TRV's. Can they go on either flow or return side of the rad?

[wild nomad]

Hi there,

Well, just as the title says. I have to re-hang some rads that have been taken off the wall by someone else. That person did not mark which pipes were flow or return and its impossible to trace because the pipes (Plastic, 10mm micro) disappear into the ceiling, I presume to some form of manifold. The room is under construction so the pipes are just hanging from the ceiling free. In a word it's a bit of a mess.

It's not really a problem so long as the TRV's that are on the rads will still work on the return side of the rad as well as they do on the flow side. So that's my question in a nut shell. Do TRV's work on both sides of a radiator?

Thanks in advance
Mike

 

[Simon F]

yes and no.
have a look at the trv, should have arrow/arrows showing flow direction.
newer valves tend to be bi direction but not so if they are older!

 

[wild nomad]

yes and no.
have a look at the trv, should have arrow/arrows showing flow direction.
newer valves tend to be bi direction but not so if they are older!

Hi Simon,

Thanks for the rapid response.

Yes, the valve has arrows. one points to the rad input, the other to the pipe input. Does this mean I can put it on the return side of the rad or just that I can move the orientation of the valve to be both vertical and horizontal?

 

[Millsy 82]

Yep it will go on flow or return

 

[wild nomad]

Cheers Simon, good news!

Thanks

 

[kris]

Only if they are bi directional and some require a tiny adjustment. Ie the danfoss ones have a direction arrow on them which can be turned depending on direction of flow. If they arent bi directional then you mustnt mix up .

 

[happyflyer]

Oh what was life like before the TRV, it was good, but energy was cheap, TRV is a cheap old way of getting some small form of control, not very accurate.

 

[WHPES]

I have found that if you put some supposed "bi directional" valves on the return, they make the most awful rattling noise. You are always best to have the water going into the bottom of the valve and out of the angle regardless of what type it is. If space prevents this you can put them on the return side with the thermostat sticking out horizontally.

 

[wild nomad]

Well, the whole problem is that I'm confronted with a bunch of pipes hanging down from the ceiling and no way of knowing which pipe is flow or return. Just wanted to see if TRV's go on both sides of the rad. Results seem inconclusive....

 

[Scott_D]

Use matching trvs and lockshields.
If there is an issue you can swap them round

 

[wild nomad]

Ok thanks everyone! Good advice as always. Rock stars!

 

[happyflyer]

Rocks Stars??? Like Elvis, Nay, bad comparison there wild :hand: we are mainly plumbers on here, bottom feeders, I heard they are making plumbing a trade next year.:thinking:

 

[happyflyer]

Not much going on on UKPF and the footballs over, mind you most people got the heating turned off, wait until October, wall to wall " I am new on here, so be gentle with me "

 

[so-solar]

Danfoss are the only true bi directional trv on the current market, all other valves are pre tensioned to slow the valve shutting down! In time you will incur problems

 

[Alex Knight]

Why not just link the pipes together flick the heating on and see which one gets hot first?