House manily pipes in copper with a tiny bit of plastic

[dilalio]

So I shouldn't be too concerned at not testing these few fittings at 18bar?

No. I wouldn't lose sleep over it!

 

[SandyLyon]

The difference in test pressures is correct.

Polyplumb is an "O" ring first fitting, as was the very first Hep2o fittings and the Hep2o "Slimline" fitting.

The last 3 versions of Hep2o have all been "Grab" first, what this means is that in the Polyplumb fitting the pipe passes through the "O" ring first and then through the "grab" ring, so if the pipe isn't inserted fully the "grab" may not be fully engaged and the possibility of a "full bore blow off" hence the higher test pressure of 18 bar.

With the "grab" first fitting, if not fully inserted you will not get a "full bore blow off" but a leak, with this type of fitting the recommendation is 1.5 times the maximum working pressure.

It is generally accepted that the "O" ring first type of fitting is more prone to "installer error"

 

[tomsim]

Thanks but in the case of just a few fittings on a copper system if you do make sure you fully insert etc. You should be ok without the 18bar test pressure?

 

[tomsim]

Would other people not worry about the absence of an 18bar pressure test on these few polyplumb fittings?

 

[SandyLyon]

The 18 bar test can only be done safely at first fix stage or when any other equipment is isolated (shower valves, taps, washing machine etc) so not to damage them.
As long as the pipes and fittings were clean and not damaged, copper pipe cut using a pipeslice, plastic pipe with a plastic pipe cutter and insert fitted, insertion depth marked on pipe and pushed fully home, a good pull back to check its holding and you should be ok.

 

[tomsim]

The difference in test pressures is correct.

Polyplumb is an "O" ring first fitting, as was the very first Hep2o fittings and the Hep2o "Slimline" fitting.

The last 3 versions of Hep2o have all been "Grab" first, what this means is that in the Polyplumb fitting the pipe passes through the "O" ring first and then through the "grab" ring, so if the pipe isn't inserted fully the "grab" may not be fully engaged and the possibility of a "full bore blow off" hence the higher test pressure of 18 bar.

With the "grab" first fitting, if not fully inserted you will not get a "full bore blow off" but a leak, with this type of fitting the recommendation is 1.5 times the maximum working pressure.

It is generally accepted that the "O" ring first type of fitting is more prone to "installer error"

So in my situation a may be better with hep2o. I ve use polyplumb and never had a problem before though. Are polyplumb saying 18 bar is.needed.for.the grab ring to fully bite? Or to make sure.the fitting is all the way in? I always witness mark the pipe.so know.its.fully in the.fitting

 

[SandyLyon]

The difference in test pressures is correct.

Polyplumb is an "O" ring first fitting, as was the very first Hep2o fittings and the Hep2o "Slimline" fitting.

The last 3 versions of Hep2o have all been "Grab" first, what this means is that in the Polyplumb fitting the pipe passes through the "O" ring first and then through the "grab" ring, so if the pipe isn't inserted fully the "grab" may not be fully engaged and the possibility of a "full bore blow off" hence the higher test pressure of 18 bar.

With the "grab" first fitting, if not fully inserted you will not get a "full bore blow off" but a leak, with this type of fitting the recommendation is 1.5 times the maximum working pressure.

It is generally accepted that the "O" ring first type of fitting is more prone to "installer error"

So in my situation a may be better with hep2o. I ve use polyplumb and never had a problem before though. Are polyplumb saying 18 bar is.needed.for.the grab ring to fully bite? Or to make sure.the fitting is all the way in? I always witness mark the pipe.so know.its.fully in the.fitting

The 18 bar test was devised to ensure that the pipe was fully inserted into the fittings, they found that in some installations joints could hold under friction from the "O" ring at fairly high pressures

Also I have seen instances were the fitting has been taken apart and reassembled with the grab ring either the wrong way round or left out altogether. Hence me saying to "tug back" on the pipe when you have made the joint.

As said above, "O" ring first fittings tend to create "Full Bore" leaks when a joint is incorrectly made, there is nothing wrong with this type of fitting as long as they are installed correctly

As long as you have followed the instructions you should be fine.

Keep fittings clean / free from dust / grit etc
Use correct cutters
Use correct insert in plastic pipe
Mark the pipe
Insert pipe fully to the mark
Tug back

 

[dilalio]

These are our fittings of choice, having tried and tested them all. Just be aware, you'll need the tool for deconstructing them and if too close to another fitting, you'll never get them off, but they give you real confidence!

http://www.wavin.co.uk/web/solutions/potable-water/plumbing-systems/pushfit.htm

 

[SandyLyon]

These are our fittings of choice, having tried and tested them all. Just be aware, you'll need the tool for deconstructing them and if too close to another fitting, you'll never get them off, but they give you real confidence!

http://www.wavin.co.uk/web/solutions/potable-water/plumbing-systems/pushfit.htm

We only use Hep2o, the new version can't be tampered with, it's slim compared with the other pushfit fittings, it's joint recognition system is useful as a "double check" that everything's ok.

The Demounting tools are pretty cheap (we have 100's and never paid for one) Wavin do a metal Demounting tool for when 2 fittings are close together (spigot reducer into a socket) that are a handy addition to your toolbox.