The Efficient Home Forum

Hello! First post!

I'm having a new heating system installed at the moment. The system design is as follows:

2 central heating zones (multiple rads on each)
1 underfloor zone
unvented cylinder

All of the above are connected to the boiler via a low loss header, and each fed by their own pump (i.e. there are no zone valves, the pumps just draw from the header).
A SystemLex wiring centre calls the boiler as required.

I've gone for an Evohome setup, with HR91s on radiators (and a wall stat for the UFH zone). Each pump has its own BDR91. On the advice of the vendor the plumber bought the kit from (I couldn't persuade him to use Evohome shop), we have two controller units.

I'm now trying to work out how to bind 2xBDR91 to each controller to run everything. My ideal world would be

Controller 1: Hot water + UFH
Controller 1: Heating zone 1 + heating zone 2 (each zone pump being called by the HR91s as needed).

I would be super grateful if someone could give me any hints/tips as to how to set this up. At the moment I've successfully got the HW on one controller, and zone 1 on the other controller (both seem to be working correctly), but not sure how to add the second zone etc. (and explain to the controller that the HR91s in zone 2 need to call the BDR91 on the zone 2 pump).

If my 'ideal' setup above isn't workable for Evohome, I guess I would settle for anything that 'works' with the kit I have!

Many thanks in advance for any insights.

James

So the plumber didn't buy the kit from us then you want advice on The EVOHOME Shop forum? Yeah, doesn't quite work like that...

What you are trying to create won't work. Evohome can't section a load of HR91's to one pump and a load HR91's of other to another pump.

I would suggest your plumber sits on Resideo's evohome training or contacts Resideo on 0300 130 1299 and has a chat about the capabilities and limitations of the product.

I know - I'm aiming for goodwill from the community at large! There don't seem to be many specialist Evohome forums out there in general.

I have bought some extra kit (a desk mount/charger) from you if that helps!

If my "option a" won't work, perhaps I can put zone 1 rads plus hot water on one controller, and zone 2 rads on the other controller, and leave the underfloor alone for now (it isn't ready to be connected up for another few months). At the moment I have somehow managed to bind both zones BDR91s to one controller though, so seemingly whenever any HR91 calls, both zones come on. Which isn't a terrible outcome - probably fairly rare I'll only want to call one zone.

Konsta819 wrote:I know - I'm aiming for goodwill from the community at large! There don't seem to be many specialist Evohome forums out there in general.

I have bought some extra kit (a desk mount/charger) from you if that helps!

If my "option a" won't work, perhaps I can put zone 1 rads plus hot water on one controller, and zone 2 rads on the other controller, and leave the underfloor alone for now (it isn't ready to be connected up for another few months). At the moment I have somehow managed to bind both zones BDR91s to one controller though, so seemingly whenever any HR91 calls, both zones come on. Which isn't a terrible outcome - probably fairly rare I'll only want to call one zone.

When you design a heating system with evohome and its a bit 'oddball', you have to design it around evohome, not the other way around otherwise it just won't work correctly. I think you will need 3x evohome Controllers to get this working right with the setup you have and there would be a load of relay work to do as well to prevent back feeds (as you have no zone valves). This type of setup and installation work is for really experienced evohome installers, you won't get a resolve easily here unless they know evohome and heating systems really well.

Try posting here https://www.automatedhome.co.uk/vbullet ... ng-Control