Feed and Return pipes with no radiator

[voicey]

Any idea how to determine which pipes are feed/return when the radiator has been removed? I don't have it to put back on and need to figure out which side to put a TRV.

Cheers...

 

[onecog]

Just put a bi-directional TRV

 

[voicey]

Just put a bi-directional TRV

I have bought Danfoss TRV's which have a collar to change the direction of flow - am I going to do any damage if I run the TRV's the wrong way round for the first time the boiler is fired up?

Cheers...

 

[Jackrae]

So, am I correct in assuming you have a pressurised system in operation with two tails blanked off, or is it still a "dead" system with no pressure.

 

[Agile]

If you close all the rad valves, disconnect the one you are wanting to identify and then blow air ( or even water ) back to the boiler position where you disconnect one pipe and see where the air comes out.

But as TRVs now work in either direction it is not essential that they are connected on the flow.

Having said that I still think they work better from a water flow perspective when fitted on the flow.

But they also better monitor the air temperature when fitted on the cooler return!

Normally I fit them to the end of the rad which is easier to reach and/or at the cooler end of the rad from a room heat loss aspect.

Tony

 

[voicey]

We have a normal gravity fed CH system. I've had the living room replastered and took the rads off in there (and binned them). The valves are still in place and the system is still full of water (we're not running it as it's too warm).

I am going to drain down the system and replace all the downstairs rads and valves inc fitting TRVs. However, I neglected to check where the feed and return pipes were!

I will fit the TRVs as guided by Agile and switch the collar in the TRV if I get them wrong!

Thanks for the advice...

 

[Jackrae]

One simple test is to connect a length of tubing, say 10mm copper between the two valves, open one slightly and fully open the other. Turn on heating and feel which of the two feed pipes gets hot first. That is the flow line.

 

[Armo74]

Make sure you consult your boiler manufactures instructions as an automatic bypass valve may need to be installed if you fit TRV's to your rads.