Deep Freeze: A Cold, Hard Look at Winter Stoves

Hi Roger-

Yeah, horribly long time… but remember that I was also testing the stove something like 25*C colder than you tend to use stoves. Also of note, I had two of the xperts, and cursory, comparative results between both seemed correlative. "Fair-weather" use around freezing had the xpert boiling a liter in about 5.5 minutes. In another, colder round, the xpert took about 14 minutes to boil vs. 5 for the Lander. Given that I was essentially playing with the (discontinued!) stove, seeing how it compared to the actual test stoves, that was plenty enough for me. That said, anyone have questions about the stoves we covered in the article?

I hoped that the videos would help people get a better idea of the stoves, how they set up, how they burn at different power levels, etc… and I know I've wondered how different items looked from different angles… any feedback on that, folks? Is/was the video helpful, or did I just succeed in giving poor Addie a case of heartburn? Is the video a "feature" you would like to see on future reviews?

I went to REI to look at the Sumo pot. It is still pretty narrow- I think the new Reactor 2.5 pot is going to be a lot better for melting snow. The Reactor puts out way more BTU than the Jetboil Sol in warm temps so it is probably going to do the same in cold.

Remember gas (butane/propane) canisters do better the higher you go because air pressure is less. Just because it works on Everest doesn't mean it will work lower. I'm going to do a test tomorrow morning at 8,000'/freezing temps to see how that compares to sea level.

>"Remember gas (butane/propane) canisters do better the higher you go because air pressure is less."

To the extent that butane and butane-mix canisters can exceed the lower atmospheric pressure at altitude to a lower temperature, yes, they do better at altitude. In that one respect. They will perform when the canister is 5 to 10F colder than at lower elevations.

But less atmospheric air also means less oxygen per cubic foot of air. How ever many cubic feet per meter of air pass through the burner at sea level, the same will at elevation but that volume of air will contain 75% as much oxygen (and nitrogen) at 7,500 feet. 58% as much as 14,500. 50% at 18,000 feet. 45% as much at 20,320. Just like our lungs or an gasoline engine, with less dense air, a burner can't burn as much gas. So (1) max output is down and (2) with less oxygen flow, there's the chance of more CO and unburned fuel vapors, expecially at full throttle and against an ice-cold pot.

I look forward to the results of your 8,000' test. Look for signs of a rich mixture (yellow flames) and if excess fuel gas is combusting outside of the normal blue pre-mix flame compared to sea level.

Hi Brad,

Thanks! I really appreciate the information (and yours too Roger). I can see my path- use the Xtreme until I run out of canisters and then, rather than picking them up for $12 each on eBay (no joke!), I'll just cruise back into white gas country. It was fun taking a ride in the Prius, but the Ford will work too. It was good while it lasted! Thanks for showing a few different options!

And I liked the videos. I probably could have gotten a lot out of just one video per stove, but I enjoyed all of them and found it useful. I also appreciate how thorough you were in your testing. It's hard to follow Roger in this regard but I think your balance of detail and commentary was clear and also enjoyable. I enjoy both of your styles.

Oh- and if anyone out there has a case of Powermax they want to sell, just let me know!

Thanks again!
Doug

I like the videos but maybe you could talk during them. On the first one I thought my sound wasn't working until I put on Pandora to see if it was the computer or me.

"And I'm also curious how the Reactor defied basic thermodynamics to empty an upright canister. What gases did those canisters claim to have?"

The real question is not how it defied thermodynamics – it didn't. The question is how it used thermodynamics to do what it did.

Paul, exactly- thank you.

The particular questions on the Reactor are based on performance figures I obtained through testing for this article, and as noted, at no time did a canister (or a white gas fuel tank!) receive any kind of assistance. I wanted to see how they performed, in severe cold, without coddling. There was no water bath or heating pad or windscreen or any such thing involved. As the video shows, my hand can nearly touch the Reactor pot and burner assembly, so no, it doesn't put out much heat. For the grins of it I made a contraption out of copper wire, made a couple loops each around the pot and canister, a few doubled strands connecting them… no difference in performance. Also of note, I shot some more video, (but it didn't come out for beans) showing the Reactor, assembled, in the freezer. Opened the freezer door, opened the valve on the Reactor, lit the Reactor w/a ~20% full canister. Honestly, I don't care WHY it works, so much as the fact that it DOES work. The only possibility of added warmth during testing would have been rim contact with the ground, but as my "light it in the freezer" round went, I'd guess that ground contact didn't make much difference.

Thanks for the feedback on videos, all! I debated about whether talking would be a distractor or not. Next time will use "condensed" videos, probably not give so much exposure for showing ranges of performance, etc.

Cheers-

I consider the MSR Dragon fly one of the top 5 winter stoves. It can simmer lower than any liquid fuel stove I know of and can be very hot at its maximum. Low simmer is important for baking and warming to save fuel.

The Dragonfly is extremely reliable if the pump is properly maintained yearly. Yes, it is the heaviest MSR stove but it has many redeeming virtues. The one nitpick I have is that I had to file tiny V notches all along the wire potstand top surface to give more friction on the pot bottom. This would be an easy fix for MSR to add.