Hi
Promised to go over and fit service valves to f-i-law's bathroom taps but don't know whether to expect metric or imperial pipework - he's not sure. So a few questions for those who know about these things :-
Many thanks Des
15mm = 1/2" ditto 1/2" = 15mm, yes they do fit. However 22mm does not = 3/4"
Peter
In message , Des writes
Compression works OK, it's a bit loose going one way and rather tight going the other, can't remember which way round though. Solder joints can be made to work but I find it easier to just use adapter fittings.
Not unless you have an accurate mircrometer, or cut the pipe (imperial pipe has a greater wall thickness, and smaller ID).
Yes. The OD is so similar that both compression and solder fittings are interchangeable.
[As someone else has said, this is *not* true for 22mm vs 3/4". You can use a 22mm compression fitting on 3/4" pipe with special olives - but not vice versa. If using solder fittings to join 3/4" to 22mm, you need special fittings which are 22mm one end 3/4" the other end] [For the pedantic, the 1/2" or 3/4" dimension of imperial pipe refers to the nominal ID - so the OD is somewhat larger.]Thanks for the replies - seems pretty conclusive.
Mind you, I'll still be feeling a little nervous when I make that first incision ;-)
Des
Don't worry - but you'll need to get all the paint off the ends of the old pipe before using any fittings on it. Go prepared with PollyStrippa, wire wool, etc.
You can get a 22mm to 3/4" olive for a few pence from plumbers merchant to put in the 22mm compression fittings.
LS
Here in Ireland, we still use imperial sizes, 1/2", 3/4", 1" etc. The sizes refer to outside diameter. Newer brass fittings are now marked 14.7 mm, 21 mm, 27.4 mm!!!
So we have sort of gone metric!!!
If using UK metric fittings I just replace the olives with Irish sizes.
FrancisJK
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