Speedfit fittings and copper pipe issue relating to verdigris

[smallsteve1]

Realise this is an odd question, but I was searching around on the Internet today and I came across a comment from a plumber discussing verdigris caused by the teeth on Speedfit fittings; they are there if you look very closely! He reckoned it wasn’t that uncommon and provided pictorial evidence, but I’ve never heard of it.
I’m doing a full bathroom refit at the moment and was planning on mixing copper and plastic where convenient, but i’m now starting to doubt whether it is a good idea and instead, thinking maybe I should be using compression joints instead!?
I did a little bit of checking and indeed it is not a good idea to mix stainless steel with copper. I even contacted John Guest and asked them about it but they were fairly dismissive.
Anybody got any experience of this one way or the other? I realise it is not uncommon to do this, but that self doesn’t necessarily mean it’s a good idea.

TIA

 

[Madrab]

Yup, you may get the slight galvanic corrosion from the copper to the S/S teeth in the grab ring of both JG and HEP and any other pushfit TBH as they all have them. More so in damp conditions that then acts as a electrolyte. The contact points are minimal though, so the corrosion also tends to be minimal.

See a little greening sometime in fittings where condensation is common, nothing new there but never seen it to the degree where I was overly concerned

 

[smallsteve1]

Yup, you may get the slight galvanic corrosion from the copper to the S/S teeth in the grab ring of both JG and HEP and any other pushfit TBH as they all have them. More so in damp conditions that then acts as a electrolyte. The contact points are minimal though, so the corrosion also tends to be minimal.

See a little greening sometime in fittings where condensation is common, nothing new there but never seen it to the degree where I was overly concerned

Thanks for that.

Some of the joints I need to make will be under the shower tray and extremely difficult to get to once installed. This is why I thought it a good idea to use speedfit as opposed to compression joints, to avoid issues of backing off which you can get with compressions. am I making the right choice?

 

[Madrab]

The golden rule is not to bury compression fittings where they can't be got at. That being said I've yet to come across any compression fitting that has come apart under a floor or in a wall. I think it comes more from the fact that if the pipe that it's connected to it is pushed/pulled or under stress then the hidden compression fitting can be the weak point and can loosen and leak

If you are at all worried then the only other option would be to use barrier pipe and not use copper. Or if using copper is a must then start practicing soldering

 

[oldbutnotdead]

For anything which is going to be inaccessible once you've tiled, fitted bath etc. then solder and copper OR continuous placcie runs with no couplings will be your best bet.
If your experience level is low then pushfit are easier to get right.
You must use the correct inserts for the pipe you are using (no-name couplers with Speedfit pipe is fine as long as you use Speedfit inserts. No-name pipe with Speedfit couplers again is fine as long as you use no-name inserts in the pipe)
Any copper- must be clean, deburred, round, no dents.
Placcie- if you have to cut it use a proper cutter (not a hacksaw), make sure there are no scuffs or nicks in the surface where it is going into the coupler.
At couplers, make sure there are no significant forces acting on the joints (so pipes into an elbow are actually meeting at 90 degrees, not 80, not 100, pipe lengths are correct so if anything the pipes are being pushed into the coupler rather than being pulled out of it)
MAKE SURE YOU PUSH THE PIPE ALL THE WAY IN.

 

[drives]

I was in the same position with a bathroom refit and limited plumbing experience. I would advise buying a soldering torch and yorkshire fittings- ideal for the novice.

 

[smallsteve1]

I was in the same position with a bathroom refit and limited plumbing experience. I would advise buying a soldering torch and yorkshire fittings- ideal for the novice.

I’ve got a fair bit of plumbing experience along with the tools and know-how, but there is reason why I haven’t gone full copper.

The question was really about whether Speedfit or compression joints are better in difficult to reach areas. The prime consideration being around compression joints that can ultimately back off i.e. the nut eventually loosens to the point where the joints start to weep. I guess Speedfit has less of an issue on this front, but not 100% sure.