About to have an extension to a kitchen built (_when_ the party wall
agreement finally arrives and is signed.. 6 weeks and counting now,
grrr...) and we're using the disruption and opportunity to change the
ageing combi and put in underfloor heating.
We're looking at a couple of manufacturers products - Hepworth and
Uponor being amongst them, but wondered whether anyone had any
experience of Uponor products, esp their underfloor heating solutions?
In particular, although a lot of information is available for their
systems via the website, one question that isn't answered is which
product to choose - PEX or MLC (multi-layer composite, I think) pipe and
what the relative advantages of each are.
Floor construction is suspended timber - I'll install as much kingspan
(or similar) as will fit between the joists and then fit the heat
spreader plates on top laying the loops in the channels. 18mm ply on
top (_VERY_ carefully screwed into position) and then ceramic/porcelain
tiles on top. The new floor has to be concrete (apparently, to meet
current building regs) but we'll level it to the height of the underside
of the joists so that new joists can be run right across the width of
the room & avoid having to undergo a screed/suspended transition on
every single run of pipe. Area of room is about 25m^2, area of heated
floor will be about 20m^2.
New combi will be Ideal Isar (or Icos, can never remember which is the
The other thing that I'm having difficulty getting to grips with is the
area of heating controls and how the UFH control will interact with the
programmable stat and the combi timer. I had thought that a fully
programmable stat would negate the need for the combi timer, but heating
engineer reckons not.
It would be so much more convenient to be able to control and program
the heating from the hallway rather than having to open the boiler
cupboard, and if a programmable stat capable of multi-zone operation can
also control the UFH then so much the better.
Am I barking up the wrong tree with this?
And another thing... when running with a combi, is a pump needed in the
UFH manifold, and how does this interact with the one in the combi -
will there need to be a 3-way valve so that the floor can be operated
independently of the heating of the rest of the house?
I thought I'd got it, but every time I think about it more questions pop
up... (the Curse of the Software Developer ;-) )