Cold weather experience w/ a canister stove

Wow; fascinating!

Most of the canisters had very little pressure at *freezing.* So if my canister is at 4-8 PSI at freezing, at what temperature does it hit 0 PSI? -5? -10?

And even if it's -5 out, the canister will quickly cool itself to -10 or -20 through evaporative cooling, and the stove will go out.

I think that Dr. Caffin's advice re: warming the canister is very important below the freezing mark. I think the canister and valve must be kept warm by the flame of the stove to ensure consistent operation.

That said, as long as the canister was kept warm you'd be good to go past -4F/-20C!

Thanks very much for the data and time spent testing!

Hi Brian,

You and others have raised many good questions, doing those simple P/T tests has made me think about more on what is really going on in a canister. I am thinking about doing some more tests. As mentioned in my previous post,I am thinking does the Propane boil off first no matter what is the temperature and what happens in an upside down liquid feed canister.

I am a technician in a university research lab and I have access to a lab that the temperature can be controlled from 4C to 30C but I would like to get access to a lab or cooler that can do -20C to 30C. I am thinking about if I can the tests in a temperature control bath where I can control from -50C up.

I put a 30/70 canister in a freezer at work which measured -24C attached it to my latest liquid feed stove and nothing came out until it warmed up a bit.

Tony

> does the Propane boil off first no matter what is the temperature and what happens in an upside down liquid feed canister.
Try the page on gas mixtures at:
http://www.bushwalking.org.au/FAQ/FAQ_Mixtures.htm
Hopefully they will explain a bit about what is going on.

I have some P/T curves in the FAQ at:
http://www.bushwalking.org.au/FAQ/FAQ_Mixtures.htm#Liqu

Yes, 30% propane / 70% butane does kark at about -20 C.
30% propane / 70% isobutane gets almost to -26 C.

Hi Roger,

Thank you for the link to your excellent Bushwalking.org faq mixtures article. Your Bushwalking.org faq site is a resource that I use all the time.

I compared my data with your p/t graphs. It is nice to know with the 100% full 30 propane/ 70 iso-butane canister that our data matches, but on trying to match the data for the 70% full 30 propane/ 70 iso-butane canister, I am having a bit more trouble. The pressures that I am measuring line up with your figures for pure iso-butane (I will check my pressures again this weekend) if my pressure measurements are correct this would mean that all of the propane has boiled off and no iso-butane has boiled off the canister has not been used in very cold temperatures, but according to your other graph “amount of butane or iso-butane in vapour mixed with propane vs temperature and liquid concentration” this should not have happened.

70% full 30% Propane 70% iso-butane canister pressures.
4C 11 psi/0.75atms
0C 8psi/0.54atms
-20C 0psi(on gauge) I must get a absolute gauge

Tony

Mark-

like I had very much the same problem a few weeks ago with a Coleman Fyrestome ti. I started off with a new smaller canister, jetboil brand. The first time I used it fine. Later that night went to boil snow and couldn't get it started. Warmed the tank then started but dieded out.

I slept with the canister and trypod for it and the next day it started, worked fine and died out again.

When I went home in my apt everything worked fine. I was told by a friend I should have tired using a larger canister because it would create more pressure.

I've read any good reviews of the coleman stove so I'm not sure what I was doing wrong both times I used it camping I kept the canister in my coat for at least 15min before use. I was in a wooded shelter on the trail so wind was even an issue. Temps were around 0 or a little lower. I even went as far as keeping the canister next to the stove to keep it warm?

On the same trip my other friend was using a small jetboil. Both days his lighted and burned. It was not as hot as hot as it should have been but he wasn't pre heating the caninter or using any insulation.

I must say after this happend to me twice I'm a little put off by the Fyrestome.

Any tips or ideas would be helpful.

Joe F.

Hi Tony

> The pressures that I am measuring line up with your figures for pure iso-butane (I will check my pressures again this weekend) if my pressure measurements are correct this would mean that all of the propane has boiled off and no iso-butane has boiled off
Not so. What is very possible is that 95% of the propane has boiled off and 50% of the isobutane has boiled off. This would leave a tank about 1/3 full, but containing mainly isobutane. The amount of fuel left in the tank does not affect the pressure.

Hi Joe

>I started off with a new smaller canister, jetboil brand. The first time I used it fine. Later that night went to boil snow and couldn't get it started. Warmed the tank then started but dieded out.
> I slept with the canister and trypod for it and the next day it started, worked fine and died out again.
> I even went as far as keeping the canister next to the stove to keep it warm?

Now this is different, and strange. You mention the tripod, so I assume you were using the canister upside down as it should be. It seems to me that your problem has to be dirt or gunge somewhere in the system, or a poor connection. I have had problems with the valve on an MSR WindPro when I was using a canister upside down: the valve kept getting blocked. But this should not happen with the Fyrestorm imho.

Check the jet to make sure it is clean. Check the connections too, to make sure they were fully mating. There have been a few cases where the Powermax canister has had trouble mating to the Xtreme stove.
Check that you were screwing the canister onto the tripod fully: if you don't the valve inside the canister won't open properly. Don't be brutal!, but check the connection is fairly tight. There is an O-ring to be compressed inside the connector.

If you can get the stove into the cold again and it seems to be giving problems like this, you could try opening up the valve a full turn briefly (or shutting it right down briefly) to see if this improves things – by dislodging any gunge in the valve. If it does, you may have gunge in the valve.

> I was told by a friend I should have tired using a larger canister because it would create more pressure.
Nope. Doesn't work that way with a liquid feed. Can have some influence with an upright stove in the snow afetr a lot of use.

Lots of good info being posted here. I've had good luck with the Jetboil stove in below freezing temps. Last night and this morning I used mine at 25F – 15F with 10mph wind (hands for windbreak). I heated 8 cups (two at a time) of almost freezing water (taken from frozen over stream) to a rolling boil for three minutes, and my small canister seemed to still be going strong. I wouldn't take it if I was expecting 0 or below, but it works pretty well below freezing.

Rodger thanks for the advice and tips.

I will take it out next week and give it another try. The double valve system even though it's for our safety I found makes flame adjustment harder to use plus wastes fuel.

Joe F

Over the years I've figured out what my problem was with the canister stove I have. Even on a full canister and being in an igloo where it is warm enough for the fuel to vaporize, I found the stove sputtering after 20 minutes or so of burn time.
Well, it turns out that the heat warms up the stove and canister and the metal expands. I found that I could again tighten the stove onto the canister about another 1/16 of a turn and the stove would perk right up.
I can't see this being relevent in a liquid feed stove with the canister that far away from the heat source but…

Hi Ed

> Well, it turns out that the heat warms up the stove and canister and the metal expands. I found that I could again tighten the stove onto the canister about another 1/16 of a turn and the stove would perk right up.
Yeah, I can see that happening with an upright. Great bit of info, thanks.

> I can't see this being relevent in a liquid feed stove with the canister that far away from the heat source but…
Hum – true. Joe's problem may be different – dunno.

>>I can't see this being relevent in a liquid feed stove with
>> the canister that far away from the heat source but…

>Hum – true. Joe's problem may be different – dunno.

Hi Roger,
Maybe Tony has an IR thermometer and could check the line temperatures.
We put up a page on my recent trip to Yellowstone where I used cannisters: http://www.grandshelters.com/yellowstone-2007

Dunno about -40 & the exact percentages, analyses, etc., but I know my buddy's Xtreme stove didn't want to do much of nothing at all in 30 below. It had some gasket and freezing problems, perhaps due to the relatively high humidity of quebec winter?
When crunch time comes, I don't want to be messing around with the theoretical workings of canister stoves, and prefer to get a flame going using white gas.

> I know my buddy's Xtreme stove didn't want to do much of nothing at all in 30 below
Is that Centigrade or Fahrenheit? :-) (Yes, I know there is precious little difference!)

But you are right: the Powermax canister has very little pressure, if any, if it is at -30 C.

> When crunch time comes, I don't want to be messing around with the theoretical workings of canister stoves, and prefer to get a flame going using white gas.
Ah, but white gas is going to be even less useful at that temperature unless you warm it up. OK, the preheat tube will do that once you have got the stove going, but you first have to get it lit and running. How do you prime it at -30 C? Alcohol at -30 C won't light either, nor will a butane lighter.

Yes, I can do it, but YOUR methods will be of interest. :-)

Cheers

Really? White gas won't light at -30?

I have run coleman double-burner stoves at -40, but it was like 20 years ago and I can't remember if they were hard to light.

Could you tell us more?

Probably showing my age here but I've never tried to use a butane cannister stove since a winter trip on Mt. Shasta in California with a Bluet stove – basically it wouldn't work. I switched to a Svea or other newer liquid fuel stove and burned hexane or pentane in winter which worked great and octane (white gas) in the summer. I had access to chemical solvents as part of my job so I could do this. I did make the mistake once of using hexane in the summer – not a good idea! Luckily the Svea had an overpressure release valve. I always put the stove on a 4" x 4" piece of 1/4 in plywood for insulation. I used hexane in the Svea down to -30 with good results.

Hi Brian

> Really? White gas won't light at -30?
> I have run coleman double-burner stoves at -40, but it was like 20 years ago and I can't remember if they were hard to light.

Well, let's start by remembering that liquids don't burn: only gas burns. So whatever the fuel you are using, it has to be vaporised: it has to reach boiling point. A liquid below its boiling point only gives off a little vapour, like warm water evaporating compared to water boiling.

A lot of the discussion in the Forum has been about propane (C3H8), which boils at -42 C, and butane (C4H10), which boils at -0.5 C . White gas uses much heavier hydrocarbon molecules – in the C5 – C10 range I think, and has a correspondingly higher boiling point. There is not going to be much vapour coming off it at -40 C! So finding enough vapour to light could be difficult. Equally, alcohol at -40 C has not a lot of vapour either.

However, if you can warm up a little bit of it with a match say, then you have a chance to get some feedback going and the stove may start to prime. Little different from ordinary priming really. Incidentally, priming kero is even more difficult for the same reasons.

Why a match? Because a match head contains its own oxidiser and can be made to light under quite cold conditions. A butane lighter probably would not, unless it had been living inside your clothing (which is not a bad idea, btw!).

The comments about pentane, hexane and octane are entirely appropriate, and I agree and have done the same thing myself. However, they are not easy fuels to obtain in ordinary shops.

What about auto gas? Well, winter gas at least usually contains some butane. This should be obvious if you think about how easy it is for auto gas to 'flash'. Dangerous stuff. That is why we have Shellite and Coleman Fuel: they are similar to auto gas but without the noxious additives and without the butane and (iso)pentane components which can flash easily. The manufacturers leave out the really volatile components to make them safer.

"Is that Centigrade or Fahrenheit? :-) (Yes, I know there is precious little difference!)"
Farenheit; if I'm not mistaken that's like -32C or so? I can't think in metric unless I REALLY push myself ;-)

"How do you prime it at -30 C? Alcohol at -30 C won't light either, nor will a butane lighter.
Yes, I can do it, but YOUR methods will be of interest. :-)"
Neither; I use white gas to prime, ignited by a NATO match or a Zippo lighter.
You?

> "How do you prime it at -30 C? Alcohol at -30 C won't light either, nor will a butane lighter.
> Neither; I use white gas to prime, ignited by a NATO match or a Zippo lighter.
> You?
I carry my Bic lighter inside my clothing so the butane stays well above its boiling point. Then I hold it inside my hand so it doesn't cool down while burning. Plenty of heat in the flame.