Nest thermostat 4 wire honeywell

[Ainsleyjr]

• Hello I am having issues installing the nest thermostat,  I checked the configuration  and it says some wire not detected 

   

  

   

  
  

   

[Patrick_Caezza · Accepted solution]

We need to look at the Furnace/boiler and see where the thermostat wires are connected there.

Post a picture if you can.

[Patrick_Caezza]

It looks like you have a heat-only system.

Try this wiring

Black - B to C

Green - G to G

White - W/AUX to W

Red - R to R (jumper to RC not needed)

When asked during setup in the Home App, select these wires

C, G/G1, W/W1, and R

Do a reset to factory defaults prior to changing the wires

[Ainsleyjr]

yeah it's a heat-only system; I tried what you suggested but it's not detecting the green  and black wire

[EmersonB]

Hey folks,

@Patrick_Caezza thanks for posting and sorry to hear if you're having trouble installing your Nest Thermostat. If possible, can you send us the photo of your wiring setup to your Nest Thermostat. We'll appreciate it if the labels are visible in the photo. Also, make sure that the green wire is properly inserted to the G terminal.

Looking forward to your response.

@Patrick_Caezza I appreciate your response.

Regards,
Emerson

[Patrick_Caezza · Accepted solution]

We need to look at the Furnace/boiler and see where the thermostat wires are connected there.

Post a picture if you can.

[Ainsleyjr · Accepted solution]

Hello Patrick,

yeah you are right i had to look at the wires in the boiler room; it turns out there was only two wire connected to the furnace. The R wire and White wire.

[Patrick_Caezza]

You must have a C wire with a two-wire-only system.

You have the extra wires to create a C wire. Look around your boiler controls and see if there is a C terminal. Many boilers have a 24Vac transformer with a small PCB terminal block.

Something like this.

 There is a good chance the thermostat cable goes there already.

[Jeff]

Hey Ainsleyjr,

I just wanted to follow up to see if you got this sorted out. It looks like Patrick_Caezza has been able to provide a lot of great info here. If you're still looking for some input, just let us know.

Thanks,

Jeff

[Ainsleyjr]

Yeah Patrick_Caezza has been great he pointed me in the right direction 

[Jeff]

Good to hear, Ainsleyjr.

Would you like me to keep this open, or are you confident that you have things resolved from this point? I'm happy to keep this open if you still need more input on this.

Thanks,

Jeff

[Jeff]

Hi all,

As we got our resolution here, I'm going to mark this one as resolved in the next 24 hours. Thanks to all who helped and contributed. If anyone has any other needs, please feel free to let me know before the lock.

Thanks,
Jeff