Attic Flow and Return.

peter_dublin

Hi All.

Just looking for some advise, about to start plumbing my apartment for rads, two bedrooms, Entrance Hall and Landing, Bathroom and Sitting Room/ Kitchen. All from attic above down through studs, Boiler in Kitchen.

I plan to split it into two zones Kitchen/Sitting Room (40sqm Room, three large windows and fireplace) and the rest as well as a spare zone capped off in the attic possible future conversion. Boiler and valves etc will be located in a hot press which is central in the apartment layout.

What are your recommendations re pipe size, specifically I had planned to one of three possible methods:

1. from the boiler to the attic in 3/4" and drops in 1/2". Three rads on each zone so two runs of 3/4"

2. from the boiler to the zone valves beside it in 3/4" and then flow and return in 1/2"after the zone valves and pipe and drop in 1/2".

3. from the boiler to the zone valve and into a 3/4" to 1/2" manifold and pipe each rad in half inch directly.

My thinking on the half inch is after reading some comments about people using manifolds for the rads and the fact I have been planning to place three manifolds in the attic and then go direct from there to the rads but the differance between this and just piping a flow and return from the zone valve all in half inch seems minimal on such a small system i.e. two zone of 40sqm each and the manifolds seem like overkill as well as the additional cost of materials are a large factor when piping in 3/4" verus 1/2".

Purchased a Ariston Clas HE FF38 which can go as low as 7kw as I below so hence my choice of zones and working from home I would like to be able to heat just the sitting room thanks to the excellient advise of some on here.

Any recommendations would be much appreciated. Heading to Chadwicks Monday :-)

Outkast_IRE

when doing pipedrops to all rads, i would highly reccomend putting in a few automatic air vents , and a few manual ones , above the main drops in the attic.

gdavis

all depends on the length of runs but i would run three quarter from boiler until u have piped second last rad and if run to last rad not too long i would run it in half inch.make sure to run copper from the boiler for a minimum of 1 metre,then u can run qualpex or similar.

gdavis

re outcasts post,i would also strongly recommend putting isolation valve directly below auto air vents as they are notorious for leaking

Outkast_IRE

gdavis wrote: »

re outcasts post,i would also strongly recommend putting isolation valve directly below auto air vents as they are notorious for leaking

Yes the big wide ones with a little black cap are brutal for leaking.

However i dont know how widely availabe they are but there are ones i get they are narrower with a big red cap on top and i havent had one of them leak on me in the 4 years iv been using them.

gdavis

always handy to have a valve anyway imo,for future filling,pressurising,adding inhibitor etc.and i just dont trust the aav's lol

peter_dublin

Thanks, I had planned to fit self bleeding valves to each rad as well as auto air valves to the manifolds if I used them as they would be the highest point in the system and finally if I wasn't using manifold then I was going to put an auto air valve top of the run as it enters the attic.