3/4 inch - 22mm

[Trevor]

Hi

My house was built in 1959 so all my plumbing is imperial

I am in the process of changing the bathroom and have discovered

1/2" to 15mm converters.

I can not find anything for 3/4" - 22mm from what I can see both sizes look the same.

am I correct in my thinking?

Please don't shout at me I am asking as I do not know the answer.

Trevor

[tony sayer]

In article , Trevor scribeth thus

They do exist as I've used them!.

No good plumbers merchants around your way then?..

[Rod]

I never discovered 1/2" to 15mm converters. Most 1/2" pipe/fittings work acceptably with 15mm pipe/fittings.

3/4" to 22mm requires some converter mechanism - sometimes a special fitting, sometimes a special olive. (I once bought special olives from Focus. Had to take them back as they were entirely not special - just ordinary olives - and they did not work.) If you get real converter olives, they are just a touch smaller on the inside diameter.

If you try to use 22mm fittings on 3/4" pipe, expect a lot of leaks. :-)

Question for you. Why do you think we will shout at you?

[A.Lee]

Strangely, I cannot recall seeing any of those. It is not normally necessary to have convertors on 15mm to 1/2" pipe, as the outside diameters are so close, that most 15mm fittings work.

No. There is a large (in sealing terms) size difference between the 2. You can either get a larger olive for use with 3/4" pipe and 22mm compression fittings, or there are compression and solder fittings to convert the 3/4 to 22mm

22mm std fittings cannot be used successfully on 3/4" pipe. Alan.

[The Medway Handyman]

I PROMISE NOT TO SHOUT AT YOU!

[YAPH]

I've seen them in the catalogues but never bought any and I doubt I'd be able to tell which end is the 1/2" and which the 15mm, they're so close in size in practice!

No, they're quite different and you do need converters. You can get solder couplers, and 3/4" olives to use in 22mm compression fittings. I think there are also 3/4" push-fit fittings about.

Try A Real Plumbers' Merchant (tm) or BES (who are ARPM-by-post). Toolstation also do 22mm x 3/4" solder-ring couplers in packs of 25, which is too many for my needs.

[Trevor]

Thanks to all for the replies, I now know to find a good plumbers shop.

I thought my question was so obvious that everyone in the world knew the answer apart from me, hence I thought I would be SHOUTED at

Thanks again

Trevor

[YAPH]

About the only SHOUTING here is done by newbies coming in from brainless-dweeb forums where use of the Caps Lock key is even less advanced than basic spelling, grammar and punctuation. Er, LOL.

Gratuitous asking of frequently asked questions is likely to draw responses suggesting more or less curtly that answers might be obtained by "STFW", a quick look back over recent posts, or at the FAQ or wiki (see

instead of bothering us /real/ DIYers with the more pressing questions of where to file our files ;-)

[John Rumm]

While that is the theory, I have made a successful compression joint on

3/4" before using ordinary 22mm fittings. You do need to tighten it a good turn or so more to compress the olive down to size.

If completely stuck, you can also do it with an end feed capillary fitting and a pipe cutter. Run the pipe cutter round one end of the fitting just once but with the cutter done up fairly tight. We are not trying to chop the end off the fitting here, just reduce its diameter. This will dent the fitting around its circumference. Move the pipe cutter a few mm along and repeat. You should now have a fitting with one end a little bit smaller which can be soldered successfully onto a 3/4" pipe.

[mark]

Has nobody heard of a "green olive"?