How big a job is it to implement multiple zones?

[d000hg]

Our new house has a new combi boiler and radiators/CH plumbing from circa 1990 when the previous owners renovated it (Victorian house). They put TRVs on all radiators which is great, but only a single zone for the whole, quite large house (3 reception rooms, 4 bedrooms, loft conversion).

I've already started adjusting the TRVs on the basis some rooms are simply not getting used but would zoning be more effective in reducing our substantial heating costs? Is it a big job requiring re-plumbing, or would all the work be done next to the boiler itself i.e. retrofitting?

 

[oldbuffer]

Have a look at the Honeywell EvoHome system.

If you want to implement multiple zones using normal thermostats and motorised valves, no one can tell you how complicated it is without seeing the existing set up.

It all depends on how the pipes are run. For example, if the flow and return come off the boiler, into the pump and through motorised valves, then if the central heating flow and return already branch after that for upstairs and down stairs its relatively easy. If however (for example) the flow and return service down stairs then go upstairs in a corner, it would be more extensive work.

 

[d000hg]

Yeah fair point. I suppose one would hope it naturally has a few 'loops' one per floor but there's no knowing for sure. It might just be one pipe traipsing around the whole house!

How much difference does zoning make given we already have TRVs?

 

[oldbuffer]

You have a Victorian property. It will have solid brick walls, and unless it has had insulation fitted internally or externally it will leak heat through those walls at quite a high rate. In terms of economics, I suspect you're best bets are:

1. Make sure the loft has the maximum insulation possible (Its either 270mm or 300 mm recommended).
2. Consider double glazing or secondary glazing. Can be an issue if you are in a conservation area. At the very least make sure windows fit well and minimise draughts.
3. Use the existing thermostatic valves to keep little used rooms at low temperatures, but not so low they rob heat from fully heated rooms.
4. If your boiler supports it, consider using weather compensation as an additional level of control.

Whether zoning is worthwhile depends whether the cost and hassle of installing it is outweighed by the benefits. I suspect the benefits would be minimal over correct use of the TRVs.

 

[d000hg]

Cheers for that. Yes absolutely increasing our efficiency in the house is important I was thinking whether zoning might additionally help. For instance heating just the bedroom in the morning, and more rooms at night.

It seems like smart TRVs might be worth looking at as an alternative to zoning though? e.g. if I can tell my existing TRV "be on 2 all day except 6pm-10pm then be on 5". I haven't investigated this much though I see some systems integrate with the boiler/controller... is it worth looking at or a gimmick? Certainly I don't want to be paying per month for it - as a computer nerd I'm wondering if I can rig something up, providing I can buy remote controllable valves/TRVs.

 

[muggles]

A decent smart system such as EvoHome or Genius has been shown to save as much as 30% on energy bills. It's definitely worth doing

 

[Agile]

What do you want to achieve that you are not getting from your existing TRVs?

How thick is your loft insulation?

Tony

 

[d000hg]

What do you want to achieve that you are not getting from your existing TRVs?

I guess the thing is that I want different heating patterns at different times. TRVs are great if there's a room we rarely use - we can manually turn it up in the dining room if we have a dinner party - but less good if in the morning I want only bedroom+bathroom, mid-evening I want living room, night time I want living room+bedroom. Of course I can do this with manual TRVs but only with a lot of running about!

 

[DP]

Second Evohome route. Have installed it a few times and have the system in my house and in son's house. It will do all that you have in mind.

 

[Agile]

but less good if in the morning I want only bedroom+bathroom, mid-evening I want living room, night time I want living room+bedroom. Of course I can do this with manual TRVs but only with a lot of running about!

Generally if you want the heating in a room then you are in that room so turning the TRV should not be a problem.

Also is good exercise!

But if you really wanted to remain sitting and risk lack of exercise medical problems then the Evohome is a very good system.

But it is quite expensive unless you think you really must have it.

I will fit them for others but manage with TRVs at my home! Need the exercise!

Tony

 

[d000hg]

Second Evohome route. Have installed it a few times and have the system in my house and in son's house. It will do all that you have in mind.

A quick look sounds promising - a few quick queries if I may (tell me if I should contact them directly):

1. the individual valve controllers aren't WiFi but talk to a central controller, which IS WiFi?
2. Now presumably this will work regardless if I have one or multiple physical zones, for its smart-zoning? But multiple physical zones might allow it to do so more efficiently since sending hot water round the entire house to heat a single room?
3. I can have up to 12 smart zones as standard, typically equating to one per room... but I can have more than 12 valve controllers? e.g. my living room might have two radiators and I might e.g. have 11 rooms but 20 radiators in total.

Out of interest, are there more DIY systems out there for the nerds? For instance I can envisage those into Raspberry Pi putting their own system together if they can simply buy controllable TRVs and a way to talk to them. Are there any open systems or are they all private protocols?

 

[Agile]

Each rad unit communicates by wireless to the controller.

The controller is connected to you WiFi and you can use your phone to program the controller.

The controller has a maximum of 12 rad channels then I think you might be able to add a second controller to control another batch of 12 rads but their web site is surprisingly silent on this topic and their telephone line is jammed and not accepting new calls!

 

[Pin 5]

12 zones not radiators. You can have 10 radiators in one zone if you like.

You could have 20 rads, split over 2 zones 10 radiators per zone.

 

[d000hg]

That's what I was hoping Pin5. I wonder if you have to buy their fancy control screen unit... or can just do it all by phone/computer? I can see this being an expensive system if you want the bells and whistles.

 

[Pin 5]

You need the base station as that "speaks" to the hr92s.