Nest Learning Thermostat with multi zone heat

[Johnlxii]

Hello, I have a multi-zone heating system with 1 boiler and 3 isolated zone valves (plus 1 for DHW) .  I have a Nest Learning Thermostat on the main zone with remote sensors in the other two zones. I want to eliminate the existing manual dial Thermostats for the 2nd and 3rd zones and use my Nest to control all 3.

It should be able to leverage the remote sensors to energize the zone control valves, but I can't find any information on how to wire the Nest for a second or third zone. 

[Johnlxii]

I am planning to reroute the current wires from the zone valve controls to the Nest in the main part of the house. 

[CoolingWizard]

A Nest can only control a single zone at a time. It cannot be programed to control more than one zone. Each of the remote temperature sensors is a standalone thermostat for that area and zone valve, you would have to replace each of them with its own nest. If you want a nest to control those areas that would mean you would have a total of three nest thermostats...

Ken, The AC Cooling Wizard

[Johnlxii]

Thank you for your response Ken, but I read somewhere that Nest could control up to 3 zones of heat and 2 zones of cooling. I also read it is compatible with zone systems.

Having a separate $300 thermostat to control each zone is not "compatible" with zone systems in my mind.

What makes sense to me is to be able to wire the main thermostat to three zone valves (Yes I would need to run additional wires). The main Thermostat would then use the information from the remote sensors in each of the second and third zones to operate the respective zone valves. 

[CoolingWizard]

Yes you are correct however, you need to consider this as well.  The separate thermostats locations that you currently have are location specific. That is, they are active when the main thermostat calls for heat or cooling.   When Heat or cooling is being called for, those secondary zone thermostats will control the zone controller to activate the zone motor to open or close the supply trunk serving the area. 

Ken, The AC Cooling Wizard

[Jhonleanmel]

Hey folks, 

We appreciate your help here, CoolingWizard.
Johnlxii, 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 concerns or questions from here, as I would be happy to take a closer look and assist you further.

Thanks,
Mel

[Johnlxii]

I'm not so sure anymore.

I had Nest Thermostat and 2 remote sensors in my condo.  It was a single zone, but I could "Prioritize" the temperature in a specific room at a certain time (home office during the day, master bedroom at night).  When I sold the condo. I left the Nest there but took the remote sensors with me.  In my new home (single-family ranch) I have a boiler set up with 4 zones (one for Domestic Hot Water).  Each heating zone is equipped with a taco valve/pump which is wired through a zone control panel.  Each zone was controlled by a 2-wire dial thermostat when i moved in.  I purchased and installed a new Nest Learning Thermostat (Gen 3?) to control the main zone.  I also installed my remote sensors next to the dial t-stats in each of the other 2 zones. 

Currently, I can see the temperatures in each zone, and remotely control the temperature in the main zone.

According to the information on the internet the Nest Learning t-stat "works with multi-zone systems" and "can control 3 zones of heat and 2 zones of cooling".  What I would like to do is run a multi pair T-stat cable from the control panel to my main Nest Thermostat and my hope was that the Nest could in fact control all 3 zones using the remote sensors.  The dial T-stat is simply a 2 wire binary switch... temp goes down, it closes a switch, temp goes up, it opens a switch.  I assumed there were 3 sets of binary switches in the Nest that would do the same thing with some electronic enhancements of course (open and close switches based on the temp at the remote sensor, provide scheduled temp control, etc.).  

I have the first zone connected and working fine.... I just don't know where to connect the wires for zones 2 and 3.

[CoolingWizard]

For your situation, we need to kind of describe the difference between air zones versus the boilers, taco water, temperature sensors, and control valves. What the Nest can do is control a Sigle stage or Dual stage air conditioning, compressor or a one stage or dual-stage gas valve. The Nest thermostat can only be controlled by a single temperature sensor.  That is the sensors inside the display, or a remote nest temperature sensor.  What the single nest cannot do is control multiple air zones.  The Taco valves control independent air zones.  This is why each of those TACO zones had its own thermostat.  

Ken, The AC Cooling Wizard

[Johnlxii]

Thank you for your feedback and patience.  I'm going to see if I can find a Smart T-stat that will control 3 zones with remote sensors.  Maybe Honeywell, or Emerson has a system that'll work.

[CoolingWizard]

Unfortunately, for residential systems, neither Honeywell or Emerson manufacture, or or developed a thermostat that can control multiple water valves with a single thermostat. This is available in commercial systems. However, they’re not adaptable to residential use. This is why your old system had independent thermostats in each of those rooms, and one was considered the master. The master controls the hot water, Combie boiler and then the two additional thermostats controlled the individual rooms to open the TACO valve to allow the hot water to enter the radiators in that room or area. 

with HVAC forced air systems, they could have a zone controller that controls damper valves that can open and close different areas. Each one would have its own thermostat that controls that air zones all thermostats in that case would be the same and would all wire up to the zone controller, which would also be located at the HVAC air handler. Again, one of those thermostats would be wired as the number one or master, and the other two would simply be thermostat to and thermostat three. In this case, all three would be a basic nest thermostat. 

Ken, The AC Cooling Wizard

[Johnlxii]

Got it.  So I'm left with trying to find 3 reasonably prices smart thermostats that will all work off of the same app (like Nest... but cheaper).  Unless I can find 2 additional used Nest e, or Gen 3 units somewhere (2-wire).

You've saved me a lot of unnecessary searching, and I appreciate it.  🙂  Thank you again. 

[CoolingWizard]

The basic nest thermostat operates on two AA batteries and is not a “smart learning thermostat” but you don’t really need that in your case. These things are typically on sale and you can pick up one brand new for about $99.  

Ken, The AC Cooling Wizard

[Johnlxii]

Good to know.  That may be a good option.  Thank you

[Jake]

Hey there,

Thanks for the help Ken.

I wanted to check in and see if you had any further questions from here. Please let me know, as I would be happy to assist, and answer any you may have.

Best regards,
Jake

[EmersonB]

Hi everyone,

@Johnlxii I'm dropping by to ensure that everything is covered here. I hope that the information sheds some light on the issue. If you have other questions and concerns, feel free to let me know.

I appreciate the help, Jake, Mel and Ken. 

Regards,
Emerson

[EmersonB]

Hi Johnlxii,

Just one quick final check in here since activity has slowed down. We'll be locking the thread in the next 24 hours, but if you still need help, I would be happy to keep it open. If there's more we can do, just let me know.
  
Thanks,
Emerson

[Johnlxii]

Hello, I'm sorry for the delayed response.  While I'm disappointed the Nest is advertised as being capable of supporting 3 zones of heat when it does not, I have all of the information necessary to resolve my issue and really appreciate the feedback and information I received from Ken and others.

Thank you

[EmersonB]

Hey Johnlxii,

Thanks for getting back to us. This is not the experience we wanted you to have. Well take note of it and ensure that we'll learn from your experience as we continually improve our products and service. Rest assured that we'll take this as feedback. We'll learn from this to deliver a better process and experience in the future. In case you have any concerns or are still in need of assistance, you know where to find us.

Regards,

Emerson 

[EmersonB]

Hi Rjdequiroz,

We appreciate you taking your time posting here in the community. To properly answer your question, how many Nest Thermostats and zoning systems do you have? Your Nest Thermostat can only follow the set temperature to the Nest Temperature Sensor link to it.

Regards,
Emerson

[EmersonB]

Hey Rjdequiroz,

How's it going with your Nest Thermostat? We would appreciate it if you could share with us the information I'm asking above. So that we could take a closer look and assist you further.

Thanks,
Emerson

[Rjdequiroz]

question. Can the Nest Learning 3rd Gen thermostat take and temperature sensor input from another zone sensor to be the main setpoint to stop/start heating/cooling?

[Johnlxii]

Hello Rjdequiroz, I had a Gen 3 in the living room of our condo with remote sensors in both the master and office and I was able to make any of them the main set-point.  I had the option to pick one in real time, or schedule them for reoccurring times.  It was very handy. 

To be clear, let's say the living room runs 2 degrees warmer than the other rooms, and you set them all to 70 degrees.  If you set the living room as the main set point, that room would maintain 70 degrees, while the other two might be 68.  If you set another room as the main set point, it might be 70, while the living room is 72.

I hope that helps. 

[Jenelyn_O]

Hi there,

I saw your post and wanted to chime in — I'm sorry for the delay. I just want to follow up if you're still encountering the issue. Please let me know as I'll be willing to assist you from here. 

I appreciate your help @CoolingWizard, @Jhonleanmel, @Jake, and @EmersonB.

Best,

Jenelyn

[Jenelyn_O]

Hi there,

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

Best,

Jenelyn

[Jenelyn_O]

Hi there,

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 thread in 24 hours.

Best,

Jenelyn