Continuous pipe system, from boiler for radiators

[andybird]

hello all
oil boiler needs replacing in my dads house he reckons it has to be a special oil boiler as there is no manifold supplying the radiators independently ,ie hot water leaves the boiler passes through 1st rad onto 2nd rad etc .Its a bungalow 50 years old if that makes any difference and surely the last rad on the system would be low output.

and you would not be able to shut down any one of the rads as it would close the system

I expect he is right "he is my dad" but it seems daft
many thanks

 

[CBF]

it's a one pipe system although it's not normally piped like that, normally both ends would be tee'd off of the same pipe & yes you are right the rads get less efficient the further away from the boiler, tbh the way the pipework is done is so out dated it really would benefit from a re-pipe, & personally if i was pricing a new boiler i would refuse to connect it to a one pipe system

 

[Blagard]

Definately time to upgrade. I would concur with CBF. The pipes must be ancient and probably the rads to.

I am not at all convinced the Boiler has to be "special". It is possible that if the boiler also heats the hot water and has a gravity circulation which would mean the boiler would need to be suitable for gravity circulation, which I suppose by todays standards would be special. However it would make more sense to have the hot water converted to a pumped system as it may work out cheaper! - Heaven forbid if the radiator circuit is also gravity!

For what it's worth I worked on a project that used a new one pipe system as little as six years ago. It was actually a composite system where there was a two pipe mains but with rads coming off in groups of up to six piped together as a one pipe system before rejoining the mains.
I recall thinking I wouldn't fancy sitting by the end radiator in the winter! It was a commerial installation in open plan offices so actually not that bad really.

 

[andybird]

thanks for reply

its a pumped system,I cant quite understand why they would plumb a system this way with no way of shutting off each rad individually,for the sake of a few extra lengths of copper pipe.

or is it determine by the boiler that was fitted in these properties many moons ago...

why not even do a ring main and tee off to each rad

the old folks are getting annoyed already as im asking questions...

 

[CBF]

i repiped a system in a house last yr that was exactly like your folks, it was done by her husband donkeys yrs before (he was an engineer), yes as you said that is how a one pipe system was normally piped, no it had nothing to do with the boiler it would have worked better on a modern two pipe system, it doesn't need a "special" boiler however the piping won't comply with the currant part L regs as trv's should be fitted & the system should be changed to fully pumped, some installers may be willing to just do a boiler change however i'm not one of them