UFH from existing radiators?

[Marko]

I have a very, very small bathroom with an existing rad in it. I'm going to be ripping the bathroom out soon and wondering if it's possible to connect the UFH flow and return to the existing pipes; or, is that too simple and I'd need a proper manifold setup?

[JohnMo]

I really wouldn't bother. You need UFH flow way lower than radiators. Plus plenty of insulation under it, otherwise it's pretty rubbish. If you want to take the chill off the floor use an electric heating mat under the tiles. And then just fire up as you need it on a run down timer so you cannot leave on for weeks.

[Marko]

1 hour ago, JohnMo said:

I really wouldn't bother. You need UFH flow way lower than radiators. Plus plenty of insulation under it, otherwise it's pretty rubbish. If you want to take the chill off the floor use an electric heating mat under the tiles. And then just fire up as you need it on a run down timer so you cannot leave on for weeks.

Thanks. I should have really mentioned that I’m running an ASHP so temps are pretty low - mid 30’s.

Edited May 5, 2024 by Marko

[Nickfromwales]

9 hours ago, Marko said:

Thanks. I should have really mentioned that I’m running an ASHP so temps are pretty low - mid 30’s.

The issue is about zone control then, as the flow temp may be "OK". How do you propose to control the heat input and floor temp? Do you have UFH anywhere else in the dwelling?

[Super_Paulie]

Snake the return up and down under the floor from the rad and use a trv to control the floor temp? Cost you nowt.