Hello,

We've just bought a flat that has a gas cooker and gas heaters (these
have not been used for 2 years).
I tried to light the cooker yesterday, the gas is turned on and is
making a noise from the one ring on the hob i tried, but this flow of
gas blows out anything I try to light it with (lighter, matches etc).

We plan to get the heaters checked out before use, but I assumed I
could light the cooker.

Could this be air in the pipes?

I only tried to light the cooker for about 2 minutes and I got a bit
paranoid that I'd blow myself and the neigbours up

Any ideas?

cheers

-- t.

"twinkle twinkle" wrote in message
.com...
Hello,

We've just bought a flat that has a gas cooker and gas heaters (these have
not been used for 2 years).
I tried to light the cooker yesterday, the gas is turned on and is making
a noise from the one ring on the hob i tried, but this flow of gas blows
out anything I try to light it with (lighter, matches etc).

We plan to get the heaters checked out before use, but I assumed I could
light the cooker.

Could this be air in the pipes?

I only tried to light the cooker for about 2 minutes and I got a bit
paranoid that I'd blow myself and the neigbours up

Any ideas?

cheers

-- t.



Get a corgi registered engineer in asap
--
the_constructor

Don't tip it, recycle it. Join your local group.

http://freecycle.org/display.php?reg...ited%20Kingdom

On 2007-12-23 08:51:28 +0100, "the_constructor"
said:


"twinkle twinkle" wrote in message
.com...
Hello,

We've just bought a flat that has a gas cooker and gas heaters (these have
not been used for 2 years).
I tried to light the cooker yesterday, the gas is turned on and is making
a noise from the one ring on the hob i tried, but this flow of gas blows
out anything I try to light it with (lighter, matches etc).

We plan to get the heaters checked out before use, but I assumed I could
light the cooker.

Could this be air in the pipes?



Get a corgi registered engineer in asap

The flat isn't in the UK so it won't be a CORGI engineer, but as I
mentioned I'll be getting an engineer to look at it (in the New Year).

Anyone know of a safe way to try to get the cooker lit?

The previous owner was at the place trying to light the heaters
yesterday, but I stopped her as something wasn't right and I don't want
to light the heaters until they have been checked out, but she was
furiously clicking away at the ignition switch of the heater, so I
turned off the gas.

The gas that was coming out of the cooker was extinguishing the flame
from the matches and lighter so I assumed there is air in the pipes
doing this, but I didn't want to leave the cooker on any longer until I
checked out exactly what to do.

What is the usual method used for clearing the pipes?

-- t.

On Sun, 23 Dec 2007 09:28:15 +0100, twinkle twinkle wrote:

What is the usual method used for clearing the pipes?

Turn on an appliance an let the gas force the air out...

When you turn a gas appliance on is there a smell of gas? Is there any
attempt at a flame post your ignition implement? Have you tried not having
your ignition implement not in direct line of the gas flow but slightly
below it? Have you tried lighting without the burning being full on?

As the pipes are remaining pressurised they must still be connected to a
supply of pressure. I find it highly unlikely that this is going to be
anything other than the gas supply. The pressure regulator might have
failed but I would half expect them to fail safe, ie off rather than let
the full supply pressure through. Is there a "hard" or "gentle" hiss when
you open a valve?

--
Cheers
Dave. pam is missing e-mail

twinkle twinkle wrote:
On 2007-12-23 08:51:28 +0100, "the_constructor"
said:


"twinkle twinkle" wrote in message
.com...
Hello,

We've just bought a flat that has a gas cooker and gas heaters (these
have
not been used for 2 years).
I tried to light the cooker yesterday, the gas is turned on and is
making
a noise from the one ring on the hob i tried, but this flow of gas blows
out anything I try to light it with (lighter, matches etc).

We plan to get the heaters checked out before use, but I assumed I could
light the cooker.

Could this be air in the pipes?



Get a corgi registered engineer in asap

The flat isn't in the UK so it won't be a CORGI engineer, but as I
mentioned I'll be getting an engineer to look at it (in the New Year).

Anyone know of a safe way to try to get the cooker lit?

The previous owner was at the place trying to light the heaters
yesterday, but I stopped her as something wasn't right and I don't want
to light the heaters until they have been checked out, but she was
furiously clicking away at the ignition switch of the heater, so I
turned off the gas.

The gas that was coming out of the cooker was extinguishing the flame
from the matches and lighter so I assumed there is air in the pipes
doing this, but I didn't want to leave the cooker on any longer until I
checked out exactly what to do.

What is the usual method used for clearing the pipes?


Turn em on an open the windows in a breeze.

Gas burns in air. Too much or too little air and it won't.Safest is too
much.

-- t.

On 23/12/2007 09:48, The Natural Philosopher wrote:

twinkle twinkle wrote:
On 2007-12-23 08:51:28 +0100, "the_constructor"
said:

What is the usual method used for clearing the pipes?

Turn em on an open the windows in a breeze.
Gas burns in air. Too much or too little air and it won't.

With between 5% and 15% gas the mixture explodes.

Andy Burns wrote:
On 23/12/2007 09:48, The Natural Philosopher wrote:

twinkle twinkle wrote:
On 2007-12-23 08:51:28 +0100, "the_constructor"
said:

What is the usual method used for clearing the pipes?

Turn em on an open the windows in a breeze.
Gas burns in air. Too much or too little air and it won't.

With between 5% and 15% gas the mixture explodes.

Exactly.

So the danger is above 20% when you open the window...


Open the window first.

On Sun, 23 Dec 2007 10:09:36 +0000, Andy Burns wrote:

Gas burns in air. Too much or too little air and it won't.

With between 5% and 15% gas the mixture explodes.

True but not without a source of ignition, it doesn't do it spontaneously.
Hence venting pipes with the windows open, you are not likely to get
anywhere near the lower concentration limit.

--
Cheers
Dave. pam is missing e-mail

In an earlier contribution to this discussion,
twinkle twinkle wrote:

Hello,

We've just bought a flat that has a gas cooker and gas heaters (these
have not been used for 2 years).
I tried to light the cooker yesterday, the gas is turned on and is
making a noise from the one ring on the hob i tried, but this flow of
gas blows out anything I try to light it with (lighter, matches etc).

We plan to get the heaters checked out before use, but I assumed I
could light the cooker.

Could this be air in the pipes?

I only tried to light the cooker for about 2 minutes and I got a bit
paranoid that I'd blow myself and the neigbours up

Any ideas?

cheers

-- t.

You've obviously got air rather than gas coming out of the nozzle! You need
a decent flow of gas to clear the air out of the pipes. This may not be
possible with everything connected, because there is probably a flame
failure device in the cooker which only allows a trickle of gas until the
pilot is lit - so you have a vicious circle.

Try this:
Gas off at the meter
Disconnect gas pipe where it enters cooker
Open doors and windows
Gas on at meter until gas rather than air comes out of the pipe
Gas off at meter
Reconnect pipe to cooker
Gas on at meter
Check with washing-up liquid that re-connected joint isn't leaking
Wait a few minutes for gas in room to disperse
Light cooker!

Using common sense and plenty of ventilation, you're very unlikely to end up
with an explosive mixture of gas in the room. A professional would do
exactly what I've described above - there's no other way to purge the pipes
when a flame failure device is present.

If there *isn't* a flame failure device - i.e. if there's a good flow of
(air) from the hob rings, turn all rings full on for a couple of minutes -
or until you can smell neat gas coming out - with the doors and windows
open. Then allow time for the gas to disperse and have another go at
lighting it.
--
Cheers,
Roger
______
Email address maintained for newsgroup use only, and not regularly
monitored.. Messages sent to it may not be read for several weeks.
PLEASE REPLY TO NEWSGROUP!

Dave Liquorice wrote:

As the pipes are remaining pressurised they must still be connected to a
supply of pressure. I find it highly unlikely that this is going to be
anything other than the gas supply. The pressure regulator might have
failed but I would half expect them to fail safe, ie off rather than let
the full supply pressure through.

When I had to call for work on my boiler [PCB :-( ] it was
discovered that my gas pressure was roughly twice what it should
have been. Got the regulator changed within the hour.

Chris
--
Chris J Dixon Nottingham UK


Have dancing shoes, will ceilidh.

Roger Mills wrote:

Try this:
[...]
Check with washing-up liquid that re-connected joint isn't leaking

The use of washing-up liquid for gas soundness testing is very strongly
deprecated since the salt content can lead to corrosion, eventually
causing leakage. A proprietary gas leak detection spray (available from
Screwfix) should be used.

For reference the full formal gas purging procedure can be found he
http://groups.google.co.uk/group/uk....e?dmode=source

--
Andy

In message , Roger Mills
writes
Using common sense and plenty of ventilation, you're very unlikely to end up
with an explosive mixture of gas in the room.

The definition of "unlikely" being?

I have a jar with 1000 jelly babies in it, 1 of them has cyanide in it.
Would you like a jelly baby from my jar?
You are unlikely to get the poisoned one.

--
Bill

On Sun, 23 Dec 2007 09:28:15 +0100, twinkle twinkle wrote:

On 2007-12-23 08:51:28 +0100, "the_constructor"
said:


"twinkle twinkle" wrote in message
.com...
Hello,

We've just bought a flat that has a gas cooker and gas heaters (these
have not been used for 2 years).
I tried to light the cooker yesterday, the gas is turned on and is
making a noise from the one ring on the hob i tried, but this flow of
gas blows out anything I try to light it with (lighter, matches etc).

We plan to get the heaters checked out before use, but I assumed I
could light the cooker.

Could this be air in the pipes?



Get a corgi registered engineer in asap

The flat isn't in the UK so it won't be a CORGI engineer, but as I
mentioned I'll be getting an engineer to look at it (in the New Year).

Anyone know of a safe way to try to get the cooker lit?

The previous owner was at the place trying to light the heaters
yesterday, but I stopped her as something wasn't right and I don't want
to light the heaters until they have been checked out, but she was
furiously clicking away at the ignition switch of the heater, so I
turned off the gas.

The gas that was coming out of the cooker was extinguishing the flame
from the matches and lighter so I assumed there is air in the pipes
doing this, but I didn't want to leave the cooker on any longer until I
checked out exactly what to do.

What is the usual method used for clearing the pipes?

FYI only look at the gas fitting FAQ.
However you should leave checking over of an unused system to someone
with enough experience.


--
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

In article ,
"Roger Mills" writes:
You've obviously got air rather than gas coming out of the nozzle! You need
a decent flow of gas to clear the air out of the pipes. This may not be
possible with everything connected, because there is probably a flame
failure device in the cooker which only allows a trickle of gas until the
pilot is lit - so you have a vicious circle.

Try this:
Gas off at the meter
Disconnect gas pipe where it enters cooker
Open doors and windows
Gas on at meter until gas rather than air comes out of the pipe

In some countries (France being one), this will likely cause
the gas supply to trip off, and you won't be able to reset it.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

twinkle twinkle wrote:
Hello,

We've just bought a flat that has a gas cooker and gas heaters (these
have not been used for 2 years).
I tried to light the cooker yesterday, the gas is turned on and is
making a noise from the one ring on the hob i tried, but this flow of
gas blows out anything I try to light it with (lighter, matches etc).


The gas in the main pipe to the house has gone off and lost all its
flammability because it's been sitting in the pipe for 2 years. You'll have
to ask the engineer to rejuvinate the gas in the pipe under the street with
a FreshGas tablet otherwise it'll take hours to flush out all the expired
gas because the main pipe is very big, and that'll cost you a fortune.

HTH

Si

In some countries (France being one), this will likely cause
the gas supply to trip off, and you won't be able to reset it.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]


That sounds interesting - is there some sort of cut-off device that shuts
off if the flow exceeds a certain volume?

This could be a life saver in areas where the theft of pipes is becoming
common place.

Bill wrote:
In message , Roger Mills
writes
Using common sense and plenty of ventilation, you're very unlikely
to end up with an explosive mixture of gas in the room.

The definition of "unlikely" being?

I have a jar with 1000 jelly babies in it, 1 of them has cyanide in
it. Would you like a jelly baby from my jar?
You are unlikely to get the poisoned one.

Zactly.

Our grill started playing up: on the low setting it lights and burns ok, if
I turn the gas up even slightly, or light it and leave it on full, there's a
bang that shakes the floors in the house and it blows itself out! Much fun
with just a tiny amount of gas. At first I thought it was the gammon steaks
I was cooking going pop until I realised that the 'pop' made the doors
rattle.

We're not using it now )

Si

"Mungo "Two Sheds" Toadfoot" wrote in message
...
twinkle twinkle wrote:
Hello,

We've just bought a flat that has a gas cooker and gas heaters (these
have not been used for 2 years).
I tried to light the cooker yesterday, the gas is turned on and is
making a noise from the one ring on the hob i tried, but this flow of
gas blows out anything I try to light it with (lighter, matches etc).


The gas in the main pipe to the house has gone off and lost all its
flammability because it's been sitting in the pipe for 2 years. You'll
have to ask the engineer to rejuvinate the gas in the pipe under the
street with a FreshGas tablet otherwise it'll take hours to flush out all
the expired gas because the main pipe is very big, and that'll cost you a
fortune.

HTH

Si

Will the "flammability" have condensed and be sitting in a highly volatile
pool at a low point in the system?

(tongue in cheek)

John wrote:

Will the "flammability" have condensed and be sitting in a highly
volatile pool at a low point in the system?


How do you think they make petrol? Tch!

Si

John wrote:
"Mungo "Two Sheds" Toadfoot" wrote in message
...
twinkle twinkle wrote:
Hello,

We've just bought a flat that has a gas cooker and gas heaters (these
have not been used for 2 years).
I tried to light the cooker yesterday, the gas is turned on and is
making a noise from the one ring on the hob i tried, but this flow of
gas blows out anything I try to light it with (lighter, matches etc).

The gas in the main pipe to the house has gone off and lost all its
flammability because it's been sitting in the pipe for 2 years. You'll
have to ask the engineer to rejuvinate the gas in the pipe under the
street with a FreshGas tablet otherwise it'll take hours to flush out all
the expired gas because the main pipe is very big, and that'll cost you a
fortune.

HTH

Si

Will the "flammability" have condensed and be sitting in a highly volatile
pool at a low point in the system?


I am just trying to work out what happened to all that natural fgas
under the North sea, that has been there for a few million years,.

Of course. The flammability has pooled at the bottom and soaked its way
to Saudi Arabia.

Its all so simple when you work it out!



(tongue in cheek)

In an earlier contribution to this discussion,
Andy Wade wrote:

Roger Mills wrote:

Try this:
[...]
Check with washing-up liquid that re-connected joint isn't leaking

The use of washing-up liquid for gas soundness testing is very
strongly deprecated since the salt content can lead to corrosion,
eventually causing leakage. A proprietary gas leak detection spray
(available from Screwfix) should be used.


Not ideal, I agree, but the OP isn't in the UK (near Screwfix) and is
virtually certain *not* to have the proper stuff to hand.

--
Cheers,
Roger
______
Email address maintained for newsgroup use only, and not regularly
monitored.. Messages sent to it may not be read for several weeks.
PLEASE REPLY TO NEWSGROUP!

In an earlier contribution to this discussion,
Andy Wade wrote:


For reference the full formal gas purging procedure can be found he
http://groups.google.co.uk/group/uk....e?dmode=source

Hm - makes interesting reading! I've never seen any of the 'professionals'
working on my mas installation get anywhere near following all that!
--
Cheers,
Roger
______
Email address maintained for newsgroup use only, and not regularly
monitored.. Messages sent to it may not be read for several weeks.
PLEASE REPLY TO NEWSGROUP!

In article ,
"John" writes:
In some countries (France being one), this will likely cause
the gas supply to trip off, and you won't be able to reset it.

That sounds interesting - is there some sort of cut-off device that shuts
off if the flow exceeds a certain volume?

It's built in to all gas cocks in France (at least, I think
you are required to use gas cocks with it built in). It's
also built in to the main regulator in at least some cases
(you can't reset that one).

This could be a life saver in areas where the theft of pipes is becoming
common place.

It way predates that. I suspect it's to cope with appliances
falling off the wall, or buildings collapsing, or some such,
leaving a ripped open full bore gas pipe.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

On Sun, 23 Dec 2007 16:20:47 +0000, Roger Mills wrote:

In an earlier contribution to this discussion, Andy Wade
wrote:


For reference the full formal gas purging procedure can be found he
http://groups.google.co.uk/group/uk....c770797eeda2e?
dmode=source

Hm - makes interesting reading! I've never seen any of the
'professionals' working on my mas installation get anywhere near
following all that!

Well I confess that if I'm fitting a modern boiler I'll probably skip the
purge step as there is no chance that a flame could propagate back
through the premix fan and zero governor gas valve back into a
combustible mix in the pipes.

If I'm fitting a gas fire, say, I'd have to wait a very very long time
for the gas to come through via the pilot hole. In these circumstances
it's a lot quicker to open the pipework. In which case you need to make
sure enough gas and not too much gas comes through. OK, there's another
short cut, the timbre of the hissing changes between air and gas.

--
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

On Sun, 23 Dec 2007 13:58:40 +0000, John wrote:


In some countries (France being one), this will likely cause the gas
supply to trip off, and you won't be able to reset it.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]


That sounds interesting - is there some sort of cut-off device that
shuts off if the flow exceeds a certain volume?

This could be a life saver in areas where the theft of pipes is becoming
common place.

Indeed so. Most pre-pay key meters have all sorts of abuse trips.


--
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

Chris J Dixon wrote:

When I had to call for work on my boiler [PCB :-( ] it was
discovered that my gas pressure was roughly twice what it should
have been. Got the regulator changed within the hour.

Chris

Being a cynic I wonder if that was because they thought you weren't safe
- or because as gas is measured by volume you were getting twice the
amount of gas you were paying for?

Andy

Andy Champ wrote:

Being a cynic I wonder if that was because they thought you weren't safe
- or because as gas is measured by volume you were getting twice the
amount of gas you were paying for?

Err, doubling the gauge pressure from 20 to 40 mb (over atmospheric
pressure of ~1000 mb) would only increase the volume of gas delivered by
~2%. To double the volume, the gauge pressure would have to rise to
around 1 bar, at which point things would get a little dangerous, as the
residents of (was it) Hemel Hempstead (?) once found out.

--
Andy

On 2007-12-23 17:32:49 +0000, (Andrew
Gabriel) said:

In article ,
"John" writes:
In some countries (France being one), this will likely cause
the gas supply to trip off, and you won't be able to reset it.

That sounds interesting - is there some sort of cut-off device that shuts
off if the flow exceeds a certain volume?

It's built in to all gas cocks in France (at least, I think
you are required to use gas cocks with it built in). It's
also built in to the main regulator in at least some cases
(you can't reset that one).

This could be a life saver in areas where the theft of pipes is becoming
common place.

It way predates that. I suspect it's to cope with appliances
falling off the wall, or buildings collapsing, or some such,
leaving a ripped open full bore gas pipe.

I saw an interesting installation when passing a house in Bucharest in
a taxi recently (there was a traffic jam).

The house was set back from the road some 5-6 metres and there was a
front wall of about 1.5 metres in height.

The gas pipe (looked like yellow painted steel) came up out of a hole
in the pavement next to the wall and then horizontally across the
garden at 1.5m above the ground. It wasn't clipped to the wall but
just rested on top of it.

The meter was suspended from the pipe at a position mid way across the
garden and was supported by a couple of bits of wood stuffed into the
ground. The pipe continued through a hole in the front wall of the
house. Of course, the hole had not been made good. Oh, and the stop
tap was on the house side of the meter.

This appeared to have been there for years judging by the appearance
and certainly was not a temporary arrangement.

In article ,
Andy Wade writes:
Andy Champ wrote:

Being a cynic I wonder if that was because they thought you weren't safe
- or because as gas is measured by volume you were getting twice the
amount of gas you were paying for?

It's one of the specific incidents they have to respond to
in a short time (hours).

Err, doubling the gauge pressure from 20 to 40 mb (over atmospheric
pressure of ~1000 mb) would only increase the volume of gas delivered by
~2%. To double the volume, the gauge pressure would have to rise to
around 1 bar, at which point things would get a little dangerous, as the
residents of (was it) Hemel Hempstead (?) once found out.

It was Royston where the gas company connected a high pressure
gas trunk network supply to the low pressure local supply network
and instantly destroyed a very large number of gas meters,
appliances, regulators, etc.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

Andrew Gabriel wrote:

It was Royston where the gas company connected a high pressure
gas trunk network supply to the low pressure local supply network
and instantly destroyed a very large number of gas meters,
appliances, regulators, etc.

Yes, you're right, it was Royston, in March 1991:
http://www.co-ordination.gov.uk/uplo.../appendixa.pdf

Item 3 refers to 56 explosions being caused.

--
Andy

Andy Wade wrote:
Andy Champ wrote:

Being a cynic I wonder if that was because they thought you weren't
safe - or because as gas is measured by volume you were getting twice
the amount of gas you were paying for?

Err, doubling the gauge pressure from 20 to 40 mb (over atmospheric
pressure of ~1000 mb) would only increase the volume of gas delivered by
~2%. To double the volume, the gauge pressure would have to rise to
around 1 bar, at which point things would get a little dangerous, as the
residents of (was it) Hemel Hempstead (?) once found out.

Ah! A Gasman's double isn't a physicist's double. I stand corrected.

Andy

On Mon, 24 Dec 2007 22:13:56 +0000, Andy Champ wrote:

Andy Wade wrote:
Andy Champ wrote:

Being a cynic I wonder if that was because they thought you weren't
safe - or because as gas is measured by volume you were getting twice
the amount of gas you were paying for?

Err, doubling the gauge pressure from 20 to 40 mb (over atmospheric
pressure of ~1000 mb) would only increase the volume of gas delivered
by ~2%. To double the volume, the gauge pressure would have to rise to
around 1 bar, at which point things would get a little dangerous, as
the residents of (was it) Hemel Hempstead (?) once found out.

Ah! A Gasman's double isn't a physicist's double. I stand corrected.

Yes, indeed so. Whenever 'pressure' is referred to in gas, plumbing,
heating etc. It is a synonym for Gauge Pressure.



--
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