Nest zones with system boiler

techno79

Established Member
Joined
Mar 18, 2007
Messages
340
Reaction score
11
Points
136
Location
London, UK
If my house has a single system boiler to heat the whole house, is there anyway to create different zones that can be controlled? My thinking is some smart thermostat valves for the radiators? I'm not really sure but just thinking of the idea.
 
If cutting up/re-running the pipework to add zone valves, or re-wiring to allow electro-thermal actuators you be fitted to your radiator TRV bodies then a wireless system, like Honeywell Evo, is the only realistic option. Note you really need an integrated system that has all the component parts for it to work effectively - reliable and accurate room temperature measurement options, actuators to fit your radiator valve bodies (or suitable adapters), and proper demand feedback to your heating zone valve/boiler. Maybe hot water control too if you don’t have a combi boiler.

It can be possible to find methods to allow cross-system integration, but then you are reliant on another gateway (or maybe several) to tie it all together and make it work. If these use cloud-based layers then you have many potential points of failure that can stop the system working, and may be quite complicated to set up and maintain. For this reasons I generally recommend the system approach rather than mixing and matching different controls hardware.
 
Have a look at Honeywell EvoHome

I had a look at a YouTube review of this system and I really like it. It was a 2 year old video so just wanted to know if there were any newer alternatives to this that were worth considering.

My house will be having a system boiler (most likely Vaillant) and a Megaflo storage tank.

Does the Honeywell EvoHome TRV work with all types of radiators or just a specific subset? I'd be looking to get new radiator installed so I have the flexibility to get something that will be a more modern design but also ensuring it is compatible.
 
It works with all radiators but its best if your plumber installs Honeywell valve bodies. As for alternatives, I know Valiant have something similar but not to the EvoHome standard. I also know that EvoHome have just had an Opentherm Upgrade as well. I think that this is still one of the best systems on the market for flexibility and control - 12 independent zones.
 
What about a hive theromstat and then hive trvs for each room / zone that you want to regulate?

In the majority of cases hive trvs can be added to existing rad valves so no plumbing required.

Hive is usually a doddle to install as well so can give it a go yourself if you’re feeling brave!
 
Have a look at EvoHome reviews then have a look at Hive TRV reviews then decide for yourself. As you note EvoHome has been around for 4 years or more with consistently solid reviews.
 
Evo is based on a product range that Honeywell has been producing and refining for approx 20 years now (it is based on, and still remains compatible with, elements of the Hometronic system). The current range of radiator controllers are their 3rd generation. The system is therefore very mature and has had a lot of specialist development to refine its core control strategy over this time. It may not have cutting edge industrial design ir receive constant firmware updates, but in terms of its levels of control and range/flexibility it remains one of the leaders in this market.
 
If cutting up/re-running the pipework to add zone valves, or re-wiring to allow electro-thermal actuators you be fitted to your radiator TRV bodies then a wireless system, like Honeywell Evo, is the only realistic option. Note you really need an integrated system that has all the component parts for it to work effectively - reliable and accurate room temperature measurement options, actuators to fit your radiator valve bodies (or suitable adapters), and proper demand feedback to your heating zone valve/boiler. Maybe hot water control too if you don’t have a combi boiler.

It can be possible to find methods to allow cross-system integration, but then you are reliant on another gateway (or maybe several) to tie it all together and make it work. If these use cloud-based layers then you have many potential points of failure that can stop the system working, and may be quite complicated to set up and maintain. For this reasons I generally recommend the system approach rather than mixing and matching different controls hardware.

What would you recommend then for 2 zone system set-up? We have 3 storey town house (approx 10yrs old) with old style thermostat in hallway and another on top floor.

was thinking of Nest thermostat but guess I’ll need x2?

we are having an Ideal Vogue fitted in next few weeks so was thinking of doing it all together
 
If all you want is to keep your existing two zone system and don’t think you might want full room zoning in future then any of the smart stat systems would work. If you want sime wire-in replacements for your existing thermostats to keep wiring simple (and with devices that do not look to industrial on the wall) then Nest & Nest-E or Heatmiser Neo (with a Neo Hub) would be good places to start.

Who will be doing the controls install? If it is the heating contractor then you need to speak to them first. I’d be wary of just handing them over a set of unfamiliar controls and expect them to fit it for you if they have no experience. While all these systems are very simple to fit/wire electrically you may find some resistance from installers who have yet to embrace smart heating controls.
 
What would you recommend then for 2 zone system set-up? We have 3 storey town house (approx 10yrs old) with old style thermostat in hallway and another on top floor.

was thinking of Nest thermostat but guess I’ll need x2?

we are having an Ideal Vogue fitted in next few weeks so was thinking of doing it all together
What controls do you have now? Not those awful danfoss ones? (I only ask as they seem to be fitted with ideal boilers on new estates)

Get yourself 2 x wired hive stats that way you can use the existing wiring (only 2 are needed plus neutral iirc)

Plug the hub in and you’ll be ready to go in an hour
 
If all you want is to keep your existing two zone system and don’t think you might want full room zoning in future then any of the smart stat systems would work. If you want sime wire-in replacements for your existing thermostats to keep wiring simple (and with devices that do not look to industrial on the wall) then Nest & Nest-E or Heatmiser Neo (with a Neo Hub) would be good places to start.

Who will be doing the controls install? If it is the heating contractor then you need to speak to them first. I’d be wary of just handing them over a set of unfamiliar controls and expect them to fit it for you if they have no experience. While all these systems are very simple to fit/wire electrically you may find some resistance from installers who have yet to embrace smart heating controls.

thanks guys - our heating engineer actually recommended hive so I’ll have a look at those. It would be him fitting them as I’m like kenny Everett when it comes to all things DIY
 
thanks guys - our heating engineer actually recommended hive so I’ll have a look at those. It would be him fitting them as I’m like kenny Everett when it comes to all things DIY
 
thanks guys - our heating engineer actually recommended hive so I’ll have a look at those. It would be him fitting them as I’m like kenny Everett when it comes to all things DIY

If you are happy with the Hive app and functionality then I’d stick with what he knows. Being a guinea pig for him to supply & install an unfamiliar system is not the best idea!

In reality there is not likely to be much difference between any of the smart stat type products in this application, they will all work in a similar way with similar results.
 
From what I read, the Honeywell Evohome supports 12 zones. Each zone can have multiple TRV sensors. Does this mean it can support more than 12 TRVs? Or is there a 12 TRV limit as well as a 12 zone limit?
 
From what I read, the Honeywell Evohome supports 12 zones. Each zone can have multiple TRV sensors. Does this mean it can support more than 12 TRVs? Or is there a 12 TRV limit as well as a 12 zone limit?

You can have as many TRVs in a zone as you like - either a a single group all working to a “master” room sensor reading but sharing a common setpoint, or as a “zone of many rooms” where the radiator controllers all use their own local sensor but all still share the common setpoint.

So it’s a 12 zone limit, not a 12 room or 12 radiator limit, accepting that a large group of radiators in a single zone prevents individual control.

In larger houses many customers simply run two (or more) Evo controllers so that they still retain “per room” feedback and control. The maximum number of zones in a single property I’ve worked on to date had over 180 separate zones, all controlled using Evo manifold controllers (most zones were wet or electric UFH, with each zone including floor and air temperature control, plus zones for towel rails and other forms of supplementary heating). The Honeywell system dealt with all the room-side heating controls, but there was also a huge amount of complex main plant (multiple boilers, combined heat and power engine, several main pumpsets), ground source heat pump system for chilled water for cooling, proper air conditioning with central AHUs and reheat terminals, swimming pool etc which required sophisticated BMS controls and commercial style control panels too. But the Honeywell system works brilliantly within the mix and is much easier to operate and maintain by the on-site maintenance team compared to a full BMS system. And the Evo systems just go about their business giving excellent temperature control without the need for any custom programming or complication, and was installed and commissioned with the minimum of fuss! It’s not common to have houses with quite this scale or complexity, but I’ve generally had one or two like this a year for the last several years and many, many more with 30-50 heating zones.
 

The latest video from AVForums

TV Buying Guide - Which TV Is Best For You?
Subscribe to our YouTube channel
Back
Top Bottom