Debunking? the Soto OD-1R Upright Gas Stove.

I have mixed feelings about the Soto OD-1R. I suspect that it's just another upright canister gas stove and that it won't operate in temperatures any lower than any other upright canister gas stove. It may or may not be a good stove, but the marketing hype has been around how its regulator somehow allows the OD-1R to operate in colder weather than comparable stoves.

I am going to list my reasons below why I don't think the OD-1R will operate in temperatures that are any colder than any other stove. I'm interested in hearing people's feedback and comments.

Here's the deal: the maximum amount of pressure in a canister is the maximum amount of pressure in a canister. What I mean by that is that no burner can pull more than the maximum amount of pressure available. The pressure available is governed by the boiling (vaporization) points of the constituent fuels, the air pressure, and the temperature of the canister. At sea level:
Boiling (vaporization) point:
n-butane -0.5C/31F
isobutane -12C/11F
propane -42C/-44F

These temperatures are hard facts and no stove can alter them. Unless the Soto OD-1R is transferring heat down the burner column like a Svea 123, then the OD-1R will have no more pressure available than any other upright canister gas stove. If the OD-1R is transferring heat down the burner column, run away as fast as you can -- or only use it in cold weather. I highly doubt there's any Svea 123-like heat transfer going on.

OK, so what if anything does a regulator buy you? Well, if you set the flame on less than maximum and let the stove burn for a while, on an unregulated burner, you're going to have to periodically fiddle with the flame in order to keep the flame consistent as the canister empties. In a regulated burner, the regulator can compensate for a loss of canister pressure by opening the valve wider -- up to the maximum amount of pressure available. And there's the rub. The maximum amount of pressure is not governed by the regulator; it is governed by the fuel(s) and the conditions.

Example: Say it's a really cold day. You're having trouble getting pressure out of your gas canister. Now let's look at the difference between a regulated and unregulated upright canister stove:
1. You open your valve fully on your unregulated upright canister gas stove, barely a "phft" comes out. That's it. That's all the gas you have available unless you change one of the physical factors of the equation (fuel composition, air pressure, canister temperature).

2. You open your valve fully on your regulated upright canister gas stove, barely a "phft" comes out. That's it. That's all the gas you have available unless you change one of the physical factors of the equation (fuel composition, air pressure, canister temperature).

If you read the two statements above, you'll note that the only difference between #1 and #2 is the presence of the letters "un." In other words, there is no difference. The maximum amount of pressure available is the maximum amount of pressure available. This maximum pressure available is true for the cheapest all-steel burner head on up to the most expensive upright you can name (think MSR Reactor).

The regulator, if there's sufficient pressure in the tank, should give you a more consistent flame so long as keeping the flame consistent does not require more pressure than the maximum available.

The regulator will not allow you to operate an OD-1R in temperatures that are lower than the temperatures other comparable stoves can operate in.

Either that or my understanding of chemistry and physics is completely wrong. Comments solicited and welcomed.

HJ

 

Just heard of this stove. Interesting stuff. I would agree with you Jim. Seems to be marketing at its best but I would be interested at taking a closer look at the stove.

Check out the companies website
Link

Jeff

 

Or marketing at its worst...

HJ

 

Soto mentions on their site that the stove can boil X amount of water in Y minutes at -5C.

Note the following:
Boiling point
isobutane -12C 11F
propane -42C -44F

So, if they have a standard backpacking canister, their canister contains some mix of isobutane and propane, both of which vaporize and burn quite well at temperatures lower than -5C. In other words, the micro regulator isn't doing anything unusual. The stove is burning vaporized gas at a temperature that is within the normal limits for that type of fuel. The micro regulator isn't doing anything that any other stove couldn't do.

I do see all the awards and such, and I'm sure it's a well built stove, but in cold weather will it do anything more than any other stove? I don't believe so.

And, yes, I've seen their ice bath video. What temperature is an ice bath? Well, since not all of the water is frozen, the temperature cannot be below 0C. Is operating a stove at 0C with an isobutane/propane canister a big deal? Not really. Recall that isobutane, the major component of the two fuel blend, vaporizes just fine at -12C. Add in propane and you've got a mixture that will vaporize lower than -12C.

So what are we seeing in the video? Clearly the stove on the left has reduced output. Hardly surprising. Any canister that is cooled will have reduced pressure. Since the stove on the left is presumably a standard needle valve, the flame will be reduced -- unless someone changes the setting on the valve. The stove on the right has a regulator. The regulator can allow more pressure to escape from the tank without intervention, provided that additional pressure is available in the tank. At 0C, an isobutane/propane mix will have a good deal of pressure.

Now, if having a constant flame automatically is a big deal to someone, then the Micro Regulator will be a good stove for them. For the rest of us, we can just open the needle valve a bit more and adjust the flame manually.

What I'd like to see is for them to repeat the same test with 100% butane (not isobutane) which has a boiling point of -0.5C, very close to the temperatures of the canisters in the experiment. That would be a more valid test. If the Micro Regulator stove can make a difference under those conditions, then they'd really have something.

Hmm. That's actually a test I could do myself fairly easily. An ice bath is fairly known temperature.

HJ

 

I had read a year ago or so about the stove being able to adjust iself. Also there were mixed reviews. Some worked fine, others not so.

 

I have reasonable confidence that the regulator will work -- so long as there is additional pressure available in the tank. If you need a stove with a constant flame and don't want to fiddle with the valve manually, then this would be a good stove.

However, the way they are marketing the stove makes it look like they're claiming improved performance over other stoves in cold weather, but
they're not giving it a real test. Testing a stove at 0C with a fuel mixture that will vaporize below -12C is hardly a test.

What I'd like to see is a test where the canister temperature is close to the vaporization temperature of the fuel being used. If there's a difference between their stove and others under those conditions, then they're on to something. Inasmuch as they'd have to violate the laws of physics in order to do it, I'm a little skeptical.

HJ

 

I figured they had some new fangled electronics going on. Didn't spend much time analyzing what they might have come across.

 

Well, it does have a piezoelectric starter. I suppose that's something.

HJ

 

They run it on there own gas and I cant read the blend.
When it comes to hiking with gas surly the principle of KISS should come into play. People take gas because they want no problems or difficulties. This is best achieved by a stove with the smallest number of parts. Keep it simple means its more likely to just work.

 

My first stove (and many other people's!) was the Campinggaz one with piercable canister. Simple as simple can be! Open it, light it, and let it do its job 'till the canister runs dry. This Soto thingy is typical for our times; if you want to sell, add unneeded gizmo's! Only makes a probably nice working stove more "breakdownable" (think I invented a new word here )

Take care,

Wim

 

I agree with your idea that using standard gas blend, it can only make cooking a little easier by skipping the fiddly bit, not alter the laws of physics.

A thought could be, that since theres a regulator, they've got their own mix, using something similar to the Sievert Powerjet all propane cartridges, which of course gives better cold weather performance.

EDIT: found this specification: "Component ● / liquefied propane, liquefied isobutane, liquefied butane"

I guess that means the same sloshing around of ungassified butane when the is propane burned off, as with all the other popular mixes..

 

I did not look at the water/ice bath video, but it sounds like a nice misleading demonstration intended to fool those who do not understand the physics behind evaporation. At low temperatures the water/ice bath could enhance stove performance because even 0° water is a source of heat and will prevent the gas canister from cooling itself to below that temp.

 

Exactly! What do backpackers do with a gas stove when it gets cold? They put the canister in water. Any liquid water, even 0C water, will keep your canister stove running better in cold weather.

In other words, this "demonstration" was nothing.

Pysen, thanks for finding the gas blend.

Wim, I agree. If you can't actually make a better stove, then you have to make people think you have made a better stove. The regulator buys you very little, but you have given up simple, proven technology for unproven, more complex technology.

HJ

 

Altering the laws of physics is a really demanding job

The Soto is a marketing gag, nothing else.
I recommend the review of this stove on BPL.

Just for the records, there is an upright stove heating up the cartridge a bit during use: Coleman F1.
The housing of the F1 is aluminium throughout heating up quickly to a point where you can no longer touch it at the bottom.....
It sometimes helps to squeeze out the very rest of gas from a cartridge.


juergen

 

Interesting, on all accounts. Thank you.

HJ

 

HJ,

the F1 gets really hot.
Mounted on a Brunton stove stand you can even work with liquid fuel supply (cartridge upside down) after some time of preheating.
Then you even have perfect regulation with the valve directly below the jet.

juergen

 

Really? So it's hot enough to vaporize it's own fuel? That's fascinating. Have you tried it in very cold weather?

How do you like the Brunton stove stand? Does the connection rotate so that you can invert easily?

HJ

 

Yes, it's hot enough.
The little space below the jet works as a vaporizing chamber, later on the top of the stove stand gets hot as well. That's sufficient, you only need a few degrees above 0 to vaporize butane.
I only tried it here in winter and it worked, but the cartridge was half full.

The hose/connection rotates easily, yes.

Try to get one as long as they are available.
As far as I know Primus has taken over Brunton, that might be the end of the stove stand since it's made by Kovea...

juergen

 

I've had those thoughts too (about getting a stove stand while they're still available). Maybe an F1 now too.

HJ

 

HJ.

There are different versions of the F1.
The standard version with steel legs is sufficient and relatively cheap.

juergen