Overfilled Gaz cylinders

[Robin]

We left Poole on our hols with all four Gaz cylinders exchanged for full ones, only to find (after we left) that all 4 were overfilled. As a result there was excess pressure at the burners that blew out the flame far enough to miss the flame failure sensor so in effect the cooker wouldn't light. This is the 2nd time this has happened so we at least new we could vent off the excess (outside on the swim platform with the wind blowing away...) to get things going. We later bought a new regulator just in case ours was sensitive to a slight overpressure, but the result was the same. I didn't have a Corgi man fit the regulator, but didn't feel too guilty as the depot that supplied the faulty cylinders were the home based Corgi guys anyway. Ho Hum.

 

[StugeronSteve]

I exchanged an empty cylinder a couple of weeks ago, the new one, although fully charged, appeared to be blowing a very weak gas mix with litle or no flame that went out as soon as the source of ignition was removed. Thought I was just blowing air out of line for a start.

 

[Fr J Hackett]

I think the problem is likley to be one of regulated pressure, the logic being that the cylinders are filled to weight and the gas is liquified and only converts back to gas when the pressure causing the gas to be liquified is lowered ie you open the tap. With butane and propane this pressure is relativly low but still needs to be regulated, hence the external regulator. The pressure remains constant as long as their is liquified gas in the bottle. It is possible but highly unlikley that their was a significant amount of compressed air in the bottle which acted as a propellant. It is also possible but very unlikley that the gas in the bottle was propane and not butane, propane having a higher vapour pressure than butane. Does your cooker have an internal regulator which may have failed?Are the cookers burners OK ie are any partially blocked causing the others to flare, did all the burners behave as you describe?

 

[Robin]

That is exactly the symptoms we had. In fact is is overpressured gas that lights with a flame but not with the cooker's spark ignition, but the flame is 'blown' farther out from the burner and misses the flame failure sensor. In our case we vented off some each time we changed the cylinder but once I didn't let enough out as it was still no quite right, turning on the 2nd burner for a few minutes helped and it eventually settled down.

 

[StugeronSteve]

My thoughts were that the cylinder had been charged with compressed air as there was no significant gas smell when the burners failed to light. My gas detector head, which is immediately below the grill and very sensitive, also failed to detect anything.

 

[Robin]

The cooker is only 5 years old, a Force 10 that will run on propane or butane. As I said we bought a new regulator in case ours was over sensitive to slightly higher pressure but there was no difference. The effect was the same on all burners and we tried each cylinder in turn and all behaved the same, but once we let out a few seconds of vented gas (screwdriver in the valve) all was then OK.

 

[Steve_N]

Had exactly the same symptoms with the cylinder before last: the flame blown too far from burner to keep alight. As you say, once a little gas is vented all returns to normal. The last cylinder was OK - it must be an overfilling problem as you suspect.

 

[Talbot]

Change over to calor, but keep a single calor gaz for trips to France etc.

 

[mikejames]

I believe there is sometimes some air in the cylinders which comes out before the butane with a new cylinder. I have had this with the flame burning with a rougher sound before settling down.
That was before I retired the boat gas stove to beocme an open-air camping stove.

 

[Robin]

I think I will change the system to have a wall manifold with 2 Calor with a changeover valve and two spare Gaz fitted with Gaz to Calor adapter. We have the space and I still have a spare Calor cylinder at home plus the propane Calor one we use for the boat BBQ could be swapped for another as the BBQ will run on butane OK anyway. I'm tired of paying double the price for the same gas from the same depot just because it is in the Gaz bottle not the Calor one.

 

[Anchorite]

Re: Overfilled Gaz cylinders (and half empty cartridges)

Not sure it's to do with "overfilled" cylinders: I've often seen the same problem on cartridges on a Camping Gaz blowlamp....and I've always thought it was linked to shaking up the cartridge (unintentionally), as it can happen with a half-full cartridge. A blowlamp setup has however no pressure regulator, and this appliance (the reg) on a cooker setup should give the same pressure more-or-less regardless of the upstream pressure (which changes quite a lot as the air temperature changes: 1.5 bars in the cylinder at 15° rises to 3.2 at 30° C...or from 22 psi to about 45...and no difference in the burner rates. This is for Butane (CGaz).

 

[toad]

I also recall reading somewhere that a head of air is sometimes present in newly filled cylinders and needs venting off.

 

[Sheff]

Sorry to say that your problem is more likely to be UNDERfilled cylinders with a slug of air in the top.

What you're experiencing is similar to trying to light a blowtorch without blocking out the air first, i.e. too much air and not enough gas.

Your regulator (unless faulty) will give a reasonably constant outlet pressure whether there is say, 4 Bar or 1 Bar cylinder pressure.

Hope that makes sense,
Paul.

 

[steve_cronin]

Re: Overfilled Gaz cylinders (and half empty cartridges)

[ QUOTE ]
A blowlamp setup has however no pressure regulator,

[/ QUOTE ]

Actually, they have a primitive pressure regulator in the form of a passage tightly filled with a bunch of tightly packed brass rods which operate on an osmotic principle to restrict pressure by stifling flow.

Steve Cronin

 

[Robin]

Re: Overfilled Gaz cylinders UPDATE

I just had a call from the Calor Centre who confirmed that there was a bad batch of cylinders sent out and they have had several back. The comment was they were overfilled and this happens sometimes, but it was AIR that I vented off, they didn't seem to think it was a serious safety issue either but I didn't find that very reassuring. Apparently it does happen occasionally with the 4.5kg Calor cylinders as well but I must say I never had that problem with Calor, only the 907 Gaz.

 

[Anchorite]

Re: Ultracrepidation!

Oi! That's my field! Don't confuse a variable restriction with a limiting orifice (you could fool someone...) /forums/images/graemlins/wink.gif

 

[StugeronSteve]

Re: Overfilled Gaz cylinders UPDATE

That would explain my problem then. All I can say is there must have been a lot of air in the cylinder I had! Never known this before, so it can't be all that common.

 

[steve_cronin]

Didn\'t mention....

..."variable" at all. Did I?

I suspect that my description of the device is much more help to the layman than having trade jargon spouted at him.

But then SOME trades RELY upon jargon to preserve the mystique AND their over-inflated incomes, don't they?

Steve Cronin

 

[Momac]

I know this is a very old thread but it did help me to solve the same issue of the gas from the new Campingaz 907 cylinder not igniting. By venting off some of the gas from the cylinder this seems to have helped .
The problem seems now resolved.
At last I have my cup of tea.
Thankfully we had earlier completed cooking of our meal on the last of the gas from the previous cylinder.

 

[Stemar]

I'd be very leery of poking that valve.

Many years ago, my uncle was camping, back when Camping Gaz was the latest thing, and he got a bottle that needed to be vented before it would work. He did it once too often, and the ball valve shot out, closely followed by the contents of the bottle. Fortunately, no one was smoking at the time, and the gas dissipated safely, but a frame tent full of gas going up would have been about as enjoyable as a boat full of gas going up.