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Nest, dual zone trol-a-matic

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01-17-16, 09:28 AM

82caddy

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Nest, dual zone trol-a-matic

Hi All,

Looking to upgrade to new thermostats in my home that was built in 91. Have a dual zone dampener system by Trol-a-Matic with two thermostats.

Currently have a Honeywell RTHL2310B in the basement wired as such:

In the upstairs there is an old round dial mechanical thermostat wired like this:

The trol-a-matic is wired this way:

My wife would like two nest thermostats installed. Is this possible?

Thanks!

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01-17-16, 02:06 PM

PJmax

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Welcome to the forums.

I don't believe you can connect two nests to the Trolatemp board. I'm pretty sure you'd need to upgrade to something like the Honeywell HZ311 - three zone controller.

Is this a heat pump system and if yes.... is there back up electric heat ?
The HZ311 is not used for a heat pump.... you'd need a HZ322 instead.

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