20mm tee pipe fitting stuck when screwing on

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boland

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#302494 27-Nov-2022 16:18

Ordered a bidet online, but having trouble installing it. It comes with a tee pipe which goes onto the water supply, all good.

However, I can't get the connector of the pipe going to the toilet to tighten. It seems to be the right diameter as I can screw it on, but it's stuck after about 1 turn. Could the thread be different? Obviously it's leaking when I turn the tap back on. And, I don't want to use force to tighten either.

Any ideas?

tweake

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#3002206 27-Nov-2022 16:26

most pipe fittings here are BSP. you might have the american version which is NPT. they are the same size but different thread pitch.

Bung

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#3002211 27-Nov-2022 17:10

The 2 most common sizes, 1/2" (15mm) & 3/4"(20mm) have the same pitch but different thread forms. Is the fitting really 20mm? That seems large for a typical toilet cistern supply. More like a bath tap feed. https://sunshoweronline.com.au/help-centre/how-to-measure-bsp-threads-and-pvc-pipe/

boland

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#3002460 28-Nov-2022 09:54

Bung: The 2 most common sizes, 1/2" (15mm) & 3/4"(20mm) have the same pitch but different thread forms. Is the fitting really 20mm? That seems large for a typical toilet cistern supply. More like a bath tap feed. https://sunshoweronline.com.au/help-centre/how-to-measure-bsp-threads-and-pvc-pipe/

You're right, it's 15mm (1/2"), sorry.

So, I guess I'll need an adapter (bsp male to npt female), right? I found some options online, not a lot though.

Bung

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#3002524 28-Nov-2022 10:46

If you have a bsp male and an ntp female your adapter would be bsp female to ntp male as it sits in the middle.

boland

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#3002526 28-Nov-2022 10:49

Bung: If you have a bsp male and an ntp female your adapter would be bsp female to ntp male as it sits in the middle.

Thanks, but it's the other way around. I've got an NPT male (the T piece I bought online) and a BSP female (the connector on the existing hose).

wally22

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#3002565 28-Nov-2022 11:58

I would make sure that you eliminate all possible non (NZ) standard connections for ease of future maintenance. You have supplied no pictures so this advice is generic. i.e. a supplied T fitting not working may be problematic on all 3 connections.