SmartThings Community

New Boiler - smartthings control?

(Jamie) #21

I fitted Nest 2 weeks ago and running the unofficial ST/Nest integration. It works great but I only have heating control. It works great via both APPs. I was going to wait for the evohome but cost swayed me to Nest.

(Elliot Richman) #22

It’s been a while now. Any news on when integration goes live?

(Tim) #23

I use a Fibaro dual relay switch for remotely controlling my Combi boiler central heating. There are two contacts R1 and R2 that serve as the connection point for timer, room stat and frost stats. The connections can be configured as mains potential or volt free, I have the latter. One Fibaro relay channel is connected in series with the boiler timer to act as a timer enable/disable. The other relay channel is connected across R1 and R2 and acts as an ad hoc heating demand control. I wanted to retain the original boiler timer as a fall back, in case I lost communication with the ST hub, but allow additional control outside the preset boiler timer events. I can also disable the timer if I am away and don’t want the central heating on. Although the Fibaro is not directly supported, the Zwave multichannel device handler works fine. You might ask why not use the Hub to control times events instead of the boiler timer. One word, reliability! For temperature control, all my radiators have TRVs fitted, apart from the one in the bathroom. Using “It’s too cold”, I set the heating to come on if the temp drops below 10C in the house; a sort of frost stat. I eventually want to use the temp sensor functionality built into the ST motion sensor to act as a room stat. However the system works fine as it is and using the Fibaro saves on expensive dedicated controllers.

(Kaz) #24

If you change boilers - change to boilers ONLY that support OpenTherm - WB/Baxi and a few others does not yet support OpenTherm.

OpenTherm is “boiler remote control” - and gives you much better control over boilers and with Evohome ( you have control of Boiler flame - so boiler temp can be autoset dependent on demand. That can gives savings up to another 15% dependent on Evohome or other control systems.

Bosch is a member of OpenTherm org. but have not yet implemented it in the WB range. I am probably putting in a an InterGas boiler to replace my two Baxi Solo’s in the spring.

(Arnoud) #25

Is this support of the Honeywell devices still coming ‘soon’? It has been over 6 months now…


You can email the UK support team at to be added to our beta.

(Paul Ockenden) #27

And then get an email back saying that the beta is closed and no new applications are being accepted…


Oops! Stay tuned…

(Arnoud) #29

The latest version of the app now allows me to add my Honeywell Round Connect (aka Honeywell Single-zone Thermostat) to SmartThings!

(Paul) #30

Relatively inexpensive option here courtesy of @meavydev

You can pick up this zwave thermostat for less than 50 quid on eBay. I’ve got one running and two more waiting to replace my old Honeywell CM927 wireless stats.


How are you finding it? I’m having a new (Vailant) boiler fitted in two weeks and was going to get a NEST thermostat installed at the same time.
Interested to hear anyones thoughts on Nest as a product and its ST integration.

(Jamie) #32

I personally love my nest thermostats. I have routines to stop the wife over heating the house.

When the motion sensor in the kitchen hits 21 it turns the nest down to 15… Nothing the wife can do to override it until she start to play with SmartThings.

Will it pay for itself, I don’t know but the house never feels too hot or too cold.

(Harrison Hughes ) #33

HOW? I have been trying everything

(Harrison Hughes ) #34

How did you get it connected?

(John Lockwood) #35


In terms of adding Nest to Smartthings as far as I am aware there is still no official integration but for some time there has been a 3rd party smart app. See -

I use this myself and it successfully integrates both my Nest v3 Thermostat and Nest Protect in to Smartthings.

With regards specifically to Valiant. Valiant in the UK do not support OpenTherm which is the open standard supported by Nest, instead they use their own slight variation on the ebus protocol which is not supported by Nest. However it is as far as I am aware still possible to control a Valiant boiler in old style (dumber) on/off control i.e. call for heat and satisfied using a Nest. OpenTherm and ebus both allow the newer smarter ‘modulation’ control method which is supposed to be more efficient than old style on/off control.

Annoyingly in the Netherlands Valiant do sell a module which converts their ebus to OpenTherm and hence would allow using OpenTherm via a Nest v3. If you buy and fit this even though it is their own part and even if you get an official Valiant approved engineer to do so it will invalidate your warranty.

Note: Worcester-Bosch have a similar situation, they also in the UK use ebus and again only in the Netherlands sell an OpenTherm converter module.

Tado an alternative smart thermostat brand supports both ebus and OpenTherm as standard. As far as I am aware they are unique in this. According to Tado ebus is supposed to be a superior protocol. In my opinion the difference is likely to be negligible and I believe relates more to diagnostic reporting and not efficiency.

With regards to having a Smartthings Motion sensor control the Nest Thermostat as described by Jamie I would guess this involves also using Webcore or similar to define an automation rule.

(Harrison Hughes ) #36

Sorry, I mean how to connect the Honeywell single zone thermostat.

(John Lockwood) #37


Sorry I don’t know the answer regarding Honeywell in the UK. It is not helped by them having so many different models.

Consider replacing it with a better supported brand, e.g. Nest, Netatmo or Tado.

(Harrison Hughes ) #38

I would but our Honeywell single zone thermostat is wireless so I’m not sure if I can.


If you live in a cold climate, personally I would never trust smarthings to control a HVAC system without a fool proof backup control system in place.

Imagine you are on vacation, come home to find a frozen mess due burst in a frozen water pipe because of smartthings issue…

(John Lockwood) #40


Typically such wireless thermostats have two parts, a unit which is wired to the boiler and the wireless thermostat which talks to that unit. This is how the Nest works in fact. Nest call their wired in portion the ‘Heat Link’. In some cases the wired in component replaces your existing heating programmer unit.

So, yes it should be possible to replace the Honeywell with a Nest as one possible option.

(Netatmo is similar to Nest in this aspect.)

Tado is a little bit different, they have a Thermostat which can either be purely wireless talking to their ‘Extension’ unit which wires in to the boiler, or the thermostat itself can be wired in to the boiler in which case you don’t need their extension unit.