Radiator TRVs

[Hardley]

Hi All,
A friend offered to move a radiator for me and add a small radiator, whilst I was on holiday.
When I returned I noticed that two of the radiators have the TRVs on one pipe, but the third rad has the TRV on the other pipe, friend says this will not matter, but I am concerned that third rad will not work.
What do you experts think.
Thanks
Hardley

 

[Rob]

I am concerned that third rad will not work.

Why not try it?

 

[raymondbowon]

It depends whether they are bi-directional or not. If they have two arrows going either way on the main chrome body of the valve you should be ok. If there is just one arrow then it wont work properly.

 

[spacethegas]

It depends whether they are bi-directional or not. If they have two arrows going either way on the main chrome body of the valve you should be ok. If there is just one arrow then it wont work properly.

that is not necessarily the case, it depends which way round the valve is fitted.
in any case the chances are that the valve is bidirectional (most are now) & it will be fine.
if the system develops juddering noises, vibration when c/h is on this may indicate a problem.

don't worry about it.

 

[Hardley]

Thanks for your replies, I did not want to try it out, as if it is wrong i've got to drain down again, to change TRV over to the other pipe.

TRV is fairly old and has two arrows on the body, both pointing upwards.

This radiator is the last one, in the room, assume water then goes back to the boiler for reheating.
Hardley

 

[spacethegas]

turn heating on.
hold pipes at either end to determine which gets hot first.
now you know which direction.
compare that to the arrows.