Single Pipe CH System

[dB]

I am replacing an 15yr old + boiler and have a single pipe CH system. I also wish to add 3 x rads to converted attic.

Should my single pipe system be replaced with 2 x pipe system?

Also which boiler......

Any advice would be a start...

dB

 

[sterose]

I would really like to know how a 1 pipe CH system works.
Are you sure you are not mistaken?

 

[dB]

The inlet feed to each radiator is fed from CH pipe and outlet from each radiator feeds back into same CH pipe. CH pipe returns to boiler after feeding existing 7 x radiators.

Does this make sense?

(Maybe I've got it all wrong....)

dB

 

[AdeyB]

No you haven't got it wrong...

One Pipe System Hot water is pumped through a single pipe underneath all the radiators, then back to the boiler for re-heating. Hot water (lighter) rises into each radiator at one side of the radiator and the cooler (heavier) water falls back into the single pipe on the opposite side of the radiator. The last radiator is always cooler as the water has already given out most of its heat in the rest of the radiators



These systems were popular 30 years ago and a lot of them are still working. There is no restriction to the number of radiators, so they are ideal for industrial use, but all modern domestic systems use two pipes

 

[oilman]

If it works ok, keep it as a one pipe system. They were the replacement for steam heating systems when heating went over to water. Two pipe systems wouldn't have sold against one pipe steam systems, and in those days it was almost all gravity systems with big (expensive) pipes.