wiring nest pro edition

[allenfoster]

I have used a Nest learning thermostat on my first floor for several years.  I have 3 zones of forced hot water heat, by oil furnace. No fans, no AC just heat.  I just purchased 2 Nest Pro Edition thermostats, one for the basement and one for the second floor.  The wiring for the thermostats is 24 volt- 2 wires...red & white.  While installing the first one in the basement, the app tells me I need a power connector.  This was supposed to be a simple installation, just as the other Nest was a few years ago.  Why would I need this power connector, that now needs to be ordered?  And, apparently it gets installed in the electrical junction boxes next to the furnace?  Can anybody advise on this?  I am considering returning the 2 thermostats rather than dealing with this.

[Houptee]

The Learning Nest is not supposed to need a C wire in most cases.

Try installing it with just the Rh and W wires and then check power status test .

See if you have Vin 24-30V power shown.

[Zz91xq]

I am having the same issue. Hot water heat, no blowers and 3 zones.  I only have a R and a W wire. I hook them up and I configured the sfwr for Red wire = R  and  W = W1  or W/B.  Both give me the same error code N260.  When I look it up it says that I need to have the power connector.  

[Houptee]

What Nest do you have? The Learning is supposed to work without a C wire.

The Nest mirror glass model and the E both need a C wire.

Can you pull a new wire to the nest from your heating system with 5 wires inside the cable?

If you have a real C common wire you do not need a power adapter.

[EdwardT]

Hi folks,

@Houptee, thanks for the help!

@Zz91xq and allenfoster, how's it going with your Nest Thermostat? Still need our help?

Thanks,

Edward

[EdwardT]

HI folks,

It's me again. I wanted to check back in to see if you have other questions and concerns. Feel free to let me know if you do. 

Thanks,

Edward

[EdwardT]

Hi folks,

I'm just checking in to make sure that you've seen our response. Please let us know if you have any other questions or concerns as I will be locking this in 24 hours.

Thanks,

Edward

[allenfoster]

Edward,

Thank you for your message and support.  It appears that with the thermostats I recently purchased, I need to order and install a power connector for each thermostat.  It looks like I’ll need to access the junction box near the furnace.  I probably have 4 thermostat wires in that box (3 heat zones plus domestic hot water zone).  I have a domestic hot water priority system.  So, I’d have to determine which 2 zones I need to install the connector to and see how to install those connectors.  I am not sure I want to do all this.  I haven’t yet opened those junction boxes but I will take a look when I get a chance.

I am leaning towards returning the thermostats but will make that decision once I look at everything.

I am happy to listen to comments and suggestions.

Thank you,

Allen

[EdwardT]

Hi allenfoster,

Thanks for the update. Nest thermostats are designed to use very little power, and in many cases they can use your system’s heating and cooling wires to get enough consistent power. But sometimes, you may need to connect a common wire (C wire) or power accessory, like the Nest Power Connector, to make your system compatible.

Thanks,

Edward

[EdwardT]

Hi allenfoster,

I wanted to follow up and see if you are still in need of any help. Please let me know if you are still having any trouble from here, as I would be happy to take a closer look and assist you further.

Thanks,

Edward

[EdwardT]

Hi allenfoster,

I'm just checking in to make sure that you've seen our response. Please let us know if you have any other questions or concerns as I will be locking this in 24 hours.

Thanks,

Edward