topic Re: Compatibility 2 zone Forced Hot water in Nest Thermostats

Compatibility 2 zone Forced Hot water

CT_Homeowner — Sun, 02 Feb 2025 18:30:00 GMT

I have a 2 zone forced hot water (aka hydronic system) with oil fired burner system.

Just installed a 3rd Gen Learning Nest Thermostat in Zone 1 of my house and Nest Thermostat for Zone 2.

Question #1:

Under Nest Thermostat Compatibility/Systems that are incompatible with Nest thermostats, at the bottom it lists "Forced hot water or steam systems" with no further description. Is my system compatible? Here's the link:

Nest thermostat compatibility - Google Nest Help

I installed a Google Nest power connector for Zone 2 as the setup instructed. All seems well there.

I was not prompted to install a power connector for the learning thermostat for Zone 1 but I did have to remove the thermostat and charge the batteries (as prompted) during initial setup. After 1 day, when I go into the settings it indicates "low battery" on the Nest APP. I have it set to display only when touched.

Question 2:

Do I need to install a power connector for my learning nest Zone 1?

Thanks

Re: Compatibility 2 zone Forced Hot water

gmelanymelissa — Thu, 06 Feb 2025 01:00:15 GMT

Hi there!

Thanks for posting here in the community. I understand your inquiries about your Nest thermostat compatibility and the Nest Power Connector for zone 1 (Nest Learning Thermostat). I appreciate the workaround you've already implemented by installing the Nest Power Connector on the Nest Thermostat located in zone 2. I'm happy to help!

Regarding your questions in most cases, Google Nest thermostats can charge their built-in battery using your heating and cooling wires. But there are situations where you may need to connect the Nest Power Connector or a common or C wire to consistently deliver power to your thermostat. To learn more you can see these articles: Zoned system compatibility with Nest thermostats and Nest Power Connector.

However, to determine if your 2 zones forced hot water with oil fired burner system is compatible with the Nest thermostats, I'd like to ask a few questions:

What is the model of your zoned system?
Would you mind sharing a picture of the previous wiring installation and the current on the Nest thermostat?

Once I have these details, I can assist you better with the specific information.

Keep me posted.

Regards,

Melany

Re: Compatibility 2 zone Forced Hot water

CT_Homeowner — Fri, 07 Feb 2025 15:43:35 GMT

Update: The low battery warning (zone 1) went away but I just checked again this AM and it is back. All is well with zone 2.

My zoned system components are as follows:

Viessman Vitorond 100

Fuelsmart Hydrostart

Taco ZVC403 3 zone valve control

The original thermostat for zone 1 (see pic) had white, red and green wires connected to W, R and G.

Nest Zone 1

Re: Compatibility 2 zone Forced Hot water

gmelanymelissa — Sat, 08 Feb 2025 00:22:27 GMT

Hi there!

Thanks for the follow-up information.

The Nest Learning Thermostat 3Gen may have compatibility limitations depending on your specific zoned system. I recommend consulting with a Nest Pro technician. They can accurately determine if the Nest thermostat is compatible with your system and assist with installation if needed.

Let me know if you have any other questions.

Regards,

Melany

Re: Compatibility 2 zone Forced Hot water

CT_Homeowner — Tue, 18 Feb 2025 19:14:55 GMT

After verifying my Nest Learning Thermostat 3G was compatible with a Google Nest Power Connector, I installed one. Everything seems to be fine after 1 week.

I was disappointed that my Nest Learning Thermostat 3G did not detect and prompt me to install a Google Nest Power Connector. My less expensive Nest Thermostat prompted me during installation and paid for the power connector. I had to buy the power connector for the more expensive Nest 3G Learning Thermostat.

The good news is all seem to be working now.