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1

I have an ecobee3 and am looking to switch thermostats to something locally controlled. The two thermostats I've looked at seriously (actually bought them both) are the Zen zigbee thermostat and the Honeywell T6 Pro z-wave thermostat. Based on my current thermostat wiring, I am leaning toward the Honeywell.

My HVAC equipment is: a 2-stage heat-pump with 2-stage heating strips in the furnace/air-handler. As shown below, in the ecobee3, eight conductors are wired to the following terminals Rh, C, G, O/B, Y1, Y2, Aux1/W1, Aux2/W2

cHx97W3
cHx97W3.jpg2146×2862 1.9 MB

For the Honeywell T6, based on the manual, I think my system gets identified as a 3H/2C heat-pump, as shown below.

Dd3pinv

I don't have a heat-pump fault input conductor, so my plan was to wire the Honeywell as indicated below:

e3: Rh  T6: R+Rc
e3: C   T6: C
e3: G   T6: G
e3: O/B T6: O/B
e3: Y1  T6: Y      
e3: Y2  T6: Y2
e3: W1  T6: AUX
e3: W2  T6: E

I wrote to Honeywell tech support and haven't heard back from them. Does this wiring plan seem ok?

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My husband works in a heating and cooling warehouse. I'll forward this on to him and see what his sales guy thinks.

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3

Thank you @april.brandt. That's one more seafood dinner for him. One more hot dog for you :joy::joy: - just kidding!

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4

If you're still on the fence, the GoControl thermostat also supports 3 stage heat pump / 2 stage cooling.

5

Well, I talked to him and he wasn't 100% sure and his sales guys are nowhere to be found. If he sees them tomorrow, he'll ask, but they're like butterflies with ADHD. :grin:

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6

I'm in no rush.

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If you go on the Zen web site, you can plug in the wiring you have and it will give you the proper setup for a Zen Zigbee edition thermostat. Zen Thermostat Installation Guide

Hopefully, this will help a little bit. I have the Zen Zigbee Edition. Overall, I like it quite well but I did end up not using the thermostat scheduler. I think my WiFi network can conflict with the Zigbee mesh (or possibly, one of my neighbors' WiFi setups is doing it). I set up some rules to do the work of the scheduler plus some additional rules to double-check that the changes have been made and if that was not done, go ahead and send the correct settings again. That has worked out well for me to have it set up this way.

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With the Zen, I'll have to install a sequencer-type relay between Aux1 and Aux2, because there aren't sufficient terminals. With the T6 pro, if my proposed wiring works, I wouldn't need to do that.

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He looked at it again. He thought it looked right. The instructions should be clear enough for you to be able to do it. Because of the many different setups out there now, the installers rely almost solely on those instructions. Was there anything else that looked like it "might" work?

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10

Thank you so much! I just wanted a second pair of eyes to go over my planned wiring. Damn A/C system cost an arm and a leg, and I feel better now that someone else has the same thoughts.

Not really. The main thing that worried me was my heat pump doesn't have a fault conductor (L).

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