I am installing a gas hob and need to make a connection to an existing
gas copper gas pipe. Can I use a compression fitting to extend the
pipe to the hob, I was also going to puy a gas shut off tap in line as
well.The pipe pipe will be hidden behind a cooker, Can I use
compression fittings behind an appliance where access would not
normally be made or do I need to make a soldered connection first and
extend the pipe to the hob. I will of course use gas jointing
compound, what do you think about using gas PTFE tape on the thread as
well?

Thanks

"lawrie1" wrote in message
oups.com...
I am installing a gas hob and need to make a connection to an existing
gas copper gas pipe. Can I use a compression fitting to extend the
pipe to the hob, I was also going to puy a gas shut off tap in line as
well.The pipe pipe will be hidden behind a cooker, Can I use
compression fittings behind an appliance where access would not
normally be made or do I need to make a soldered connection first and
extend the pipe to the hob. I will of course use gas jointing
compound, what do you think about using gas PTFE tape on the thread as
well?

Gas cock is compression
but you really should be getting CORGI to check it and commission
the hob.
--
Vass

On 19 Mar 2007 01:01:12 -0700 someone who may be "lawrie1"
wrote this:-

I am installing a gas hob and need to make a connection to an existing
gas copper gas pipe. Can I use a compression fitting to extend the
pipe to the hob, I was also going to puy a gas shut off tap in line as
well.

Could you not use the gas cock to extend the pipe? Obviously this
depends on the location of everything.

The pipe pipe will be hidden behind a cooker, Can I use
compression fittings behind an appliance where access would not
normally be made

Behind a cooker is no different to the screwed joint that is used to
connect the pipe to the back of a cooker.

or do I need to make a soldered connection first and
extend the pipe to the hob. I will of course use gas jointing
compound,

Hopefully not on a soldered joint:-)

what do you think about using gas PTFE tape on the thread as
well?

On the thread of a compression fitting? They do not seal on the
threads. On a threaded fitting? This or another means of making the
joint gas tight is essential.

If you do decide to do the work yourself remember to check the
joints the proper way with leak detection fluid and pressure
testing.

People are only allowed to do gas work for themselves if they are
competent. While this is a way of avoiding the CORGI con it is not
advisable to work on gas unless one is competent.




--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54

"David Hansen" wrote in message
...

If you do decide to do the work yourself remember to check the
joints the proper way with leak detection fluid and pressure
testing.

Hardly pressure testing. I assume you mean soundness or hold-up check.

People are only allowed to do gas work for themselves if they are
competent. While this is a way of avoiding the CORGI con it is not
advisable to work on gas unless one is competent.

Agreed, which was why I didn't post.

Jim A

On Mon, 19 Mar 2007 11:10:51 GMT someone who may be "Jim Alexander"
wrote this:-

If you do decide to do the work yourself remember to check the
joints the proper way with leak detection fluid and pressure
testing.

Hardly pressure testing. I assume you mean soundness or hold-up check.

Indeed. A lack of preciseness on my part.


--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54

On Mon, 19 Mar 2007 09:08:43 +0000, Vass wrote:

"lawrie1" wrote in message
oups.com...
I am installing a gas hob and need to make a connection to an existing
gas copper gas pipe. Can I use a compression fitting to extend the
pipe to the hob, I was also going to puy a gas shut off tap in line as
well.The pipe pipe will be hidden behind a cooker, Can I use
compression fittings behind an appliance where access would not
normally be made or do I need to make a soldered connection first and
extend the pipe to the hob. I will of course use gas jointing
compound, what do you think about using gas PTFE tape on the thread as
well?

Gas cock is compression
but you really should be getting CORGI to check it and commission
the hob.

Clearly the OP question shows they are not yet up to the experience level
require for this work.

Compression joints are acceptable, the cut-off is mandatory.
Gas (or water) PTFE tape is not welcome on the threads of compression
anywhere except where the seal is made on the threads.




--
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
Choosing a Boiler FAQ http://www.makewrite.demon.co.uk/BoilerChoice.html
Gas Fitting Standards Docs he http://www.makewrite.demon.co.uk/GasFittingStandards

"David Hansen" wrote in message
...
On Mon, 19 Mar 2007 11:10:51 GMT someone who may be "Jim Alexander"
wrote this:-

If you do decide to do the work yourself remember to check the
joints the proper way with leak detection fluid and pressure
testing.

Hardly pressure testing. I assume you mean soundness or hold-up check.

Indeed. A lack of preciseness on my part.


--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54
Should you wish to even more precise then tightness test is the the term
used these days.