Vaillant wiring conundrum

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Any help on this would be much appreciated.

We are installing the following system:

Vaillant Ecotec Plus 637 system boiler
Vaillant 210 litre indirect Unistor
1 x 2 port valve for cylinder coil
1 x 2 port valve for 2 rads
1 x 2 port valve for Polyplumb UFH manifold
1 x VR10 NTC sensor (cylinder stat)
1 x VR 81/2 Room Stat (Rads)
1 x VRC 470 weather compensator (Programmer)
1 x VR61 wiring centre
And finally 4 x Polyplumb room stats to control each individual zone of the UFH.

Where my problem lies is how do I integrate the Polyplumb UFH controls into the Vaillant Control centre? All Vaillant controls operate only in conjunction with other Vaillant controls on the eBus system and are not condusive to interlocking with 3rd party controls.

Any input or suggestions would be much appreciated.
 
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AFAIK you cant intergrate vaillants controls with other manufacturers, you may have to ditch the vr61 and vaillant controls and use generic controls unless someone knows better ?
 
There will be a way using relays and Tuppa-Centres, but frankly it is easier to do as Picasso suggests.

Unless you use the Vaillant commercial controller.

Which is silly money.
 
Thanks for the replies guys. I make you both right, this is about as far as I got with it too.
It's a consultant who has specified all this and it has somehow fallen upon me to prove to him that it can't be done.
Thanks again.
 
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Ask him to supply you with a wiring diagram and post it here, that should be fun.
 
I have a couple of zones of UFH on zone 2 with Vaillant controls, mine was wired up using a 470F for the radiator zone and a VR81 for the main UFH zone with a Honeywell controller working as effectively a TRV for the small zone in a toilet/utility room. Obviously with this setup the Honeywell controller can not fire up the boiler only the VR81 can for the UFH zone, the UFH timings are set via the 470F I have not found this an issue keeping a stable temperature on both UFH zones.

You would ideally also want a motorised mixer valve connected to the VR61 for the UFH zone, this allows two separate heating curves for weather compensation covering the radiator and UFH zone and the controls also allow parallel charging of the cylinder and running the zone with the mixer valve.

You can assign the 470F or VR81 to any zone if you wish.
 
Thanks Hossacd. The problem is that the UFH covers around 90 square metres and is split into 4 zones which all must be controlled separately under their own stats. I think just using 1 x VR81 to try and gauge the whole area would be a bit of a stretch.

Picasso, Dan. You're not wrong about consultants. They are unfortunately the bain of my life. If I do get any creative wiring diagrams which warrant pointing and laughing at I'll certainly get them posted.
 
Thanks Hossacd. The problem is that the UFH covers around 90 square metres and is split into 4 zones which all must be controlled separately under their own stats. I think just using 1 x VR81 to try and gauge the whole area would be a bit of a stretch.

Picasso, Dan. You're not wrong about consultants. They are unfortunately the bain of my life. If I do get any creative wiring diagrams which warrant pointing and laughing at I'll certainly get them posted.

My main zone is around 100 sq metres with lots of windows which obviously helps as this is always going to cool down before the smaller zone, the initial plan was just to leave the small zone on all the time but it was too hot so they fitted the controller to cap the temperature.

You would be able to control the max temperatures of each zone just not firing the boiler up if it drops, this isn't really an issue I have found as the system keeps the UFH zone running pretty much all the time in the colder months.
 
So the Polyplumb UFH room stats would just open/close the actuators and run the pump on the manifold but not fire the boiler. And the VR81 would just need to be set to a relatively high temperature to essentially keep the boiler firing?

And there would be no need for the UFH controls to have to communicate with the Vaillant controls?

Is this correct?
 
So the Polyplumb UFH room stats would just open/close the actuators and run the pump on the manifold but not fire the boiler. And the VR81 would just need to be set to a relatively high temperature to essentially keep the boiler firing?

And there would be no need for the UFH controls to have to communicate with the Vaillant controls?

Is this correct?

Not quite , on my system the non-Vaillant controls only open/close the actuator for the zone, the zone with the VR81 can fire the boiler and start the pump.

I set the VR81 at a normal temperature and have it in the zone with the most heat loss which means the temperature will drop in this zone first, so when the second zone requires more heat the boiler will nearly always be firing anyway. It is a fairly sizable system as it also runs 22 mainly large radiators so the boiler is running a lot.

With UFH you have a long low burn on the boiler which maintains the temperature of the zone so it very rarely goes off in the winter. You need to time it differently to raditors so you will have it going on a couple of hours before you need the set temp and a couple of hours before you expect the temperature to drop.
 
Sounds a bodge to me.

It is but the only way to get weather compensation, 2 UFH zones and a radiator circuit without forking out for the commercial controls (the boiler was retained when the system was added to so no option to change brand)

Works well which is main thing.
 

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