Radiator valves on single pipe system

Arnela

Morning guys,

So im looking to have the last to old radiators replaced upstairs in the bedrooms. Our heating system is a single pipe system. I was looking at getting trvs installed but I have read that they need to be specially for single pipe systems and im struggling to find any that don't cost stupid money. Im now thinking that I will just replace the manual valves. Do the manual valves need to be anything special or are they standard?

dnpark38

Looks like mine and I've got normal TVR s on.
I understand one radiator hasn't to have them so bathroom doesn't in my case.

tacpot12

Call Pegler Technical support to check if these will be suitable: https://www.ebay.co.uk/itm/306638731439

The Belmont range is a commercial range with higher flow rates and some valves in the range are suiable for single pipe systems. 

Rodders53

Why change the valve(s)? Looks to be nowt wrong with that particular valve that a little clean and polish won't fix.

Single pipe TRVs may be expensive / more difficult to source but should help with comfort and control.  The alternative costs of re-plumbing to a two pipe system is far greater.  Allegedly standard TRVs can work in some single pipe cases; so it's a matter of how lucky you feel if DIY...

Albermarle

dnpark38 said:

Looks like mine and I've got normal TVR s on.
I understand one radiator hasn't to have them so bathroom doesn't in my case.

But is yours a single pipe system? Most are not and you can not tell just by looking at a radiator.

dnpark38

A 15mm pipe runs to each radiator in turn and from last radiator returns to boiler, each radiator has a bypass.
Piping is many years old as was the way older systems were done prior to the use of small bore pipes and plastic.

Albermarle

dnpark38 said:

A 15mm pipe runs to each radiator in turn and from last radiator returns to boiler, each radiator has a bypass.
Piping is many years old as was the way older systems were done prior to the use of small bore pipes and plastic.

Yes one pipe systems are usually in older properties where the system has not been upgraded. However both one pipe and two pipe systems typically use 15 mm pipe to the radiators.
Microbore and plastic are less common generally AFAIK.

plumb1_2

As an apprentice used to fit one pipe systems and only with one valve, the other side with a bent male iron. No balancing involved.

Op check which pipe getting hot first, that’ll give you the direction of the flow. Buy danfoss RAS-c2 valve sets , they have the ability to swoop the direction of the flow by just turning a small directional indicator wheel. So if you get it wrong you can swop it in 2 seconds 
Dont buy cheap valves £7 etc buy £15 to £20