Dual Zone + weather compensation - possible?!?

My post giving the link is for WEATHER CONTROL WITH MULTIZONE from a WB technical Bulletin.
URL removed picture added.

So I'm assuming it does what it says on the tin. No doubt that it won't be the Full Monty with all desired songs and dances but surely you can hang an UFH area onto an S plan layout.... This diag says you can

 
Sponsored Links
Weather Compensation; automatic variation of the flow temperature according to the outside air temperature.

So, UFH and radiators, two zones, requires two different simultaneous flow temperatures; plus DHW which is either a third simultaneous flow temperature or hot water priority, meaning the heating (one zone at least) goes off for the duration of a HW demand.

That seems to be the question.
 
So, UFH and radiators, two zones, requires two different simultaneous flow temperatures; plus DHW which is either a third simultaneous flow temperature or hot water priority, meaning the heating (one zone at least) goes off for the duration of a HW demand.
From recent looking around I got the impression that all "boiler manufacturer" WC systems seem to implement HW priority otherwise the HW tank cct is to cool. Had not noticed boiler with Simultaneous dual temp flow. Who does that?
 
if it's like vaillants controller and viessman the second zone on the display only activates when the bosch zonal control unit is connected...

there are operational advantages when using boiler manufacturers controls...mixing and matching with other makes is all well and good but there will be a few "rough edges"...

the disadvantage of mixing other makes is that you end up with a littany of controls that don't really talk to each other and offer the customer twice the amount of learning they have to undertake to make there system work..

Hi Alex,sure I take on board what you are saying but I think we are looking at this from different prospectives
What I am saying is that any system can be turned in to a weather compensated system regardless of the whether the boiler in question directly supports it or not
For instance at home I have a Ideal C28 combi fitted, It does not support modulating controls but.......
I have one of these lying around that I may fit if I ever get round to it (doubtful :LOL: )
Add a few mixing valves and sensors which I also have and if I like I could have four floors each with separate compensated flow temps And a ct circuit for hot water
But thing is I got it for free as it came out of a job, you may have noticed the price of it, if I had nigh on £700 to spend I think the C28 would be coming out
And as you say a boiler with better communication fitted
But you can get cheaper stand alone units, for instance in the ops case they could fit the dedicated controller which would compensate the rads flow temp,
The underfloor on the otherhand would just use what ever it needs via the blending valve as it will always be less than the rads anyway
If the desire was to have the ufh truly weather compensated too then the blending valve could be taken out and replaced with a mixer controlled by a separate weather comp controller

Matt
 
Sponsored Links
So, UFH and radiators, two zones, requires two different simultaneous flow temperatures; plus DHW which is either a third simultaneous flow temperature or hot water priority, meaning the heating (one zone at least) goes off for the duration of a HW demand.
From recent looking around I got the impression that all "boiler manufacturer" WC systems seem to implement HW priority otherwise the HW tank cct is to cool. Had not noticed boiler with Simultaneous dual temp flow. Who does that?

Viessmann, ISTR, separate flow & return connections for the CH & HW, with a CH mixing valve set within the boiler.

Most others modulate the burner to give the required (heating) flow temperature (which is usually not hot enough to generate HW).

If you want simultaneous CH & HW (e.g., big HW demand such as a hotel) or multiple independently variable temperature (VT) zones, each zone needs a separate mixing valve & pump. It gets complex and expensive.

Maybe the OP could clarify what he wants.
 
its useful to think mixed and unmixed circuit....with or without a low loss header...

I do tend to look at things like a rather rigid boiler manufacturer, on that I agree...the reason being if I install things as they design it all tends to work rather well...


the wb technical bulletin is a bit lacking....they dont do two port valves in germany!
 
me neither....why would you if you can buy boilers with the valves in side...

The problem is the boiler manufacturers respond to demand, but do nothing to massage it! Naturally installers just keep doing the same old tired stuff they did 40 years ago.


there are real benefits to installing technology as the designers intend in terms of reliability and efficiency...but in the UK we just cant handle the fact that other countries know more than us...and have come up with different solutions and approaches!

Its a scary thought but its cheaper for european manufacturers to develop a boiler for the Uk rather than train installers properly..I refer to worcesters very own greenstar junior and the first viessmann vitodens 100 which won't take compensation controls....
 
its useful to think mixed and unmixed circuit....with or without a low loss header...

Vaillant's 630 and VR 90 controllers seem to be intended to control multiple variable and constant temperature zones.


There's only one catch; they're not available in the UK.

the wb technical bulletin is a bit lacking....they dont do two port valves in germany!

What do the Germans do?
Two-port valves have their place, I'm a bit baffled why the UK seems stuck in the 1960s with 230V AC ON/OFF controls.

Modulating valves seem to have made no impact in the UK, other than as TRVs.
 
the standard answer from the manufacturers is there is no demand...which isn't any surprise as they do nothing to promote the use of modulation valves or controls...

On top of that if the boiler manufacturers develop a boiler for the UK they want to sell that.

Controls manufacturers want to what sells as it is much less effort to sell to someone who knows what they want rather than promote the benefits of different technology.

At the heart of the problem is that the the manufacturers report back to larger multinationals and all they want is good profit...and the better profit is the one that has a lower cost...
 
the vr 90 is a modulating controller...so the un mixed circuits are actually compensated but higher temperature than the mixed circuits...

I install the vaillant stuff as per the instructions...it all works well...

the difference in Europe is that they have constant flow and variable temperature circuits and we have constant temperature and variable flow...

the technology is developed for the former and applied as the latter...hence the lower levels of reliability
 
the vr 90 is a modulating controller...so the un mixed circuits are actually compensated but higher temperature than the mixed circuits......

Boiler reset and system reset respectively, as the Yanks call it. They're years ahead of the UK in many areas as well.

I install the vaillant stuff as per the instructions...it all works well....

Have you installed a VR90 or VRC 630, or seen one in the UK?



the difference in Europe is that they have constant flow and variable temperature circuits and we have constant temperature and variable flow...

Not all of us, but it's not made easy to deviate from the herd.

I believe that with the EU Common Market, you could buy stuff (boilers, controls, cars, sausages, etc) in one EU country and import and use in them in any other EU country, knowing they'd comply with all the local regulations. Is there anything to stop an installer, such as yourself, buying Vaillant, Viessmann, etc., controllers in Germany or France and installing them in the UK? This is assuming you could read the manuals and the controller had an English language setting option.
 
Vaillant's 630 and VR 90 controllers seem to be intended to control multiple variable and constant temperature zones.

There's only one catch; they're not available in the UK.

Shown as UK products in Vaillants Commercial boilers book www.vaillant.co.uk/stepone2/.../commercial-heating-brochure.pdf

Purchase VR90 from http://www.bhl.co.uk/product/VAILLANT_VR90_REMOTE_CONTROL_FOR_GSHP

Purchase VRC630 slightly more challenging and expensive but available from http://www.hawkheatingsupplies.co.uk/Vaillant_Heating_Controls/Management_System/
 
Links in this post may contain affiliate links for which DIYnot may be compensated.
Sorry, think I shall remove my "smart-link" app its just to smart. The dots it puts in the link are ok for me but send a link and it looses its meaning :(

Yes that's the Vaillant book :D

Nice eBay Seller :LOL:
 

DIYnot Local

Staff member

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.


Are you a trade or supplier? You can create your listing free at DIYnot Local

 
Sponsored Links
Back
Top