stability of compression joint for exposed shower

[chellechelle]

Hi,
I have bought myself a shower fixing plate to attach my exposed thermostatic valve to. My concern is that the 90° connector supplied is a compression fitting onto the 15mm copper and not a solder. The connector is designed so that it can be screwed to the fixing plate thus won't suffer any movement.
How can I make the best compression joint ever, so I can sleep peacefully at night not worrying about a drip behind my tiles? Should I try to source a solder version of the connector?

Picture of my fixing plate attached as I'm not sure that I've used the best terminology.

Untitled

• chellechelle
• 31 Dec 2012
• 1

 

[denso13]

Compression will be fine, nice and tight but not too much. You could use these if you would prefer http://www.amazon.co.uk/SHOWER-MIXER-FIXING-CHROME-ROUND/dp/B009M4KOT2 which means you could use solder fittings in the wall.

 

[joe-90]

That round one is nice. I'll use that in future.

 

[chellechelle]

Thank you, I'll go for it and leave it exposed for a few days to check for leaks....it's that tight but not too tight that confuses me!

Happy 2013!

 

[joe-90]

If you twist it too tight it compresses the pipe like a waist - not good.

 

[chellechelle]

Nice analagy, makes sense. I've also read about ptfe tape around the olive, though I must admit I've always put it around the thread, no wonder I'm a bit concerned about dripping compression joints hopefully I'll get over it with my next joints!

Thanks all

 

[holty]

I've also read about ptfe tape around the olive, though I must admit I've always put it around the thread

2 problems, when people think ptfe should be round the thread. is that its not sealing anything. and eventually you can stress the nut, thats not designed for it. and can eventually crack causing a leak. i usually use a ptfe based paste on the olive like plumb blue. tape is ok. lsx possibly.

 

[Whitespirit66]

No PTFE required on the compression olive or thread. Smear of jointing compound like Boss White or similar. Maybe, as it's a critical hidden joint, I would consider Fernox LSX instead. Bit of extra insurance.

Compression joints should be hand tightened, then approx half turn with spanner. A LITTLE bit too tight won't cause a leak. Too loose will. After a while, you will get a feel for the correct tightening of compression fittings.

http://www.fernox.com/products/traditional+plumbing+products/jointing+compounds/ls-x

 

[neiltheplumber]

i would reccomend jet blue plus, suitable for potable water. Hand tight then half turn, then turn on water and check for leaks, if any turn another quater. Better not to overtighten straight away!

 

[chellechelle]

Just been trying out the fixing plate for fit. Because I have a fixed riser coming from the valve the distance between the valve and the finished tiled wall needs to be greater than that achieved with the elbow connector.

I'll look into the connectors from amazon which denzo mentions.

 

[keego]

i would reccomend jet blue plus, suitable for potable water. Hand tight then half turn, then turn on water and check for leaks, if any turn another quater. Better not to overtighten straight away!

+1 always use Jet Blue.