Adjusting TRV in one room changes the temperature in others

[MarkRo]

Hi,
If I turn the TRV down on the radiator in my bedroom it makes the radiators cold in my other two bedrooms. It doesn't seem to affect the ones downstairs. The radiators were installed by the previous owner and probably not done professionally. Any ideas on how to fix this would be gratefully received!

 

[ianmcd]

The upstairs has been installed as a one pipe through system by the sounds of it, if you want to use TRVs on them you will have to re-pipe the circuit

 

[MarkRo]

Thanks for your help

 

[Agile]

It may well be that there is some problem making the connections in the correct parallel way.

Either that or the DIYer before was incredibly stupid or possibly just mean and lazy!

Tony