Viessmann 200w Weather compensation - underfloor heatg ?

[stanmore]

Hi
I am due to replace a 2.5kw electric underfloor heating system within a suspended timber floor in a conservatory. The conservatory is circa 9 years old with Argon filled double glazed units on two walls and the roof.

Can the Viessmann 200w with weather compenstion be configured to take an additional circuit/zone for a single room underfloor heating system such as a Polypipe single zone unit with room stat, can this be wired back to the boiler even with the weather compensation unit fitted ?

If the Polypipe system is not the right one which is ?

As the conservatory manufacturers had suggested a 2.5kw elect system I imagine that this may have been based upon a heat loss calc, but the underfloor wet system will only produce a fraction of this at circa 70w/m for a in joist system with double spreader plates. I already have a small radiator within the conservatory, which can be isolated can I also link this into the propossed underfloor heating circuit so they can be controlled by one room stat ?

I am lifting the floor as it is a suspended timber floor with 25mm of polystyrene in and is freezing in the winter unless you run the £10 per day electric system. My first step is to install 100mm celotex and then use a wet system with speader plates with plywood and then tiles over the top. Does this sound right ?

any guidance would be very useful or if there is a better way to heat the room with my boiler and weather comp set up I would be very happy to hear about it.

 

[ALEC1]

wood is a great insulator, but everyone will tell you it works..

I regularly install the viessmann ufh mixing valve and it is a great bit of kit, but where the floor is covered in wood the flow temp has to vary between 30 and 55, in screed with tiles or polished concrete the flow temp can be capped at 35c...

If yhe conservatory is old It would be worth putting down a slab and concrete...and avoid wood...

 

[stanmore]

From a quick check on the internet the sub mounting kit is

Viessmann Sub Mounting mixer kit for vitodens 200 up to 35kw. Part no 7439104.
Price: £517.82 + VAT

is this the correct peice of kit ? a little pricey but I presume all i would then need is a manifold, the pipe and spreader plates but even so this is much more expensive than a mixer, manifold and pump set up from the likes of Polypipe and it almosts costs the same !

Are there any other options ?

Do you think if i fit a Polypipe system that this can be linked back to the boiler on a seperate zone as I can't find any info that indicates that this would work with the weather comp fitted ?

If you could recommend a good installer in the South Manchester area to connect up the system and provide the correct details around the system design, as the install of the pipes is straightforward and I hope to do this ?

 

[ALEC1]

the polypipe system cannot be linked back to the boiler with weather compensation...

for various technical reason you do it the viessmann way or no way..

when you order the poly plumb kit don't order actuators or zonal control, the mixing valve or the pump.

I would go for the bronze bodied mixing valve, viessman actuator and a pump....they come in a bit cheaper...

 

[Norcon]

Definition of "conservatory"..

Google wrote

a greenhouse, usually attached to a dwelling, for growing and displaying plants

Why do you want to heat a conservatory in the winter for?
Shut the doors and let the plants use what ever available benefit there is.

 

[stanmore]

Can you help me with the correct kit to order then please

Mixing valve actuator accessory kit,
Part No. 7133 390
consisting of a mixing valve actuator and
supply temperature sensor (strap-on
sensor)

Is this correct ?

I can't appear to find any ref to the bronze bodied mixing valve or which pump I need can you help ?. The floor area of the room is 18m2 and with the double spreader plates this needs circa 80m of 15mm pipe at 225 centres which can hence be laid as one circuit of pipe. As I also hope to run a radiator in the room should I leave this on the normal flow and return or link it into the uf circuit ?

thanks

 

[Norcon]

WC into 18sq/m of greenhouse area with an electronic mixing valve?
Madness.

 

[ALEC1]

radiator should go on the weather compensated radiator circuit...

is the vitodens 200 a wb2, wb2a, wb2b or wb2c....the latter being the current one..

 

[stanmore]

conservatory/green house it's just a description of a room glazed on two sides and the roof with a block insulated external wall on the other, 100m celotex under the floor and argon filled double glazed units set in timber frames. The manufacturers had installed a 2.5kw electric system in a timber suspended floor and that it madness !

We didn't buy it, it came with the property and we are just trying to make the best use of the space. If you have anything constructive to say I would love to hear it !

 

[stanmore]

Alec, thanks for the reply it is the WB2B

 

[ALEC1]

so ts been in several years...and it does have weather compensation...

I think you should ring technical with the boiler serial number, the actuator has been up graded so you need one compatible with the boiler...just to check

7178995 is the actuator
7338214 is the valve
7207285 is the inserts


any pump will do, a 15/50 is about £80 if it is a grundfoss...

 

[Norcon]

the polypipe system cannot be linked back to the boiler with weather compensation...

What would be wrong with supplying polypipes mixer kit with the radiator compensated flow?
Apart from Viessmann losing a sale of course!

 

[ALEC1]

principally because injector valves need a flow at 70c, that and if the controls wont be integrated, so you cold have a situation where by you called for heat with he ufh but the boiler wont know...


With the viessmann kit you can tailor the ufh to the install... for example you can change the max and minmum flow temperature, as well as the rate of change...

 

[Norcon]

principally because injector valves need a flow at 70c

Where do the injector valve maufacturers state that?

so you cold have a situation where by you called for heat with he ufh but the boiler wont know...

So you're saying a demand cannot be made back to the Viessmann boiler from a zone valve?
A boiler thats reputed to be the best in the world and we cannot get it fired up to heat an area of the building. Ooh dear.

 

[ALEC1]

on the last point you are correct, on the first, ask a manufacturer..Thats where I got the information.. I forget from whom... probaby nu heat