I'm in the process of connecting up a new sink with a monobloc tap. The
tap came supplied with flexible tails, one end being a 12mm connector
for the base of the taps. Fair enough so far.

The other end of the tail, however, has a connector with a captive nut
and rubber washer which looks *like* a 1/2 inch BSP as [1], though I've
no way of knowing for sure. I was expecting a 15mm compression fitting.

The end of my pipework currently has a service valve with a currently
empty compression fitting. If I remove the compression nut from the
service valve the captive nut on the tail is a perfect fit. Is this how
it's inteneded to work?

If I wanted to lengthen the tails could I use a coupler [2] and a pipe
1/2" hose [1]? In general, is a 1/2" BSP (or what I have) always
compatible with the thread on a 15mm compression joint.

Thanks for the help.


[1] 1/2" hose - http://www.screwfix.com/app/sfd/cat/pro.jsp?id=66800
[2] Coupler - http://www.screwfix.com/app/sfd/cat/pro.jsp?id=12561

On Fri, 21 Oct 2005 04:48:35 -0700, urchaidh wrote:

I'm in the process of connecting up a new sink with a monobloc tap. The
tap came supplied with flexible tails, one end being a 12mm connector
for the base of the taps. Fair enough so far.

The other end of the tail, however, has a connector with a captive nut
and rubber washer which looks *like* a 1/2 inch BSP as [1], though I've
no way of knowing for sure. I was expecting a 15mm compression fitting.

The end of my pipework currently has a service valve with a currently
empty compression fitting. If I remove the compression nut from the
service valve the captive nut on the tail is a perfect fit. Is this how
it's inteneded to work?

I believe so. The correct fitting is 1/2" MaleIron to 15mm compression so
the flat end of the MI seals against the rubber washer. Compression
couplers or service isolators with the back-nut and olive removed also
work but you may find the end has a bit of damage which stop the seal.



If I wanted to lengthen the tails could I use a coupler [2] and a pipe
1/2" hose [1]? In general, is a 1/2" BSP (or what I have) always
compatible with the thread on a 15mm compression joint.

Almost all compression fittings are to BS 864 or equiv and you'll find the
thread is 1/2 BSP.


--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at http://www.diyfaq.org.uk
Gas fitting FAQ http://www.makewrite.demon.co.uk/GasFitting.html
Sealed CH FAQ http://www.makewrite.demon.co.uk/SealedCH.html

Ed Sirett wrote:
I believe so. The correct fitting is 1/2" MaleIron to 15mm compression so
the flat end of the MI seals against the rubber washer. Compression
couplers or service isolators with the back-nut and olive removed also
work but you may find the end has a bit of damage which stop the seal.

Thanks, that makes sense - the correct solution would be to add a
section of copper pipe and one of these:

http://www.screwfix.com/app/sfd/cat/pro.jsp?id=18515


However, if the end of my service valves are free from dents, dings and
burrs such that I'd get a good seal the that should be OK.

Thanks.