Will the Nest Power Converter work with my furnace setup?

[Lclowejd]

I am trying to install 2 Nest Learning Thermostats in my home. I have a dual-zone furnace made by Carrier from the 1980’s. When I installed the thermostats, both showed that they were not receiving enough power (my system does not have C wires).

I am hoping that installing a Nest Power Connector will provide the 2 thermostats with the necessary power, but I can’t find confirmation that a single Power Connector will work in a dual-zone system with 2 thermostats. I’ve attached a photo of the circuit board and one with the terminals in detail. Can someone confirm that the Power Connector will work in my setup, or let me know what, if anything, I can do to get sufficient power to the 2 thermostats?

Thanks!Zoom in on terminalsFull circuit board

[CoolingWizard]

@Lclowejd , if you have dual zones as you say, you will have a Zone Controller with and that is where your thermostat cables will be terminating at.  Then a cable runs from the zone controller to the furnace control board. There is a blue wire attached to the Common so there is Common available in the Zone Controller.  You need to locate the Zone Controller that is at the other end of that cable and where the thermostat cables are at. 

AC Cooling Wizard

[Lclowejd]

I may have have used the wrong technology. We have 2 thermostats (one upstairs and one downstairs) and one furnace. I believe there are dampers that operate to direct the air upstairs or downstairs as needed. I am pretty sure there is only one circuit board. Does that help clarify my setup? Thanks much!

[CoolingWizard]

If you have two separate thermostats and only a single heater, and your zone dampers  then the question  becomes are they manually adjusted or do the dampers have an electric motor? Of they have electric motors, you must have a zone controller. 

AC Cooling Wizard

[Jenelyn_O]

Hi there,

Thanks for reaching out. I'm sorry for the delay. I just want to check if you managed to see the response above. Please let us know if you still have questions or concerns, as we'll be willing to assist you further.

I appreciate your help, @CoolingWizard.

Best,

Jenelyn

[Lclowejd]

Sorry. Thought I already responded. I do have one furnace and 2 thermostats, and I’m pretty sure I have motorized dampers. But the photo I posted shows the entire furnace wiring and I only see one circuit board (also as shown). Could the 2 boards be located somewhere else?  Thanks!

[CoolingWizard · Accepted solution]

@Lclowejd , usually the zone controller is mounted on the outside of the air handler.  If you follow brown thermostat cable, one of them will lead to the zone controller. 

AC Cooling Wizard 

[Lclowejd]

Bingo! I found the 2 boards on the left side outside the air handler. A thousand thanks!

[zoeuvre]

Hi folks,

@Lclowejd, I'm happy to hear that everything has been sorted out. Since we can now consider this one complete, I will be locking this in 24 hours if we don't hear back from you again. Feel free to start a new thread, and we'll be happy to help.
 

Thanks for your help, @CoolingWizard and Jenelyn. 

All the best,

Zoe