Polyplumb under the floor when installing c/h

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When plumbers install central heating. Under floor in a customers home and use polyplumb. Do they tend to pressure test or Just fill the system. I know. It says to pressure test to 18bar in polyplumb instructions.
 
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When plumbers install central heating. Under floor in a customers home and use polyplumb. Do they tend to pressure test or Just fill the system. I know. It says to pressure test to 18bar in polyplumb instructions.
No , a plumber would not likely pressure test a domestic heating system to 18 bar .
Don't know what instructions you are referring to ,but you may have your wires crossed.
Edit. Just read the instructions for polyplumb ( don't use the stuff myself ,would use soldered copper) and it does actually state 18 bar .
 
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I always fill the system to 2.5 bar and leave it overnight. I just schedule the work during the install so the main pipework with any fittings is all in and can be pressurised and left till the morning. As long as it's still watertight in the morning then I can carry on.

I especially do that with an old open vented system that's being converted.
 
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and it does actually state 18 bar

If I was to install a pressurised system then I would test at a pressure equal to the incoming mains pressure to ensure that the pipework would be able to cope with faults that put mains pressure onto the pipe work. ( I do not 100% trust PRVs Regulator or Relief )
 
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The reason polypipe say 18 bar for polyplumb is that is an “O” ring first fitting, this means that when the pipe is inserted into the fitting it passes through the “O” ring first then the “grab ring” second.
If not fully inserted the “O” ring can hold the pipe when the pressure is increased even if the pipe has not passed through the grab ring, hence the 18 bar test. This could result in a full bore blow off.
Grab ring first fittings, like the new Hep2o and polymax only need 1.5 times the working pressure, if they are not pushed fully home they will leak but not blow off.
 
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The reason polypipe say 18 bar for polyplumb is that is an “O” ring first fitting, this means that when the pipe is inserted into the fitting it passes through the “O” ring first then the “grab ring” second.
If not fully inserted the “O” ring can hold the pipe when the pressure is increased even if the pipe has not passed through the grab ring, hence the 18 bar test. This could result in a full bore blow off.
Grab ring first fittings, like the new Hep2o and polymax only need 1.5 times the working pressure, if they are not pushed fully home they will leak but not blow off.
So as long as pushed all the way home things should be OK?
 
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So as long as pushed all the way home things should be OK?
Good practice is to mark the pipe with the socket depth so you know that the pipe is fully home then pull back on the pipe to ensure the teeth bite, in reality this doesn’t happen.
You can always double check by pushing on the pipe to see if there is any movement but if in full socket you should be fine.
 
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Always wondered if I really needed to pull on the pipe after inserting on push fits, guess that’s a good reason to continue to do so.
 
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