Do I have a one-pipe or two-pipe central heating system?

[dominoman]

All the pipes are under the floor.

Is there any easy way to know whether I have a single pipe or dual pipe central heating system?

I'm hoping I have 2-pipe, as from reading here it seems they work better, but I don't know!

Thanks,
Mike

 

[Agile]

You should assume its a two pipe as one pipes are rare.

If you can measure exactly the flow and return temps on each rad that would confirm.

But a contact thermometer is needed.

Tony

 

[durhamplumber]

One pipe systems only have one valve on radiators.two pipe systems have a valve both ends

 

[stardanny]

One pipe systems only have one valve on radiators.two pipe systems have a valve both ends

Not true, radiator always has both valve fitted. Radiator valve is tee off flow pipe and the other valve on same radiator tee back onto same flow pipe, this is the one pipe system.

Op, one pipe system is a bit rare, how old is your system?

Daniel.

 

[holty]

[/quote]
One pipe systems only have one valve on radiators.two pipe systems have a valve both ends

Not really. Youll, more than likely see one pipe enter the top of the rad(flow) and exit the bottom with swept tees . But seen one pipes with both bottom entry's. Seen 2 pipes with flow at top as well. Some might say they shouldn't have trvs. Yet there are trvs available that are suitable, At cost. So basically without exposing the circuit pipework its a guess, maybe a thermal camera might be an answer.

 

[dominoman]

Op, one pipe system is a bit rare, how old is your system?

Daniel.

It's pretty ancient looking but hard to tell. Radiators are mainly cast iron, with a few rolled steel 70s replacements. The boiler is a Potterton Suprima, maybe 10-15 years old. And the cylinder looks like it was built in victorian times. All the pipework has been hacked and patched so many times - mostly either by a DIYer or a shoddy plumber as it runs at odd twists and angles and isn't properly fixed to the walls.