Lighting pressure stoves (e.g. Shellite, kerosene and similar fuels burned under pressure)
There are many types of pressure stoves, and all have different procedures for lighting and use. Always read and follow the manufacturer’s instructions. Before taking a new stove on a trip, always try it at home first to familiarise yourself with its operation. Read the manufacturer’s instructions. Preferably try it out in the open, or on a level concrete floor, e.g. in the middle of an empty garage. Never bend over a stove while lighting it.
Ensure that there is adequate fuel in the tank. It is generally better to start with the tank about three-quarters full. Stoves with pumps are very sensitive to too much fuel; some air in the tank is required, or the stove is likely to flare up alarmingly.
Clearing the jet
Pressure stoves will not work if the jet is blocked. Most newer stoves have a self-pricking device which operates when the valve is turned beyond the fully open position. Alternatively, use an external pricker to ensure that the jet is clear. Carry a pricker if required, packed so as to protect the fine wire.
The lighting procedure depends on the type of stove. There are three main types:
- stoves without pumps
- stoves with pumps, but without lighting regulators (e.g. most MSR models)
- stoves with pumps, and with a lighting regulator (e.g. many Coleman and Optimus models).
Stoves without pumps
The following steps are required:
- Preheat the stove, achieved by burning a fuel in the cup below the burner. There are a number of fuelling options:
- Use an eye dropper to fill the cup below the burner about two-thirds full with fuel (methylated spirit is generally recommended, but Shellite can be used with care).
- Pour a small amount of fuel into the cup below the burner. This is quicker, but has the danger of spilling fuel.
- Use part of a solid-fuel block (e.g. metatab) in the cup below the burner.
- Use fuel from the tank of the stove. This can be done through expansion if the tank is warmed. Turn the valve one-quarter on and if fuel does not flow from the jet, wrap warm hands around the tank. When the cup is about two-thirds full, close the valve. Removing the filler cap and blowing into the tank is not recommended, as the fuel is poisonous and has a very nasty taste. There is also a chance that you may forget to replace the filler cap before igniting the stove.
- Check that the valve is closed, that the filler cap is tightly screwed down, that there is no spilt fuel and that the fuel bottle is tightly stoppered and well away from the stove.
- Ignite the fuel in the priming cup.
- Allow this fuel to almost burn out, then open the valve a small amount. The burner should immediately ignite with a blue flame.
- If the priming fuel has burnt too low and the burner does not ignite, a hissing sound of vapourised fuel flowing through the jet should be heard. Immediately ignite this with a match at the burner.
- If there is no hissing sound, either the jet has not been opened far enough, the jet is blocked, or insufficient heat has been applied to the tank. In the last case, an intermittent yellow flame may occur. Unless this flame shows immediate signs of turning blue, close the jet, allow the stove to cool a little, and begin again.
- If the jet lights with a luminous yellow flame, liquid (rather than vapourised) fuel is burning. Close the valve and then repeat the preheating procedure.
Stoves with pumps, but without lighting regulators (e.g. most MSR models)
These stoves also require preheating by burning a fuel in a cup below the burner. The procedure is as follows:
- Pump the stove with the recommended number of strokes, but note that this can be influenced by factors such as the amount of fuel in the tank, the air temperature, and whether the stove is cold or has been used recently.
- Place preheating fuel in the cup below the burner (as described above).
- Light this fuel and allow it to burn almost away.
- Open the valve.
- Light the escaping vapourised fuel at the burner, if it does not light from the preheating fuel.
- If the burner lights with a luminous yellow flame, liquid, rather than vapourised fuel is burning. Close the valve, and repeat the preheating procedure. Additional pressure may also be required.
Lighting stoves with pumps and lighting regulators (e.g. many Coleman and Optimus models)
These stoves do not require preheating by burning priming fuel, but are generally more sensitive to the number of pump strokes. The procedure is:
- Pump the recommended number of strokes.
- Open the lighting regulator to the ‘light’ position.
- Light the burner.
- When burning steadily with a bright blue flame, move the lighting regulator to the ‘run’ position.
Adjust the valve (if one is fitted) to the required position for operation.