topic Re: 8 wire Honeywell thermostat in Nest Thermostats

8 wire Honeywell thermostat

jcampagna42 — Sun, 19 Mar 2023 16:10:16 GMT

I have a 10 year old Honeywell unit. If has 8 wires connected. If I understand what I've read, the black (u1) and the brown (also u1) are not used on the Nest. Any help is appreciated.

Re: 8 wire Honeywell thermostat

Patrick_Caezza — Mon, 20 Mar 2023 03:41:49 GMT

@jcampagna42

You are on the correct thought line. Post a picture of the original thermostats wiring and I'll double check for you

Re: 8 wire Honeywell thermostat

jcampagna42 — Mon, 20 Mar 2023 14:39:31 GMT

hope this helps. Had to resize the pic. Will tag you once I figure out how to do that..... 🙂

Re: 8 wire Honeywell thermostat

Patrick_Caezza — Tue, 21 Mar 2023 03:15:18 GMT

@jcampagna42

The U1 terminals control either ventilation or humidifier/dehumidifier. You need to trace the two wires and see where they go.

Re: 8 wire Honeywell thermostat

jcampagna42 — Sat, 25 Mar 2023 16:46:34 GMT

I installed the Nest and didn't use brown and black. It has an orange wire (O/B) that is for the heat pump. I have a basement which is a dual zone with the 1st floor and the upstairs (heat pump thermostat) which is a separate zone. The app tells me that the Nest is incompatible with my system. Does this sound right?

Re: 8 wire Honeywell thermostat

Jake — Wed, 12 Apr 2023 18:28:15 GMT

Hey jcampagna42,

Thanks for the help Patrick_Caezza.

Apologies for the late reply. I wanted to follow up and see if I could be of any help. Please let me know if you are still having any trouble from here, as I would be happy to take a closer look and assist you further.

Best regards,
Jake

Re: 8 wire Honeywell thermostat

EmersonB — Sat, 15 Apr 2023 20:53:01 GMT

Hey everyone,

@jcampagna42, we wanted to follow up and see if you are still in need of any help. Please let us know if you are still having any concerns or questions from here, as we would be happy to take a closer look and assist you further.

I appreciate the help, Jake and Patrick_Caezza.

Best,
Emerson

Re: 8 wire Honeywell thermostat

Jake — Mon, 17 Apr 2023 18:15:18 GMT

Hey there,

I wanted to check in, and let you know that I will be locking the thread in 24 hours.

Best regards,
Jake