In article , Cicero
writes

I've just checked the two types from Wickes and allowing for some
variation in numbers my checks confirm that there are two different
sizes for different fittings thus:

Push-fit - 41mm - BS EN1451 B

Solvent weld - 43mm - BS EN1566 B - Mupvc

The difference in numbers suggests that there are different types of
solvent-weld pipe and probably different types of solvent which need to be
matched to their particular type.

Both ABS and MuPVC use the same solvent system.

ABS waste is thin walled, scratches easily and is the cheaper, low grade
product but it is adequate for domestic use.

MuPVC waste is thicker walled, less easy to scratch and can sustain
higher temperatures in use. It is specifically required for prolonged
discharge of hot water where ABS would soften and start to flop about
but is not generally required for a domestic situation. Its higher
temperature resistance makes it suitable for use as a flue for
compatible boilers such as the Keston range.

Both ABS and MuPVC wastes were specified under BS 5255 but have now been
given different EN spec numbers which is sensible considering their
different properties.

The sheds used to stock MuPVC exclusively so all my stuff is done in
that but on returning to buy some additional supplies at the B&Q I have
noticed that the stock seems to have switched the lower cost ABS with a
few odd fittings of MuPVC being sold from ABS part bins. If I want MuPVC
now it will be easier to go to a specialist drainage merchant where I
know I will get the right stuff.
--
fred
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