Can a propane camp stove be safe on a boat?

[Reefmagnet]

Originally Posted by weavis

I have a fitted stove on my Centaur, but sometimes its easier to use portable BUTANE cylinder burners. Now..... I use it on top of the gimballed oven AND have then strapped to the cooker with jubilee clips. The hatch is open when cooking and so are vents. Ive done this on various boats for a lot of years.

I have guards for pans so nothing moves. I regularly check for heat under the burner and never leave it unattended. I only ever use it on the gimbal when the boat is underway and Ive run out of propane for the oven. There is no gas smell and the BUTANE bottles are self sealing when ejected from the connection to the burner. I usually carry 6-8 bottles of butane in the Gas locker in a box. Butane stinks if it leaks and Ive never ever smelled it.

They're the stoves that are being banned in parts of Australia (and the ban will no doubt spread to all of Oz). Not that they are inherently dangerous, but it was found in testing that a pressure release valve that is supposed to vent the canister if it overheats doesn't work in 84% of most stoves sold. When coupled with misuse that allows the canister to overheat (e.g. BBQ plates, big pans etc deflecting heat towards the canister) - KA-Booooooom!

[weavis]

Originally Posted by Reefmagnet

They're the stoves that are being banned in parts of Australia (and the ban will no doubt spread to all of Oz). Not that they are inherently dangerous, but it was found in testing that a pressure release valve that is supposed to vent the canister if it overheats doesn't work in 84% of most stoves sold. When coupled with misuse that allows the canister to overheat (e.g. BBQ plates, big pans etc deflecting heat towards the canister) - KA-Booooooom!

I think you will find that ALL of the problems in EVERY case was when the stove was misused.

My pans and gas kettle are the right size.

[Reefmagnet]

Originally Posted by weavis

I think you will find that ALL of the problems in EVERY case was when the stove was misused.

My pans and gas kettle are the right size.

Yes indeed. All injuries and the one death caused by exploding canisters in multiple instances were caused when the stove was being misused. Didn't stop the Nannies from moving in, however.

[delmarrey]

Originally Posted by Bulawayo

Hi Ron, These same people also write so much legislation that they made many of us run off to sea to get away from all the PC.
Unfortunately, they have a way of coercing many people to believe that all their diatribe is actually critical when its not. Recall reading about having a person walking in front of the early motor car carrying a red flag as the vehicles were so dangerous? My wife never leaves the cooker unattended unless its flat calm and we also have sniffers in the bilges. There is nothing wrong with using a camp stove within the boat as long as a few sensible precautions are taken. Typically, you could place the stove inside your stainless steel sink. You can, pretty easily, make up a multiway gimbal. You could knock up a six sided folding steel box.....but at the end of the day its how you use anything on your boat that creates the danger or safety. Most of us keep cans of petrol on our boats - the next bit of legislation shall be that you must not, and then the insurance companies shall have another excuse not to pay out despite the actual causes.
That also means that if someone is using a camp stove they must be aware of the insurance implications. As has already been pointed out many a barbeque is plumbed into the main gas cylinder, sometimes with lengthy gas lines. These hoses can also fail and that is why solenoids are a good idea, but we really do not need to get overly paranoid. Use a camp stove by all means - just lets be careful about how.

I'm not saying..........
let's go kill all the stupid people. But let's remove all the warning labels and and safety devices and let the problem work itself out.

[0urh]

Originally Posted by Reefmagnet

Yes indeed. All injuries and the one death caused by exploding canisters in multiple instances were caused when the stove was being misused. Didn't stop the Nannies from moving in, however.

Yes, in Queensland at Bunnings the other day could not buy a stove (taken off shelves) but can still buy the canisters?? Why is this?

[Wotname]

Originally Posted by 0urh

Yes, in Queensland at Bunnings the other day could not buy a stove (taken off shelves) but can still buy the canisters?? Why is this?

Could be for lots of reasons but I guessing they have a lot canisters in stock that need selling and the recall is only for the stove so they will only get reimbursed for the stoves.

The resellers arent too concerned about what happens when you use the gas but they are concerned with abiding by the gov. regulations. IMO.

[Reefmagnet]

Originally Posted by 0urh

Yes, in Queensland at Bunnings the other day could not buy a stove (taken off shelves) but can still buy the canisters?? Why is this?

I actually asked someone at Bunnings this very question just the other day (when stocking up on gas canisters!). The answer is that Bunnings intends to restock them again once they source stoves that can pass testing and requirements. The current blanket ban is only on the sale of new stoves that in general failed testing, not the usage of same (go figure!). In defense, I guess, 84% failure rate of a compulsory safety feature was pretty good justification for the ban although it doesn't really address the problem of people blowing themselves up.

[Ukeluthier]

Originally Posted by skipmac

If the gas canister starts leaking the pressure inside the plastic bottle will quickly reach the pressure of the gas canister and the seals will not work, again unless they are rated for full pressure which I doubt from your description.

Not so... unless the storage bottle is exactly the same interior volume as the cannister -- in which case the cannister would not fit. If the bottle is somewhat larger, the equilibrium pressure will be somewhat lower than that in the cannister. If the bottle is considerably larger, the pressure in the bottle could be relatively low.

I'm not arguing that this is a safe storage method... simply pointing out the error of your logic.

I'll take an ABYC-compliant propane system with a marine stove with a flame-failure device over a camp stove any day.

[Reefmagnet]

Originally Posted by Ukeluthier

Not so... unless the storage bottle is exactly the same interior volume as the cannister -- in which case the cannister would not fit. If the bottle is somewhat larger, the equilibrium pressure will be somewhat lower than that in the cannister. If the bottle is considerably larger, the pressure in the bottle could be relatively low.

I'm not arguing that this is a safe storage method... simply pointing out the error of your logic.

I'll take an ABYC-compliant propane system with a marine stove with a flame-failure device over a camp stove any day.

Actually, what you're saying works for compressed gas such as in a SCUBA tank. LPG is actually stored as liquid that turns to gas (boils) at pressures lower than around 100 psi. In this case it would exhibit a constant pressure whilst ever liquid was present. To demonstrate this, take a small can of water and place it in a large sealed container. Heat the container so the water boils then see what happens after a while. (WARNING: stand well clear and behind a safety screen)

[Don C L]

So as near as I can tell, the only difference in safety eqipment, on the marine stove itself is the automatic flame-out gas shut-off thermocouple which camp stoves and old RV stoves do not have. Is that right?

[Ukeluthier]

Originally Posted by Reefmagnet

Actually, what you're saying works for compressed gas such as in a SCUBA tank. LPG is actually stored as liquid that turns to gas (boils) at pressures lower than around 100 psi. In this case it would exhibit a constant pressure whilst ever liquid was present. To demonstrate this, take a small can of water and place it in a large sealed container. Heat the container so the water boils then see what happens after a while. (WARNING: stand well clear and behind a safety screen)

Point taken.

I agree that the equilibrium pressure would be the same unless the storage container was sufficiently large to allow all the liquid to gassify, and that would likely have to be pretty big.

My apologies to SkipMac.

[skipmac]

Originally Posted by Ukeluthier

Not so... unless the storage bottle is exactly the same interior volume as the cannister -- in which case the cannister would not fit. If the bottle is somewhat larger, the equilibrium pressure will be somewhat lower than that in the cannister. If the bottle is considerably larger, the pressure in the bottle could be relatively low.

I'm not arguing that this is a safe storage method... simply pointing out the error of your logic.

I'll take an ABYC-compliant propane system with a marine stove with a flame-failure device over a camp stove any day.

I wasn't trying to get technical on the pressure balance between the propane canister and the storage container but only point out that the potential safety issue but as I would understand it....

If you store a propane cylinder inside another container and the propane cylinder leaks then the container holding the propane cylinder will become pressurized and unless that container is pressure rated it will leak and thus will not be a safe way to store the propane cylinder.


I can see a couple of possible outcomes.

1. The external container leaks when the pressure of the leaking propane into the container reaches the psi that initiates the leak. In that case, if the propane canister leak is a slow one then the pressure in the propane cylinder will slowly decrease while the pressure in the container will stay more or less stable at the leak pressure until the propane has leaked out of the canister. At that point the pressure in the container and the canister will reach an equilibrium at some low pressure point.

This assumes that the leak from the storage container is a small, constant leak that doesn't blow a seal or o-ring or crack the container itself. If one of these occurs then the pressure in the container will be more or less ambient as the propane leaks out of the canister until again the system reaches an equilibrium but at this time at more or less ambient pressure.

2. The seal in the storage container doesn't blow so at some point the pressure in the container will reach an equilibrium point with the pressure in the propane cylinder which of course will be at a lower pressure than the initial pressure in the propane cylinder. At this time the propane will stop flowing out of the canister but if the hole in the canister is large enough there will be some exchange of gases between the container and the canister but the pressure will remain constant.



All this of course is impacted by the phase change from liquid to gas of the propane and that pressure limit.

But the whole point was, a plastic bottle unless it is a pressure rated container designed for the purpose is not a safe way to store propane if kept inside a boat because the propane could leak into the bilges and go boom. Even if the container was pressure rated I wouldn't use it to store propane below decks.

In an externally vented locker then a non pressure rated bottle may keep the propane cylinder drier and slow down corrosion so could be of some benefit.

[Ukeluthier]

SkipMac, your analysis is spot on.

I must have had a senior moment when I challenged your earlier statement. I neglected the fact that propane and butane are stored as liquids (LPG... Liquid Propane Gas... DUH! ). My comment might have had some merit for CNG, but I agree that trying to store gas canisters in non-pressure-rated containers is unlikely to have any benefit other than protecting them from corrosion.

[Reefmagnet]

Originally Posted by Don C L

So as near as I can tell, the only difference in safety eqipment, on the marine stove itself is the automatic flame-out gas shut-off thermocouple which camp stoves and old RV stoves do not have. Is that right?

A specialist marine stove may also have more stainless steel in it's construction and will usually include a gimball mount and pot retainers which could arguably be classified as "safety" equipment.

[jkindredpdx]

Originally Posted by Don C L

So as near as I can tell, the only difference in safety eqipment, on the marine stove itself is the automatic flame-out gas shut-off thermocouple which camp stoves and old RV stoves do not have. Is that right?

Can't say what everyone has, but...

1. my ENO stove and oven from 1974 has the thermo sensors that shut off gas to the burner if there is inadequate heat. Last week I had the tea pot on low and the breeze blew out the flame, the gas was shut off at the burner.

2. There is a Propane switch on my power panel that turns on/off the gas flow via a solenoid in the Propane Locker. I flip this switch off when I go to bed or leave the boat.

3. The propane tanks are in a locker that is vented overboard at the bottom since propane is heavier than air. Last month my pressure regulator sprung a leak which I found because my tank went empty sooner than expected. Opening the locker I could smell the remnant odor. Spraying a little soapy water on couplings found the problem.

4. A Zintex propane sniffer has two sensors located in bilge and near galley floor boards which sound an alarm and cut off gas flow if it smells a leak.

5. Normally I turn off the manual Propane tank valve when leaving the boat for any extended time.

So I have two automatic systems that cut off gas and two manual valves. My propane is stored in a bottom vented locker so that leaking gas doesn't accumulate in the bilge.