Room thermostats

[CC45]

Hi all,

 

UFH downstairs via manifold.  MVHR going in. House is too big really for the two of us so we are planning on fitting individual room stats so we can run some rooms at lower temps.  I know a few of you have just run the groundfloor off one thermostat.  I'm now looking at upstairs and although the heating requirement isn't great, for reasons of peace and harmony we are planning on fitting some rads - fed from a manifold (possibly a low temp ufh manifold since the rads that look right are well above the heat required) and again I'd like to be able to control them individually off the manifold - so individual room stats due to go in, but where would be the best position for them?  I feel that they need to go towards the external walls rather than close to the door - any thoughts?

 

Thanks for your thoughts.

CC

[Jeremy Harris]

If it were me than I think I'd just fit thermostatic radiator valves.  Simple, cheap and effective.

[Stones]

In our last house we had a low flow temp oversized radiator based system, master thermostat in the hall, thermostatic valves on each radiator. We ran the house with all radiator valves open for an even temperature, but did on occasion turn off the bedroom radiators. Doing so usually resulted in a 1.5C to 2C reduction from the set house temperature.

[ProDave]

The UFH I would always do one thermostat per room, the system lends itself to that perfectly.

 

Room stats upstairs as well would be my choice as you get a setting in proper degrees rather than the usual 1-5 on a TRV. It will also be controlling the temperature at a useful point in the room, not down close to the floor. Though in a well insulated house that won't make much difference.

 

Individual room stats also opens the possibility of programmable thermostats, e.g no point having the bedrooms heated all day when you only want them warm in the evenings to go to bed.

[Nickfromwales]

1 hour ago, ProDave said:

Individual room stats also opens the possibility of programmable thermostats, e.g no point having the bedrooms heated all day when you only want them warm in the evenings to go to bed.

I'd wholeheartedly agree.

I did a similar setup with oversized rads and roomstats per room, with regular lock-shield valves ( so nobody can turn the rad off inadvertently ) all fed off an UFH manifold from a TS. I chose this route for a couple of reasons, but most of all NOT to have the rads fed with uber hot water eg at the set temp of the TS which was in the high 70's, but also as it was a large house with 6 bedrooms which were not always in use. Those rooms were 'mothballed' at 16oC, whereas the rooms in daily use sat around 21oC with a simple rad timeclock and UFH timeclock respective to upstairs and down. 

Programmable room stats are the next upgrade or open source. @DamonHD has a good bit of content / knowledge regarding that as he has developed his own system accordingly, one iirc responds to occupancy too.   

I put the room stats next to each light switch at the same height for aesthetics and it simply leaves a little trial and error to get the temp comfortable. 

These are the touchscreen ones i fitted, but the relay inside is audible when switching so you may want to spend a bit more on ones which switch with solid state rather than electromechanical relays . No complaints from the customer btw, just my observation . 

Fyi you can get a manifold control 'wiring centre', matching manifold actuators and stats all from one supplier. Either Boulder Developments who I buy a lot from or Heatmiser do such complete setups which are plug n play. 

[CC45]

@ProDave and @Nickfromwales, thanks for the info - what you've outlined was exactly the plan I had, I was just having a wobble.  I've spent the day putting the pattress boxes in ready for it all - a surprising number when I've included the electric ufh in the bathrooms and onsuite.  I've got my own spreadsheet to work out heat loss and upstairs it works out at ~ 16w/m2 - the biggest room has a requirement of 500w and I was going to put two 600w & 400h flat panel rads (under the two windows) - producing ~300w each (I could up them to 700 x 400 @ 470w each). I was wondering whether to use ufh manifold - any thoughts?

 

@Nickfromwales - I will get in touch with those two - diolch.  Carmarthen boy here but willing to take advice from a Swansea lad!

 

 

[Jeremy Harris]

500W for a single room seems massive, even for a house that barely meets building regs heat loss requirements. Are you sure that the heat loss calcs are accurate?

As an example our entire 130m² house only needs around that much heat in cool weather, perhaps double that in really cold weather. 

Edited May 28, 2017 by JSHarris

[CC45]

Thats based on a 21deg rise in temp (it will be less than this because no allowance for heat rising up has been included) plus a 25% allowance.  The room has 3 external walls and is ~ 30m2.  I didn't think 16w/m2 was too bad.

[Jeremy Harris]

For comparison, our whole house heating requirement, including the heat gain allowance from appliances and occupants, works out to be about 7W/m² for the same conditions, with the bedroom heating requirements being significantly lower than this (so low that we don't have bedroom heating at all, as the occupants provide more than enough heating).

[Nickfromwales]

12 hours ago, CC45 said:

I will get in touch with those two - diolch.  Carmarthen boy here but willing to take advice from a Swansea lad!

With BD, mention the forum and my username and Byron should give you my 10% discount on top. . 

 

[CC45]

@JSHarris crunched some additional numbers tonight, if I assume average winter temps here, no solar or other gains and no slack then we should get down towards 10 or 11w/m2 or about 2,500 for the whole house.  I'm happy with this. We cannot justify passive standards but we have put more insulation in, an mvhr and put considerable effort into airtightness.  We were going to do solar pv but the drop in tariff put a nail in that coffin.  The rads we do install wont be very big - whether they ever come on or not is debatable but if we eventually sell, then I suspect buyers will expect to see them there. Thanks for your thoughts - something to aim at next time!

[CC45]

@Nickfromwales cheers for that Nick.

[CC45]

Just resurecting a previous thread.  

 

Time to purchase the manifold etc for the radiators upstairs.  So two quotes so far - one using an Emmeti LS radiator manifold and the other using a Disman LS radiator manifold.  Emmeti seems to be a well known brand - has anyone heard of Disman.

 

I noticed that the Wundu ufh manifold has a blending valve that goes from 30 to 70oC - does anyone know of a reason as to why I cannot use one of their ufh manifolds?

 

Any other thoughts on using an ufh manifold?

 

Thanks

 

CC

[Nickfromwales]

I'd unify your equipment and use Wunda throughout. I used to fit B Dev's manifolds with pumped blenders using TMVs, but after reading primarily @JSHarris's feedback their better suited to standard BR builds rather than low energy builds. 

Youll need to get around 45-50oC into a convector radiator to get any useful heat out of it really, ( especially with the small rads your quoting ), so just check what the max setting is on the manifold blender before purchasing. 

Have you considered trench heaters under the bedroom windows instead of obtrusive radiators?

Edited September 16, 2017 by PeterW
Removed the fish....

[CC45]

My wallet started having fits when I looked at the price of those trench heaters.  Her in doors doesnt like then - what a relief.

 

Does any one know if Hep2o pipe will fit into the wunda ufh manifold? Or would you use ufh pipe (with copper connected for the visible sections?).  I think the wunda mixing valve is good for up to 70deg, so it could be a viable option.

 

Hoping Telford cylinder will be sorted this week - I'm hoping to pick them up before the weekend at the latest.  Need to crack on with the heating then.

 

CC

[dpmiller]

Wunda use 16mm I think, so you'd need to change the Eurocones.

[PeterW]

Wunda is 16mm Pert or Pex. They used to do 15mm as an option but I'm not sure they do now. 

[CC45]

So does anyone know of an adaptor from 16mm wunda pipe to 15mm?

 

I assume any wiring centre will work with any manifold actuators and room stats?

 

Cheers

[ProDave]

1 minute ago, CC45 said:

So does anyone know of an adaptor from 16mm wunda pipe to 15mm?

 

I assume any wiring centre will work with any manifold actuators and room stats?

 

Cheers

Travis Perkins sell an adaptor that fits into a 15mm compression fitting and takes 16X2 pipe into it.

 

Pretty much so assuming you are using standard room thermostats. I know at least 1 system where the stats all connect to one common "bus" and that pretty much ties you to using that make of wiring centre.

[CC45]

I was hoping to use the same wunda stats that we have down stairs http://www.wundatrade.co.uk/thermostats/365-touchscreen-thermostat.html and the wunda wiring centre.

 

I will ask at TP.  I can never get any sensible prices from them though.

[Nickfromwales]

Adaptors

[MikeGrahamT21]

The other day I found Pegler Yorkshire Tectite, which is a UK made, 15mm MLCP, can be used with ordinary push fit and compression as long as you use their 3PS liners. Its quite expensive, but for me, worth the extra so it works with lower cost fittings.

[CC45]

I bought the ones Nick linked to - all good.