Opentherm and multi-Zone

[ConorGallagher]

Hi so I have a technical question. Can a heating system be set-up (on an opentherm compatible Combi boiler) to utilise the opentherm communication protocol and still have two zone vales to create multiple zones (upstairs circuit and downstairs circuit) ?

Conor 

[Paul_R]

Hi there @ConorGallagher, thanks for reaching out. You can set multiple zones with an Open Therm system, but for the details of the zoned valves, and how to set them you would need to talk to a heating engineer. What I can tell you, is that you would need a separate thermostat for each zone. Would there be anything else that I can assist you with?

[UanaC]

Hello there! Just checking in, did you see my colleagues previous message?

[ConorGallagher]

Hi folks, cheers for responding I hadn't seen these initially so apologies for the delay. So I am a chartered mechanical engineer, specialising in HVAC. Thus my initial question.

A secondary thermostat isn't an issue, as I had assumed that this would be required. But it's the communication protocol and the interaction of the two smart thermostats to the single combi boiler and the call for heating etc. I'd there a location to get the wiring diagrams within the community? 

Thanks

[AlexD]

Thank you for the information. You can check out our zoned system compatibility guide. As you can see there would need to be a thermostat for reach of the zones. 

As for our compatibility with OpenTherm you can read more information on that in our OpenTherm and what can Nest do with it. You can see that if your boiler has that particular symbol there, it should be compatible. Other may also be compatible but there may be additional hardware required like an e-Bus addaptor. This is for the installer to check and see if possible as we can't advise what may be needed. 

You can also check out our thermostat installation guide. 

As you can see, for OpenTherm you'll need a connection from the Heat Link using the OT1 and OT2 terminals to the OpenTherm terminals on the boiler. 

If you have a zoned system you would need to have zone valves that have connections for the OpenTherm protocol that have that symbol mentioned in the second link to be sure and your boiler will need to have connections for each of those OpenTherm valves. Each Heat Link and thermostat would be connected to their valve and control their zone. 

[LarisaL]

Hi there, just checking in! Did you see the message from my colleague?

[TudorL]

Since we haven't heard from you in a while, I'll close this thread, but if anything comes up, you can always contact our community, as we're a message away. Have a good day and stay safe!