Mon, 25 May 2026 22:12:08 +0100 https://www.greenbuildingforum.co.uk/newforum/ Lussumo Vanilla 1.0.3 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=206970#Comment_206970 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=206970#Comment_206970 Tue, 12 Aug 2014 11:27:28 +0100 Shevek
Am I right in saying that 1/2" and 3/4" brass fittings will fit these respectively?

And what does the R, G and B stand for? And what does the 1 in G1B stand for?]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=206973#Comment_206973 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=206973#Comment_206973 Tue, 12 Aug 2014 11:57:50 +0100 Triassic
whose diameter increases or decreases along the length of the thread; denoted by the letter R.

Taken from http://en.wikipedia.org/wiki/British_Standard_Pipe

Note sure about B?]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=206984#Comment_206984 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=206984#Comment_206984 Tue, 12 Aug 2014 14:31:17 +0100 dimengineer R = Tapered thread.

G normally needs a washer or something to seal properly.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=206987#Comment_206987 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=206987#Comment_206987 Tue, 12 Aug 2014 15:05:04 +0100 Triassic http://www.ring-plug-thread-gages.com/PDChart/G-series-Fine-thread-data.html]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=206995#Comment_206995 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=206995#Comment_206995 Tue, 12 Aug 2014 16:27:03 +0100 Shevek
Edit: this data sheet also it refers to it as "G1B (R3⁄4)" http://kamstrup.com/media/16684/file.pdf

Edit 2: and there's also "G3/4B" thread designations on page 16 of this document: http://kamstrup.com/media/16718/file.pdf]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=238567#Comment_238567 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=238567#Comment_238567 Tue, 05 Apr 2016 22:20:37 +0100 Shevek
I don't know quite where to measure but basically inside of thread is about 30 mm and outside of thread is about 33 mm.

I need to go from this to a 22 mm copper pipe (or send it back to supplier). Any thoughts? I'm hoping it's simply a 1" thread, so I can use a 22 mm x 1" compression female iron.

Edit: added a screenshot of the size chart. I'm 4th one down.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=238568#Comment_238568 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=238568#Comment_238568 Tue, 05 Apr 2016 22:52:41 +0100 Ed Davies
That matches within reasonable measuring tolerance with the page Triassic references above:

http://en.wikipedia.org/wiki/British_Standard_Pipe

Nominal size: 1"
Minor diameter: 30.292 mm
Major diameter: 33.249 mm

PS, pick up a £8 set of digital calipers from Lidl next time they have them. Only used mine half a dozen times but they've been very handy when I have.

http://www.hotukdeals.com/deals/digital-vernier-calipers-7-99-lidl-473355

PPS, cross-posted with Shevek's edit.

PPPS, what's the plumbing fitting? A flow meter?]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=238572#Comment_238572 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=238572#Comment_238572 Tue, 05 Apr 2016 23:18:11 +0100 Shevek https://www.kamstrup.com/en-en/products-solutions/water-meters/residential-water-meter

Edit: duh, and of course I already have a set of callipers! Clearly I still haven't got used to the idea of going to grab them instead of a ruler, lol]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=238614#Comment_238614 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=238614#Comment_238614 Wed, 06 Apr 2016 20:41:34 +0100 Shevek
The thread on compression fittings are generally 20 mm deep, whereas the thread on the meter fitting is only 13 mm. So I can't screw it on far enough to make contact with the EPDM washer.

Are there fittings out there with a shorter thread? I can't find any. Will an end feed female iron be any shorter? ]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=238624#Comment_238624 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=238624#Comment_238624 Wed, 06 Apr 2016 22:36:15 +0100 Ed Davies
https://www.stilldragon.eu/en/adapters/194-1-inch-bsp-half-coupling.html

Contrast with their full coupling:

https://www.stilldragon.eu/en/16-adapters

Not quite what you want but could either be a clue to more-useful searches or you could use as shown with a short bit of pipe with longer 1" thread on each end.

I wonder if the half length is what the “B” in “G1B” means. Google doesn't seem to know.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=238625#Comment_238625 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=238625#Comment_238625 Wed, 06 Apr 2016 23:00:16 +0100 Shevek https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=238627#Comment_238627 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=238627#Comment_238627 Wed, 06 Apr 2016 23:19:55 +0100 Shevek http://www.jtmplumbing.co.uk/pipe-fittings-c433/endfeed-fittings-8mm-28mm-c117/jtm-endfeed-straight-cylinder-connector-pp426]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=238628#Comment_238628 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=238628#Comment_238628 Thu, 07 Apr 2016 00:15:46 +0100 Gotanewlife https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=238634#Comment_238634 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=238634#Comment_238634 Thu, 07 Apr 2016 09:43:31 +0100 Ed Davies https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=238653#Comment_238653 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=238653#Comment_238653 Thu, 07 Apr 2016 14:42:37 +0100 ringi https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=238655#Comment_238655 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=238655#Comment_238655 Thu, 07 Apr 2016 15:13:18 +0100 Gotanewlife Posted By: Ed Daviesbut wasn't sure how well it would work with plastic to metal.I have done it loads of times and my house/garden is littered with such joints.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=238661#Comment_238661 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=238661#Comment_238661 Thu, 07 Apr 2016 17:50:53 +0100 Ed Davies https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=238711#Comment_238711 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=238711#Comment_238711 Sat, 09 Apr 2016 15:42:01 +0100 Shevek
Cylinder connectors don't work because they have a different thread. (shame they would have looked the tidiest)

But I got these DN20 unions off the company that sold me the meter. They have a female BSP thread length of around 14-15mm. And I'll fit a compression or end feed coupling to these.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=238718#Comment_238718 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=238718#Comment_238718 Sat, 09 Apr 2016 17:19:15 +0100 Ed Davies
I believe you can use Yak hair to seal the threads:

http://sethgodin.typepad.com/seths_blog/2005/03/dont_shave_that.html ]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=238720#Comment_238720 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=238720#Comment_238720 Sat, 09 Apr 2016 17:55:28 +0100 Shevek
Either way won't need the string, although I would like to be able to say there's Yak hair in my plumbing.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=238737#Comment_238737 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=238737#Comment_238737 Sun, 10 Apr 2016 00:13:14 +0100 Gotanewlife Posted By: ShevekIs this what you mean by pipe string? http://www.plumbcenter.co.uk/product/jet-hemp-dispenser-80g/
No def not!!! Look here:
http://www.loctite.co.uk/pipe-sealing-9886.htm
The small space left might disturb the water slightly but it will be inconsequential.
Paranoia is creeping in here: Keep it Simple!!!]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=238913#Comment_238913 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=238913#Comment_238913 Sun, 17 Apr 2016 02:56:26 +0100 Shevek
I used PTFE + pipe thread compound on these joints so why are they leaking?]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=238920#Comment_238920 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=238920#Comment_238920 Sun, 17 Apr 2016 10:57:53 +0100 Gotanewlife
Too late now but there is no such thing as too many gate valves. Sadly I notice there is no valve on the furthest right CW pipe. So that's a lot of draining before you can get to the thing. So don't be cheap and quick about this: cut that lowest copper pipe where it runs horizontally towards the right wall and fit a valve while you are at it - remember this is a cheap chinese meter....

Win some lose some - but learn every day....nice tidy work btw!]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=238921#Comment_238921 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=238921#Comment_238921 Sun, 17 Apr 2016 11:49:57 +0100 Shevek
The problem isn't the joint to the meter (I went with rubber washers for there), it's the joint between the unions and the female compression couplings. I didn't use a washer at all on that joint, I thought you simply use compound and PTFE. In fact I've opened that joint up and I don't see how a washer would even work as there's no real face to seal against.

It's my first shot at copper plumbing so I was expecting something like this, just preferably not at 3 in the morning, lol.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=238923#Comment_238923 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=238923#Comment_238923 Sun, 17 Apr 2016 12:50:05 +0100 Gotanewlife
I guess you just messed up with your PTFE tape. Done right the thread lock isn't needed.

My first plumbing job was installing a 40kW wood burner, 2500ltr TS and all the associated gubbins; never had a problem at 3am mind but I didn't install enough gate valves or 3-part fittings so 1/sometimes getting stuff apart is a nightmare and 2/one day I might have to drain down a couple of thousand litres of water with several hundred pounds worth of anti-rust in it - scary, very scary.

You are going to make a significant effort with the pipe insulation etc I assume - I realise it is inside the envelope but still loads of benefits to putting some effort in.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=238924#Comment_238924 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=238924#Comment_238924 Sun, 17 Apr 2016 13:00:39 +0100 Peter_in_Hungary
I think I would have used soldered fittings instead of the DN20 unions from the company and saved the trouble / expense of the compression fittings plus the DN20 fittings.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=238925#Comment_238925 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=238925#Comment_238925 Sun, 17 Apr 2016 13:15:51 +0100 Shevek
I'm using two types of compound: jointing compound, which I've been using on the end of the pipe with compression fittings. And pipe thread compound, which I've been using in conjunction with PTFE tape for threaded connections (including the aforementioned failed joint). I'll get some Loctite 55 and hopefully that'll do the job (shame it's a bit hard to get hold of).

Wasn't planning on insulating those pipes. I'll see how it goes with condensation on the cold ones and maybe change my mind.

Thanks for your help guys.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=238927#Comment_238927 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12437&Focus=238927#Comment_238927 Sun, 17 Apr 2016 13:45:07 +0100 Gotanewlife Posted By: ShevekI'll see how it goes with condensation on the cold onesShouldn't need it in there - I was thinking of the hot ones.]]>