THE BUTTERFLY #2412 PRESSURE STOVE

Kerosene pressure stoves have been used for over a century precisely because they are reliable and versatile.  They will work at high altitude and when burning poor quality fuel. And they burn HOT, boiling 6 cups of water in less than 7 minutes, so cooking or purifying water is fast.

(Above, photo of my pressure stoves for testing: Primus No. 96 version 5, late 1920's;  Aida #100, 1960's; Butterfly #2412, current; Karan #212, 1997.)

Both the Primus No. 96 and Aida No. 100 shown in the photograph above were designed so the burner could be removed and the fuel tank sealed, but those stoves have not been available for years. The Butterfly #2412 is the only pressure stove available today designed for really portable use!  Combined with the multi-fuel capabilities of this stove, this makes it one of the most versatile and valuable stoves anyone could ask for to use in an emergency situation. 

The Butterfly #2412 stove can be assembled quickly for use

The Butterfly 828 pressure lantern makes a fine companion piece to the Butterfly pressure stove.  For more information on the 828 lantern, click here.

St.PaulMercantile.com is the source for Butterfly stoves and pressure lanterns and has them in stock.

INSTRUCTIONS FOR USE:

To light the #2412, first fill the tank with clean fuel through a filter funnel* until it is about 3/4ths full. Pour some alcohol* into the alcohol cup, make sure the air bleed valve on the filler cap is OPEN, then light the alcohol.  Just before the alcohol burns up (easily visible), tighten the air bleed valve on the filler cap, pump the manual pump on the side of the fuel tank, and the stove should easily begin putting out heat. If the ambient temperature is very low (below 40 F), it may take two fillings and burnings of the alcohol cup to preheat the burner assembly properly. If lighting outdoors, block any wind from blowing the heat from the burning alcohol away from the burner. In an emergency, virtually any fuel can be used in the alcohol cup for preheating, but expect some sooting on the burner unit.

You can begin cooking immediately. If you need more heat, just pump a few additional times to build more pressure in the tank (Remove any boiling liquids on the stove first, though!). You can hear the heat output differential, so there isn’t a problem regulating the BTU output. To lower the temperature, simply unscrew the bleed valve a quarter turn and listen as the pressure lowers and therefore the BTU output decreases, and tighten the bleed valve when you have lowered the temperature sufficiently.

Let me give you an illustration. Bette wanted to cook some rice on the little #2412. The first thing you need to do is boil water, so I had the stove pumped up to produce a high heat. The water started boiling in only a few minutes, and then the rice and butter was put into the boiling water, which of course immediately cooled the water below the boiling point. In a couple of minutes it was boiling again, so I opened the bleed valve to lower the temperature output to a gentle simmer, then tightened the bleed valve again. The rice cooked perfectly without scorching on the bottom, and I had some nicely cooked rice for lunch. Bette wanted to heat some beans, so they went into small pan, I pumped up the stove about 5 strokes, and the beans heated to boiling quickly, as which time I lowered the temperature (open the bleed valve for a moment) so they could simmer. When the beans were cooked, Bette turned off the stove by simply opening the bleed valve a half turn and leaving it open.

With 0.6 L of fuel in the tank, you have about 4 hours of cooking time available with the #2412: obviously, these stoves are extremely fuel efficient! One liter equals 1.0567 quarts, so a gallon of kerosene will yield from 24 to 32 hours of operation, depending upon the pressure at which the stove is operated, which should be enough for several weeks of cooking or heating water for washing.

All kerosene pressure stoves follow the time honored design principles of the old style gasoline torches: The fuel is preheated in a tube until it volatizes, the vapor is blown through a very small venturi jet in a nipple and burns completely as a vaporized fuel/air mixture. Safety in terms of pressure is not a factor, as the jet is always open...it is virtually impossible to build up too much pressure in the tank. But that open jet design means the tank is not sealed, so if the stove is to be transported after use and fuel remains in the tank, be sure to transport the stove in the upright position and with the bleed valve open. If you are hiking or carrying the #2412 stove in such a way that it cannot be carried upright, then use the supplied wrench to remove the burner assembly and replace it with the brass cap, and tighten the bleed valve on the filler cap. It only takes a couple of minutes to perform this procedure, so it isn’t time consuming or difficult.

Notice the "*" above? Those were put there to alert you to avoid potential problems. Kerosene pressure stoves vaporize the fuel through a tiny jet hole, remember? The stove comes with a jet cleaner in case the jet becomes clogged. That, of course, is why you should use a filter funnel when filling the fuel tank...why borrow trouble with dirty fuel? Preheating with alcohol is best done with the highest temperature burning alcohol, which means 91 to 95% alcohol, not 70% rubbing alcohol. Alcohol burns very hot, without much of a visible flame and produces almost no soot. In an emergency you could preheat using kerosene in the alcohol preheat cup, but expect it to leave a soot deposit on the burner and require several cups of fuel to achieve adequate preheating.

Can a kerosene pressure stove be used indoors in an emergency? Certainly. They burn without noticeable fumes, and because they burn kerosene it does not produce excessive carbon monoxide as do gasoline stoves. [Always open a window a bit when using any device with an open flame...they burn oxygen, too.] These stoves are too small to support an oven, but with a support stand to hold the oven with the stove beneath, they easily put out enough heat to properly heat the oven...it just isn’t ideal for that purpose. The #2412 is a pressure stove...they do have a sound. It isn’t as loud as a Coleman stove or lantern, but you can hear the mild roar of the burner unit in operation, just as you can with a Primus kerosene stove. Unlike the tiny Primus, however, the Butterfly #2412 is large enough to use for daily cooking, if required.