Is the SVEA 123 still a viable stove option for winter?

"Is the stove really that sensitive or did these folks screw up?"

Follow the instructions and maintain it and it will never fireball or overheat. Buy some gaskets for the cap and replace periodically.

The only Svea that I saw burst into a fireball was the fault of its owner. He had no idea at all of how to prime it. A little experimentation at home helps.

–B.G.–

Well, this involves a piece of physics when you use the stove.

You do NOT actually apply heat to the tank, except as needed to prime the expansion chamber. The expansion chamber is the brass valve/burner assembly on top of the stove, there really is no expansion chamber, except in function. This heats the WG to evaporation (boiling.) The pressure sends the fuel out of the jet to be mixed with air & burned, AND, sends pressure back into the tank. Temperature and pressure are directly related in a closed system, so, the pressure is condensed in the liquid fuel, warming it. This supplies more fuel to the "expansion chamber." It sounds kludgey, but it works quite well. In open air, no pot, no windscreen, the tank warms as much from this as well as conduction through the metal parts (a given.)

This is the same mechanism as boiling water. Note that steam is created near the bottom, then, as bubbles rise through the water, they disapear and are re-absorbed into the water, releasing heat. Another, perhaps better example: The capuchino maker on many small expresso machines supplies steam to the milk. This will warm the milk simply by the milk absorbing some steam.

Anyway, it only requires a small bit of combustion to do this since the heat causes some expansion forcing raw fuel into the "expansion chamber."

Overheating is typically caused by large pots over a SVEA while using a wind screen. The simplest solution is to pour a bit of water on the stove. I know, this is counter to pouring water on oil flames, but we are not dealing with liquid fuel, here. Rather fuel vapour that is being vented. The water will simply reduce the heat in the tank, reducing the amount of vapour pressure, from overheating, being produced to vent out the safety valve. Hence, will pretty much reduce the stove output to normal conditions. The safety valve may stick, though. but it will eventually extinguish the stove, or, allow you to turn it off. Even the pot of water on the stove will be fine, boiling water is much cooler than the stove, IFF (if and only if) it overheats.

Did you ever boil-over a pot? It will put the stove out. I have done this several times, since I use a wind screen all the time. The stove will NOT explode. I recommend only low heat when using a wind screen. This is OK with me, since, lower heats are very efficient with fuel, anyway.

Generally, on low, fireballs cannot not happen. Even on 100F days in the sun, the stove will not overheat on low before you are done heating water. I have never gotten the stove to overheat with only a pot on top. Using a windscreen can cause ANY canister type stove to overheat. Canisters of compressed gas are much more risky, since, they have NO safety valve, like a SVEA has. Compressed gas canisters under the same conditions can explode, the SVEA will simply vent excess pressure, preventing the explosion.

You have to really misuse the SVEA to vent the safety. It is not recommended to use a wind screen, I do anyway. Knowing the parameters for any stove is the key to safe operation.

I've heard of one guy who primed his 123 by just pouring some fuel over the whole stove, of course after numerous times doing this, his stove was black. Like cold canister fuel, you can heat the tank/fount on the 123 to create some pressure, then light, or use the pressure to push some fuel out to use as primer.
Duane

There is a small indentation on the top of the tank where the stem to the burner connects (priming bowl). You need to put some fuel there and then light it. If your timing is perfect, when you open the fuel key just as the priming flame extinguishes, it will ignite the burner.

Some people carry a small eye dropper and pull fuel from the tank and place it in the priming bowl.

Some people carry a small bottle of alcohol and fill the priming bowl with this.

Some people place fuel paste in the bowl.

Some people light a few pieces of scrap paper and hold the stove over this until the tank builds pressure.

The instructions say you can cup the tank in your hands to warm the tank, then open the fuel valve and WG will dribble down into the priming bowl — this has never worked for me.

And then there are those who douse the entire stove with WG, throw a match on it and run away :) …. probably the same people who light campfires by dousing the wood with fuel.

My wife told me my "weirdy stove" arrived (A little sooner than I thought). Way down in the corner of this big, lonely cardboard box was this little stove. Pretty un-exciting packaging and instructions – written in 4 languages all of which say the same: fill, prime, light, enjoy and don't burn up. I like that.

So I filled it, primed it by warming the tank with my hands until it gurgled up some fuel which I then lit and let it burn down. Then I lit it and away it went.

Not sure why folks say it is noisy – it isn't compared to other white gas stoves. Yes it is noisy compared to my alcohol stoves, but then so is most everything.

Boiled water like it is supposed to, and it simmers really well. I can get it down to below the level of boiling water and it stays there (it was pretty breezy). I'm going to use it with the Optimus Weekender HE .95L pot, (when it arrives), to make the most of the limited BTU output of the little guy.

The key is stupid, so I moved it almost immediately.

Cute little bugger – I can see how folks fall in love with them. It is so simple that it has just got to be reliable, and that is of utmost importance to me. I wanted white gas for the cold-weather BTUs, but the MSR stoves kind of turn me off because of the bits & pieces. There just isn't much to go wrong with the little SVEA 123R.

Wish I had picked one of these up earlier in life.

You just outlined why I use the stove: Reliable, durable, simple, and efficient.

The key is usefull for field maintenence besides controlling the valve. It is certainly possible to use it without, though…never had a problem in the field in more than 40 years of use.

It is a bit heavy for the BTU output, but, that also makes it very efficient with fuel. My thought was to revamp the old design using totanium for all except the valve/jet assembly. The weight would go down a LOT. But the origonal is a very compact heating system.

Add a wind screen, but be carefull with the heat radiated down to the can. It can get quite hot if you don't watch it. On low this is perhaps the most effecient stove available.

> there are those who douse the entire stove with WG, throw a match on it and run away

And there are those who open the valve slightly and stick the stove in the campfire until it is roaring.
I kid you not. We stayed a long way away though.

Just one more question and then we can let this thread die. Do you need an insulating pad under the stove on the snow, or does it work better without one? I'm wondering if the little bugger will run if the tank is heatsinked? I.e. is it ok running on wet ground or does it need to be sitting on something dry? Thanks for your help folks and I hope this thread is helpful to someone else considering one of these stoves.

If the snow is cold, then it has the effect of slowing down the pressurization of the Svea fuel tank. A good platform can be fashioned from a piece of plywood or Masonite. It doesn't have to be a fantastic insulator, but a stiff platform like that is very helpful.

For wet ground, it will work without any platform. OTOH, a piece of aluminum foil underneath it might help.

–B.G.–

This a good video of using a SVEA in snow

http://www.youtube.com/watch?v=HUihCydKhBQ

I have a SVEA 123 and think it is great for solo use in any weather. My work colleague who doesn't count any mountain under 6K metres, laughed when I showed it to him. He thought it "wimpy" and inadequate for snow melting for a climbing team of 3 or 4. He uses an MSR NGK.

The tank of the stove is frozen in a block of ice. The guy primes it and it lights right up. Interesting use of a wick.

> Do you need an insulating pad under the stove on the snow, or does it work better without one?

I always use a small bit of light 3-ply under my stove in the snow. It prevents the snow from melting and allowing the stove to fall over!

Cheers

This is an old thread, but I was looking up what people were now using for winter camping and came across it.

First, I'll say I'm the guy in the videos that several people linked to reviewing the Svea 123R:

http://www.youtube.com/watch?v=HUihCydKhBQ

Just to clarify, I do use the Svea 123R for winter camping from time to time. It is plenty fine for melting snow for 1-2 people. Any more than that I'd want either a second stove, or something with more output. I also use canister stoves for winter camping as they tend to be easier/safer to use in confined areas vs. any whitegas stove.

All these stoves have pluses and minuses. For the Svea:

Pluses:

1) Extremely simple. It has one moving part: the valve.

2) The only part I bring for a repair kit is a spare cap in case the gasket on the operating cap is damaged or the safety valve were to activate. I also bring a wick, but I've never had to use it either.

3) The only reason the safety valve will activate is user error getting the stove much too hot. Don't surround it with a wind shield and it will be fine. If you can't touch the fuel tank without getting immediately burned, you are running the stove incorrectly and you should shut it off and allow it to cool.

4) Heat from the stove vaporizes the fuel. The fuel tank gets warm/hot during use, but should never be so hot that you can't hold your finger on it for a bit. The design is quite ingenious as it eliminates external pumps and maintenance.

5) It was made in Sweden where it's cold. So yes, it does work fine in the winter!

6) For an overnight or two, you can just use the built in fuel tank and not bring an external tank with you so you save weight/space
in your pack.

7) Very compact design and extremely rugged.

8) No heavier than an MSR stove when you include all the MSR extras you need with the stove like windscreen, spare parts kit, etc.

Minuses:

1) In very cold temps it can be harder to start. You need to give it a good hot prime to get it going. Maybe even two primes sometimes.

2) I carry a little 4×4" piece of foam I place the stove on if there is snow or a very cold ground. This foam weighs almost nothing and
can also double as a pot holder. The foam allows the stove to reach operating temperature and it will reliably burn even in cold weather no problem.

3) Heat output is not as much as an external pump stove like XGK. So if you are thinking very cold weather expedition or high mountaineering, the Svea may not be the best choice. Although it would still probably work, just slower.

4) I wouldn't use it inside a tent vestibule or near anything flammable just as I wouldn't any white gas stove. I also angle the release valve away from people just to be extra safe in case it were to activate.

Overall, I am drawn to simplicity of the Svea 123R when needed. Mostly I use an alcohol stove for three seasons and I'll even use alcohol for four seasons if I know I won't need to melt snow. Otherwise, I bring the Svea or canister stove.

But the Svea is not down and out and compares very favorably to modern pump stoves. In terms of weight, I think it is a wash once all the extra MSR bits are factored in. In fact, I trust the Svea more and unlike MSR stoves, I've never had the Svea spray fuel all over the place, throw a big fireball, or break due to a pump failure.

Hope that helps…

I agree with what Craig says about the SVEA 123 for winter use. It's viable for a 1-2 people. And/or as a backup or second stove in a larger group. I'll add that there is (was?) a little pump that aided priming it, especially in cold weather. Not necessary, but it made it all easier.

I also agree with Roger – a small piece of 1/8" / 3mm plywood makes a more stable and compact platform than a piece of foam. More heat resistant, too. PM if you need a piece sent to you, I keep a few sheets around at all times. It could potentially double as a handy cutting board (leave it home when in bear country in the summer).

A while back, we got into a discussion of a modern 123 from titanium. I looked at density, thermal conductivity, etc, and it appeared to be problematic – conducting enough heat downward while gaining the weight advantage of titanium. More likely to make aluminum work.

I finagled one of those foldout three legged gas canister stands to fit on my Svea. A little dremel would probably make it fit perfectly. So I carry that in my kit and it gives a 1/2" gap from the ground, stabilizes the stove, and lets it work on colder ground. Although the foam still works better directly on snow.

"a small piece of 1/8" / 3mm plywood"

Another alternative is Masonite in this thickness. If you want to make the Masonite virtually fireproof, then cover it with aluminum foil. Then, even if you manage to dribble some white gas, it survives.

–B.G.–

Also, I did have a pump for my Svea 123R, but sold it as I never used it. I just carry a few coffee stirrers I use as fuel droppers. I dip them in the fuel tank and drop the fuel into the depression on the top of the tank. I then replace the cap and light the fuel. This always works for me to prime the stove even in some pretty cold weather.

I don't have once but find the 123 and Coleman all in one units (422 533 etc) to be strangely alluring due to their aesthetic qualities and drop dead functionality. I use mostly canister and alcohol stoves depending on the trip and have a white gas stove for cold weather (primus express lander vf) but would like to have a 123 and Coleman. I really appreciate the engineering and design even if inverted canisters arguably make them sort of obsolete.

I'm just the same. I've got the Svea 123r, Coleman 550B and 533. Something about the look of these stoves drew me to them. Lovely combination of old school cool in the looks, simplicity and reliability. I'll acknowledge that a cold hard analysis of my needs would have me using alcohol or canisters, and I mostly this is what I do. But as you said there is something fascinating about these old designs.

Yes, the SVEA 123r is a nice little stove and is especially usefull at higher altitudes. It works fine for solo or two person excursions. Dependible, rugged, and efficient. As efficient as any WG or canister stove on the market. (Typically, I get between 10-13g/L.) So far no one has mentioned the packing volume. It is very small to carry, about 2" less than a Nalgene bottle in height and around the same diameter, soo, it fits into a pack pocket easily.

I carry a small soda bottle for fuel. These come in several sizes making it easy to taylor them to the length of trip I will take. For short overnight trips, I often don't bring one, using a small straw(1-2g) to get priming fuel right from the tank.

A spare cap is made up from a piece of 12ga wire shieth or an empty pen ink casing. A small hole is drilled and the tube is warmed, then pushed into the cap. I used to glue it in but quit doing that because nothing really sticks to the plastic that well. The friction fit works as well. I leave about 1-1/4" sticking out to aid in priming and filling. I aim the tube down into the stove for priming. This also lets me recover extra fuel when I overfill it. It saves the mess and fuss of spilled fuel. A typical 12oz bottle of fuel, including the bottle and cap, weighs about 10oz.

The 123 works well at 10,000'. With the wind screen, it is possible to boil about 1L of water without popping the saftey. I use this all summer for my regular one and two week trips. (I'm retired so I get to go whenever my wife will drop me off somewhere, >60 nights so far…) I typically use about 10oz for two weeks at about 1.5-2L per day. I usually cook some sort of stew/soup/rice/pasta for supper. 29-30oz total starting weight for two weeks out. This is competitive with most at my usage.

I discovered that a short length of wood stove door gasket, (1/4" diameter from ACE hardware), really improves cold-weather priming. Tie it or wire it one at the base of the stem at the indentation. Use a straw to draw out some fuel and soak the wick.

And the stove definitely burns hotter if you keep the tank bottom off the snow. And if you are worried about popping the valve while using a big pot in the hot summer, let the tank sit in a pan of water, or in a puddle.

Love the simplicity. Love the shiny brass. But I've only used mine for 2 seasons, so I'll need to check back in 25 years.

Quick SVEA 123 tip:

A Snow Peak Trek 700 mug fits directly over a SVEA 123 if you eliminate the supplied cup. This provides a compact, practical and self-contained white gas option for cold winter trips where canister stoves aren't ideal.

I got my Svea 123 in May of 1975… it's still going strong!

I just douse the spirit cup with fuel and light her up.

I've used it at -20*F and 100+*F and it's always worked, and worked well.

Not as light or convenient as my Jetboil Ti, or as stables as my MSR Whisperlite Int'l, but it's a wonderful little contraption that has the other two beat in terms of sheer simplicity and long-term durability.

I used to carry an eye dropper with me when I camped with the Svea. I'd open the fuel tank, fill half the eyedropper, close the tank, put the cage back on the stove, fill the spirit cup with the fuel from the eyedropper, light the fuel and I'd have almost an instant prime. The eye dropper doesn't weight much compared to the pump, which I had once and never used–I didn't know how the cage could fit with the pump installed–maybe you had to cut away part of the cage to use the pump.

Nowadays, I don't camp much where I have to melt snow. Alcohol and canister stoves cover me.