Combi CH Pipework Layout

[morg]

Hi, Could do with some guidance if anyone is able to help please!

I am planning on installing the rads & pipework myself (to save on some costs) - Property is a chalet bungalow.

I've done a few diagrams but this one seems to make sense (but not sure if correct).

Followed some websites guidance with the reverse return method to make all circuits similar resistance.

Intended combi boiler would be 30kW
Flow and return pipes would be 22mm (pb plastic)
drops/pipework to rads 15mm (pb plastic / copper)
all 8 rads total about 8kW (5-6 rads on TRV's)

1 zone system for both ground floor and 1st floor (orange rads are ground floor, big greens are first floor bedrooms, little green is 1st floor bathroom).

Would this be the correct way to go about it? As this plan avoids the need to plumb pipes through joists (joists are running left to right), so most of the pipework is running above joists along the internal side of the eaves (i.e. service void or back of dwarf wall)

Thanks for any help

attached a blank plan if you have any better suggestions cheers

 

[cross thread]

That’s a one pipe system ,look up two pipe.with such a low kw requirement make sure your choice of boiler will rate down to your requirements.

 

[morg]

Thanks for the help,

I got it all wrong then

Definitely don't want a one pipe system.

Would this be a better layout?

I am planning on 1 x mixer shower, so 30kW boiler seemed about right (main eco compact combi 30kW) looks a good boiler for the price. But I seem what you mean, could be best going with the 25kW version?

Cheers

 

[morg]

Hi,
I've been looking and the first diagram I posted was drawn out to be a reverse return system (with Trvs and lockshields on every radiator)

It doesn't appear to be a one pipe system??

 

[cross thread]

Get a combi that can be rated down to the heating output you require,

 

[morg]

Will do thanks

I think I would like to go for the reverse return method,

Would the following (original post) with TRV's/Lockshields be a two-pipe system with reverse return or is it a one-pipe system as mentioned?

 

[Iddy]

Yes, that's a 2 pipe system with reverse return
You don't want TRVs on every rad - where you have your room thermostat (normally the hallway), you would put 2 lockshields - the thermostat controls the temp in that area so no need for a TRV on the rad.

 

[Iddy]

And as mentioned above, you'll benefit from a boiler that can modulate down to a low output for heating. E.g. the Vokera Vibe max 26c can modulate down to 3kw

 

[morg]

Thank you for confirming it is a 2-pipe system

Yes 2 lockshields on the room with thermostat, which is probably going to be the living room rad. Hallway has vaulted ceiling so I'm not sure if it would work well there

That Vokera Vibe max 26c boiler looks good and around the same budget so yes I will go for that one thanks

Thanks again much appreciated