MVHR, Zones and UFH

[Post and beam]

I had a chat with a prospective builder today and discussed MVHR, UFH and the desirablitity or otherwise of multiple zones for the UFH.

Having read lots of threads on here about not needing zones and the fact that MVHR distributes the air anyway, i had pretty much decided that i wanted a zone for the living room and one for the rest of the ground floor. 2 total.

 

Builder is telling me that you need zones so that the smaller rooms are not overheated by the dominating effect of the large living rooms heat needs.( 6m x 6m)

 

Does not sound correct to me.

 

Help please wise ones.

Regards

keith

 

[Mr Punter]

MVHR is only doing ventilation and has almost no impact on heat distribution, so just look at the UFH.

 

Splitting living and bedrooms into 2 zones is fairly common.  It means you can control the timing and temperature separately by zone.

[Post and beam]

8 minutes ago, Mr Punter said:

Splitting living and bedrooms into 2 zones is fairly common.  It means you can control the timing and temperature separately by zone.

Yes i get that. I only want two zones total and am being advised that i need a zone for every downstairs room.

[JohnMo]

Load of tosh from the builder, you just balance the flows so the rooms don't overheat.  Your idea sounds good.

 

If you have a thick screed, the response time is super slow anyway. Then the thermostat is useless, unless you specify 0.1 hysterisis ones.

[Post and beam]

27 minutes ago, JohnMo said:

unless you specify 0.1 hysterisis ones.

Thank JohnMo, having read so much on here i thought i was on the right track.

With regard to the quote selection above. I asked about high resolution thermostats for my current house when we had a new boiler fitter 2 years ago. I hate the amount of slop, or dead zone, associated with the 1 degree standard ones. I was told such a thing does not exist.

[Iceverge]

1 hour ago, Post and beam said:

Builder is telling me that you need zones so that the smaller rooms are not overheated by the dominating effect of the large living rooms heat needs.( 6m x 6m)

 

 

Sounds like their thinking hasn't been updated since the days of high temp heating with emitters that loose heat to the room quickly and then turn off again. 

 

And in houses with terrible fabric that required constant heating to stay warm. 

 

Low flow temp heating effectively self balances anyway. As the temperature of the room approaches the temperature of the emitter then the energy transfer to the room slows down to almost nothing. 

 

 

 

 

[JohnMo]

57 minutes ago, Post and beam said:

was told such a thing does not exist

 "COMPUTHERM Q7RF."

 

Available from Amazon for about £50

[ProDave]

2 hours ago, Post and beam said:

I hate the amount of slop, or dead zone, associated with the 1 degree standard ones. I was told such a thing does not exist.

I keep on saying it but the proper old fashioned mechanical thermostats when wired properly with a neutral connection for the accelerator heater work damned well.  But it is harder now to find the proper ones. If they don't "click" as you turn them up and down when not connected they are electronic imitations.