Onoff

Don't know. What I can't get my head around with UFH is where it "gets it's cold" from to bring the boiler temp down to something more acceptable to the loop. Or is it that the hot is restricted to that loop by adjusting individually? Do all the loop "returns" just common up?

Thanks all. Back to the main issue as I see it: The boiler is set at 65 deg. As is then the radiators run at 65 deg. If I run that through the coil in the cylinder it'll transfer the heat to the water in the closed system which I assume will get to 65 deg. That's fine to feed the towel rail directly. But the UFH loop? From reading I believe the temperature presented to the UFH loop needs to be in the region 35 to 45 deg? I'm worried if I feed it at 65 it could be detrimental to the slab, tiles etc. So say I fit a manifold, how would that work, one side gets 65 deg and the other goes back to the buffer? I don't get how it reduces the temperature from 65. Cheers

Does the header tank need to be fed a supply via a ball cock like "usual"?

I wonder if it's worth incorporating UFH pipes even if you have nothing to feed them yet...? Cheap and easy to do. Just need to bring the ends of the loop out somewhere convenient.

Ta. I want though the UFH and towel rail at two different temperatures I'm thinking.

Wish I'd thought of that one!

Thinking I can probably adapt the wet tile saw to cut this tile in place... How's the roof / drive going btw?

Maybe add a 2 port valve to stop the UFH loop getting too hot? Have it cutting off via the floor stat?

Cheers. A daft question I'm sure but do I have to have a header tank? Could I maybe treat the water in the cylinder as a semi sealed system, add inhibitor and put an AAV on top of the cylinder? Is there really any need for an expansion pipe? Rough sketch shown less the manifold. As the sketch stands I'm thinking there's an issue as the UFH loop would run too hot i.e. at the temp of normal rads. Appreciate it's bit off the wall.

If only I'd have known... ...I'd still have made my own probably!

You've got to "entertain" something if serious about heating the place properly I'd have thought.

160mm pir insulation I'm guessing minimum?

First I've realised that you've no proper CH! So what you've open fires and electric heaters? Guessing a back boiler and buffer tank?

Me, plan??? Looking at it now. Seriously there's always been an interim plan to tap off the existing antiquated system.

Not yet connected up!