Looks like this reply got lost in the ether...
Do we really have to though? UFH piping is in contact with concrete floor, so peak temps must be limited, concrete is none too elastic after all. But wood is. And here most of the pipe doesnt touch the studs, so 80C water would give a ballpark about 10C stud temp rise over most of the studs. Where the pipe goes thru the studs near top and bottom, I'll cross my fingers and say it probably doesnt really matter if the last 2" of wood is unstable, as it'll result in close to no overall stud movement anyway.
Reason I'm angling for a full temp circuit is cost and simplicity, if it is doable it would be much preferable.
I was thinking that left hanging loose it would have a lot more drillproofness, it'd just move out the way if drilled. Does it have to be supported over an 8' drop at low pressure?
ohhh, yes :)
I suppose 2 strips of wood glued together would make a more stable upright, arranging the growth rings in opposing directions to counter warping, like pineboard does. Thats quite doable. Add a few screws to back up the glue.
And I guess an easy way to set that is to turn down the LSV until it just gives enough heat on the coldest day. Limited flow rate in the pipe will cap the temp for all but the first bit. Microbore itself would limit flow of course.
Have you got the figures behind that? It wouldnt cause discomfort the way over-warm UFH does.
Partly, yes. Theres no easy way to balance the 2 rooms as there is with separate LSVs if you only use the wall rad. What I had in mind was to use it with a room that would have say 2 rads, and instead we have the heated wall plus one rad in each room. Now the wall contributes a lot of the heat, and the individual rads are used for balancing.
It does of course mean you cant switch one room off and have the other on - well you could hang curtains on it, but you cant do that in any easy neat way.
How much of an issue I guess depends on the house and use patterns. It wouldn't be a probem for the app I have in mind.
I guess the main remaining q in my mind now is whether we can get away with full temp circulating water. I suspect so.
NT