Nest Compatibility with Hydrostat 3250-plus

[SnackPack]

Hi all,

I am trying to install my nest. I have a oil boiler controlled by a Fuelsmart Hydrostat 3250-plus. I don't see any dedicated "c" terminal for the nest in the unit. My heating system doesn't have any zone control. Would I be able to power the Nest with the "zc" terminal since that is not in use?

Thanks!

[GabrielaG]

Hi SnackPack,

Thanks for reaching out to the community. I understand that you want to check the compatibility of your Fuel Smart Hydrostat 3250-plus with the Nest thermostat because you don't have a C wire terminal. I'm happy to assist you right now.

To get a better understanding of the situation, please help me out by answering the following questions:

• What type of Nest thermostat do you have?
• Can you please send me a picture of your current thermostat wiring?

Any additional details you can provide will be helpful.

Regards,

Gabriela

[SnackPack]

Hi, 

I believe I have a base Nest Thermostat V. 3.

I am sharing an image of the current wiring. The ZC and Zr are currently not in use and I was wondering if I could use the ZC as a common port for my nest as I don't believe the Hydrostat has a dedicated common terminal.

Photograph of wiring 

Wiring Diagram of HydroStat 3250-pro 

Thanks!