Pro Combi 85 HE (Pipework Layout Problem?)

[KeithM]

Looked at a CH system today which has been left half done; plumber did a runner - and after having a good look round think there may be some fixing to do.

There are 22mm F&R pipes branching off to all rads but the downstairs hallway rad completes the 'loop'. 22mm Flow reduces to 15mm and drops down as does the return. Will this create a problem when running the system as the flow will squeeze down to 15mm, through the rad and back up from 15mm to the 22mm return?
All rads have TRV's fitted so I'm thinking if the hallway rad is turned off it will need a bypass fitted somewhere but where? Just before the last rad or near the boiler before any rads?

If anything isn't clear just ask. (It confuses me)

 

[adlplumbing]

if one rads has two locksheild on that the by pass on new boiler not sure on this make think cheep boiler type

 

[KeithM]

if one rads has two locksheild on that the by pass on new boiler not sure on this make think cheep boiler type

Erm, I know you're trying to help but I can't figure out what you're trying to tell me.

 

[kevindgas]

we fit a few 100 HE and if i understand it right
you have a 22mm circuit with a 15mm fed radiator very close to the boiler?

so long as you have a 22mm circuit then the rad can be used with a single turn open on the Lockshield without having an adverse effect on the boiler.

the boiler will cope so long as you have a fully open rad elsewhere (bathroom?)

 

[tamz]

Heating is not done in a loop. The 15mm dropping to the hall rad is the same as any other branch. Look up 2 pipe system.

 

[KeithM]

we fit a few 100 HE and if i understand it right
you have a 22mm circuit with a 15mm fed radiator very close to the boiler?

so long as you have a 22mm circuit then the rad can be used with a single turn open on the Lockshield without having an adverse effect on the boiler.

the boiler will cope so long as you have a fully open rad elsewhere (bathroom?)

Try to bare with me I'm finding it hard to explain via text -

Imagine the flow leaves the boiler on a long straight run, it enters the rad at one side. The return pipe comes out the other side and all the way back to the boiler. In between this rad and the boiler the other rads are tee'd into the flow and return pipes.
Will this work?

 

[matt1e]

Try to bare with me I'm finding it hard to explain via text -

Imagine the flow leaves the boiler on a long straight run, it enters the rad at one side. The return pipe comes out the other side and all the way back to the boiler. In between this rad and the boiler the other rads are tee'd into the flow and return pipes.
Will this work?

Heating is not done in a loop. The 15mm dropping to the hall rad is the same as any other branch. Look up 2 pipe system.

as tamz has said look up 2 pipe system, that's what you have

 

[KeithM]

Think I've got it now, thanks fellas.