Gas leak?

[[29051]]

It might be worth considering that the stench used to make the gas smell can linger too. We spent a while last year tracing a 'gas leak' which turned out to be the screw-on carry handle which was inside the chart table for a few days while the spare bottle was being refilled. It reeked.

 

[saltylegs]

If all connections, seals and piping are gas tight it is still possible that gas can leak from the vent on the regulator when you turn the cylinder valve on.
On some regulators there is a limited relief built in to prevent over pressure down stream of the regulator.
As boat gas systems are of a very small volume when you turn on the cylinder you can get a large pressure rise in the system that should normally stop at about 50mbar but due to the small system volume this can quite often go higher.
Regulators that have a limited relief will blow of usually between 55 and 60mbar, the relief/vent should then close off again and the regulator will operate through the normal pressure range.
All regulators should have a label detailing outlet pressure, max inlet pressure and if they have a relief or over pressure shut off, those set pressures will also be noted.

 

[FullCircle]

http://www.birdtrader.co.uk/Canaries/A/passerine-for-sale.php

 

[VicS]

If all connections, seals and piping are gas tight it is still possible that gas can leak from the vent on the regulator when you turn the cylinder valve on.
On some regulators there is a limited relief built in to prevent over pressure down stream of the regulator.
As boat gas systems are of a very small volume when you turn on the cylinder you can get a large pressure rise in the system that should normally stop at about 50mbar but due to the small system volume this can quite often go higher.
Regulators that have a limited relief will blow of usually between 55 and 60mbar, the relief/vent should then close off again and the regulator will operate through the normal pressure range.
All regulators should have a label detailing outlet pressure, max inlet pressure and if they have a relief or over pressure shut off, those set pressures will also be noted.

Good points
Marine regulators ( BS EN 12864 Annexe M) certainly have this over pressure relief valve (set at 75mb ITYWF) As far as I know camping/caravanning regulators ( BS EN 1949) dont. Mine certainly does not. The Op has not said if he has the latest marine type or "merely" a caravan type

 

[VicS]

http://www.birdtrader.co.uk/Canaries/A/passerine-for-sale.php

Twit ... or should I say tweet ...... and I clicked the link

 

[dslittle]

When I open gas locker and turn on gas always get a whiff of gas, doesn't seem to last, got Alde bubble tester no bubbles, been over all the unions with bubble liquid, no bubbles, gas detector in bilge no alarm.

What should I do next?

Are they GOK fittings and a 4.5kg bottle? If so, is the connection to the bottle a 'notched' German fitting? I found out that the German fitting will happily screw onto the 4.5kg bottle but not make a good seal.

GOK provided (sold) an adapter to ensue a good seal. The original set-up came new with the boat in 2008!!!

 

[FullCircle]

Twit ... or should I say tweet ...... and I clicked the link

Charmed, I'm sure.

 

[saltylegs]

Good points
Marine regulators ( BS EN 12864 Annexe M) certainly have this over pressure relief valve (set at 75mb ITYWF) As far as I know camping/caravanning regulators ( BS EN 1949) dont. Mine certainly does not. The Op has not said if he has the latest marine type or "merely" a caravan type

Yip the over pressure shut off is usually set at 75mbar and the limited relief between 55 and 60mbar but all the info should be on the data label.

Edit. forgot to say the new caravan regulators can have this feature too.

 

[VicS]

Yip the over pressure shut off is usually set at 75mbar and the limited relief between 55 and 60mbar but all the info should be on the data label.

Edit. forgot to say the new caravan regulators can have this feature too.

Can you explain "over pressure shut off" and "limited relief".

All I have found is the requirement for a "75 mbar over-pressure relief valve" and mention of an "internal lock-up valve"

I find all this and the difficulty finding proper descriptions and explanations rather confusing.

I last renewed my regulator before I became aware of all the current marine standards and it is therefore just a "camping" type bought from the local camping shop. It is due for replacement pretty soon I think and I would like to understand a bit more about the requirements and specifications before buying a new "marine" regulator.

 

[hartcjhart]

where are you testing for the gas, it should be at the lowest possible point as the gas is heavier than air

 

[Vara]

http://www.birdtrader.co.uk/Canaries/A/passerine-for-sale.php

This could be the way forward, a nice breeding pair and convert cabin lights to Davey lamps.Job done.

Vic was right but I would've used a preceding vowel.

 

[Vara]

where are you testing for the gas, it should be at the lowest possible point as the gas is heavier than air

in OP, bilge was the clue.

 

[alahol2]

Yip the over pressure shut off is usually set at 75mbar and the limited relief between 55 and 60mbar but all the info should be on the data label.

Can anyone explain why you could possibly need an over pressure shut off and a relief valve? Is it in case the bottle is overfilled or maybe the bottle getting very hot? Is it in response to a series of related accidents or did someone just say 'That sounds like a good idea'?

 

[Vara]

The sequel,

New gas bottle, new regulator, gas locker free of all gaseous whiffs.

Replaced reg as it came with the boat so was uncertain as to age or history, flex tubing was replaced in Feb so felt flexing inspection sufficient.

Many thanks for everybody's input, useful for concentrating the mind on problem solving. (Exempt Full Circle and Ellesar of course, I'll sort you two out in the playground.)

 

[saltylegs]

Sorry been away a couple of days.

Regulators are generally now fitted with differing degrees of over pressure protection.
This is to protect downstream items such as the cooker where some of the fittings such as gas taps may have a maximum operating pressure (typically 50 to 100mbar)
typically when you turn on the gas cylinder the pressure can go over the normal range so some regulators are fitted with limited relief depending on regulator spec this can be between 55 and 75mbar as the pressure drops to the set point then the limited relief closes and all is hunky dory again.
Over pressure shut off or OPSO usually comes in when the limited relief does not pass enough gas and the pressure continues to climb to around 75 to 85mbar, this is normally due to a faulty regulator and is a slam shut that stops the flow off gas completely requiring manual reset.
there is also full relief (stop sniggering at the back) which continues to vent gas without any OPSO.

salty.