TRV on the return side.. don't know if they are bidirectional. Pic attached

[Samsg30]

Hi,

I have got 14 radiators in total and three of them have got TRVs installed on the return side.

2 of them are downstairs which are not heating up too much as compared to all other radiators.

I went through balancing myself (have to do it again little better this time).

Could anyone please tell me from the pictures if these TRVs bi-directional and if not, then what issues would I expect?

Pictures are of save TRV from top, front and back to show arrows and markings. I have put 'R' sign myself so I know which ones are on 'Return'

 

[Samsg30]

Also I noticed, LSV has got similar arrow... some pointing upward and some downward and all installed vertically. Now the issue is.. same LSV and TRV installed in 10 out of 14 radiators and they are in all possible combinations... e.g.

one radiator has got TRV and LSV arrow pointing downards
Other radiator got TRV arrow downward installed in flow and LSV arror upward installed in return
Another rad got TRV arror downards in flow and LSV arror downards in return etc

I can imagine single arrow means unidirectional as other searches on google suggest but I am struggling to understand any complications it would create to the system heating. I am trying to balance radiators as per suggesstions on google but no point if incorrect valves installtion are making them ineffective.
At the same time I do not want to take risk getting these valves interchanged / replaced if it doesn't matter as such having them in wrong place.. but they why bidirectionals are sold?

Sorry too many questions but I am baffled how someone can mess up that much.

 

[D_Hailsham]

Also I noticed, LSV has got similar arrow... some pointing upward and some downward and all installed vertically.

If you are talking about the large triangle on the side of the valve, I think they are just manufacturer's trademarks not arrows to show the direction of flow. As no arrows are visible, I would say they are single direction valves. They also look like commercial, not residential valves.

What is under the cap of the LS valve in the latest pic? Is it a pin which can be pressed down or something with flats which can be turned, eg with pliers?

 

[petit_pablo]

You tend to get noise on the trv as its shutting down if it's not bi-directional. Other than that it doesn't realy matter.

 

[petit_pablo]

They also look like commercial, not residential valves.

What is under the cap of the LS valve in the latest pic? Is it a pin which can be pressed down or something with flats which can be turned, eg with pliers?

They aren't commercial and your lack of plumbing experiance is shining through here.

 

[gasmanstu72]

turn off all radiators bar one, put your heating on and slowly turn down the TRV, if it starts vibrating and sounds like a machine gun it's on the wrong way.
but like Pablo says it'll still work.
bi-directional valves make for an easier install

 

[Samsg30]

Well, I live in an estate built by builder, so I am not surprised if they have used trade valves for all the houses here. It's valve to be set using L N key.

Though as others suggest, I'll try turning TRVs when heating is on to check any noise. If no noise, then I am relaxed and no need to swap/replace.

 

[ianmcd]

if your TRVs are on the wrong orientation they will only make a noise while trying to close, sometimes if you close them slowly you can feel a clunk, but not always, if you do find some that are the wrong way round its no big deal just swap them from vertical to Horizontal and then they will be on the right way, both threads are the same and is a very easy job to do

 

[Samsg30]

Good idea Ian. I have not seen horizontal TRVs anywhere but guess it won't look too odd if I have to do it on one or two rads.

Just to confirm my understanding, switching position of TRV means partial or full draining of system unless I close the cold water inlet feed to F&E tank and bung cold water outlet and expansion feed pipe?

 

[ianmcd]

Good idea Ian. I have not seen horizontal TRVs anywhere but guess it won't look too odd if I have to do it on one or two rads.

Just to confirm my understanding, switching position of TRV means partial or full draining of system unless I close the cold water inlet feed to F&E tank and bung cold water outlet and expansion feed pipe?

Yep just bung it and have a towel under when you are doing it it only takes about a min to change them round if it needs done , Horizontal fitting is very common

 

[D_Hailsham]

They aren't commercial.

Thanks for putting me right. It was the lack of chrome plating which confused me. I assume they are a well know manufacturer with a RWC logo on the sensor.

It's valve to be set using L N key.

I think you mean an "Allen" key.

Danfoss make that type of lockshield valve, so maybe they made the TRV.

 

[ianmcd]

the name on your TRV Reliance water controls are a well known company for making temperature mixing valves etc but I personally have never seen a TRV made by them but that doesnt mean they dont exist

 

[simond]

RWC are large Australian company who make a huge range of products.