Adding wires for Tstat

[lithiumus]

At the moment, I have 2 NEST thermostats. A 5 wire Tstat wire was installed at both Tstat locations. We realized that the NEST wanted a common to properly charge so a Venstar add a wire was used to provide the common. We also have a dual stage cooling unit (Goodman). How do we get one more wire to the Tstat? Is is possible to use 2 Add a Wire units to get a 5 wire to 7 wire?

[wahoo]

If you are a "pro" then get your post count up and join the pro section. You can ask tech questions there. Otherwise, this is not a DIY site. Sorry

[tedkidd]

If you are a "pro" then get your post count up and join the pro section. You can ask tech questions there. Otherwise, this is not a DIY site. Sorry

Switch to Ecobee, then you only need 4 wires from stat to interface module, which lives at your ahu.

[beenthere]

2 Nest thermostats. Do you have 2 units?

[Shophound]

I thought the Nest stats did not do multi-stage heating or cooling, but just today saw an article about the next gen Nest that does. It's a sweet looking thermostat but strikes me as a little overpriced, when competing stats, while perhaps not as sexy, do almost everything a Nest can do, but cost less.

[mattt787]

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[54regcab]

+1, i didn't think the nest stats were compatible with anything but the most basic systems. Any other thermostat in the Nest price range can easily handle a 2 stage unit.

[jpsmith1cm]

matt787

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[beenthere]

I thought the Nest stats did not do multi-stage heating or cooling, but just today saw an article about the next gen Nest that does. It's a sweet looking thermostat but strikes me as a little overpriced, when competing stats, while perhaps not as sexy, do almost everything a Nest can do, but cost less.

If they add a few more abilities to the Nest, they'll have an Edsel.

[tedkidd]

lmao

(thanks)

[Shophound]

If they add a few more abilities to the Nest, they'll have an Edsel.

Well, at least it does not look like a horse collar!

[Chuck]

If they add a few more abilities to the Nest, they'll have an Edsel.

That's awesome!

[mark beiser]

Assuming you have a 2nd generation Nest thermostat, that is capable of 2 stage cooling and up to 3 stages of heating, they make Add-a-Wire units that add more than one wire.

Until I looked it up today, I didn't realize the 2nd generation Nest was out yet.

It still doesn't have the capability to run both humidification and dehumidification, there is only one terminal for it, so you have to pick the one you want, and it can't do ventilation control.

[lithiumus]

I only had the 1st generation NEST and my contractor asked me how I wanted to hook up my 2 stage Goodman. He said either just hook up stage 1 or combine the 2 stages so it's always running in stage 2. The Tstat wire run is 5 wires but really, we need 7 so that the upstairs NEST can use Rc Rh G Y1 Y2 W1 and C. I'm learning that the NEST is what is termed a "power robbing thermostat" so you really need the C wire to provide a constant charge to it.

I have in-floor radiant heating with 3 zones. I have 2 NESTs for 2 of the zones (the basement zone is not hooked up yet) and the AC is directly connected to the 2nd floor NEST.

I'm considering the 2nd gen NEST but need 7 wires. I had my contractor come back after the initial install to think of a way to get the C wire so he used a Venstar Add-a-Wire. He's not familiar with Add-a-wire units that can add more than one wire. I'm trying to convince my contractor that the ARGO unit he's using needs the Isolation Relay because the NEST is dependant right now on the AC power wires Rc and C for it's power. If I turn off my Spackpak unit, the NEST reports no power at Rh as well. I think I need the Isolation Relay for this to work properly.

Thanks for all the responses!

[toocoolforschool]

Why don't you just use the proper tstat or have the tech run a new wire?

[lithiumus]

I'm planning on getting the proper NEST but running a new wire from the basement to the 2nd floor in a finished house isn't something I want to have done. The Tstat wire were run during the reno when it was just studs and no drywall / paint. I'd rather use a solution like the add-a-wire but to get 2 more wires instead of just one more.

[toocoolforschool]

wireless t-stat?

[lithiumus]

I was thinking to suggest one of these Fast Stat modules...

[beenthere]

Vision Pro HD thermostats, 2 wires. Plus you can use the redlink to access it from the internet.

[tedkidd]

Vision Pro HD thermostats, 2 wires. Plus you can use the redlink to access it from the internet.

Charting?