal marked Ts/C on that diagram. And the side note says DO NOT connect a common wire to it.

According to the Control 4 diagram, you don't need a jumper from Y1 to W1.

Is it only the heat that doesn't work. Or is it that nothing works.

The TH8411R was told weather to energize the RV in heat or cool. Your new thermostat uses O to energize in cooling, and B to energize in heating.
If your outdoor unit is a Rheem/Rudd unit. You need to use the B terminal, instead of the O.

wirenut1110 04-14-2010 06:08 AM

Oops, sorry, I was looking at the old t-stat manual, not the new one.

akg4y 04-14-2010 12:45 PM

Sorry looks like I may have linked to an older version of the control4 thermostat, Im working on finding a digital copy of the new one, but essentially one of the TS connections on the thermostat is now called TS/C and is recommended for use with a common wire which is what I did. The rest of the connections seem the same but Ill post the link to the new manual once I find it.

With regards to function, the AC is working fine and turns on automatically, and I can turn the fan on and off via the thermostat with no problem, the only thing that doesnt seem to be working is getting the heat to kick on. The temperature in the room when I tried was about 80 degrees and I set the thermostat to 86 and waited 2-3 minutes with nothing happening.

Thanks for your help. Beenthere, the will the outdoor unit say if it is Rheem/Rudd on it (sorry not sure how to figure that out)? Also please excuse my ignorance but what is RV, the heat changeover valve? If the new thermostat uses O for cool and B for heat Im a bit confused as to what wire would connect to B since right now nothing is connected. The only wire I didnt connect that was previously connected was the blue wire which I believe is just a status wire and has no use with the new thermostat. There is a brown wire that was not connected to the original thermostat which I left unconnected.

akg4y 04-14-2010 02:01 PM

Ok, here is the correct intallation manual for the new thermostat.

beenthere 04-14-2010 02:43 PM

It will have a label somewhere on it sayings brand name.

On the old thermostat. You used the O terminal for both O and B.
On your new thermostat, you use the individual O or B terminal. So if your outdoor unit is a Rheem/Rudd. You hook the orange wire that now goes to the O terminal, to the B terminal instead.

Since it works in cooling. That shouldn't be the problem. But check just in case.

What does happen when you try to run it in heat mode.

PS: That thermostat may have a 5 minute delay built into it. Meaning that you will have to wait 5 minutes before it will bring on the heat or A/C. After it runs the unit.

akg4y 04-14-2010 09:26 PM

Is there any risk in trying to change the wire to B from O without knowing what the unit is?

When I turn on the heat nothing happens, the fan doesnt turn on and if I turn the fan to 'on' instead of auto the fan runs but room temperature air blows. I may have to test it with waiting more than 5 minutes though because I only waited 2-3 min when I did it last time.

beenthere 04-15-2010 05:16 AM

If nothing happened. Changing the wire from O to B won't help any.

Retest it, and wait the 5 minutes to see if the heat runs.

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