All canister stoves suffer a performance drop in cold weather. The colder the fuel, the lower the vapor pressure, and the lower the burner output. As far as the fuel, the output pressure in any canister stove is governed by the temperature of the gas inside the canister. As temperature drops, so does pressure. The result can be noticeably longer boil times and difficulty lighting the burner with the built-in piezoelectric ignitor. Jetpower’s lower firing rate reduces canister cooling and increases performance. Jetpower fuel, with propane, helps to mitigate cold weather problems.
When temperatures drop below freezing, canisters typically need to be kept warm in a coat pocket or sleeping bag so they’re ready to use. We suggest that you keep the canister in a warm pocket between uses and remove it immediately prior to heating your food. Insulating the canister by not setting it on a cold surface also helps. We have had mountaineers use Jetboil stoves up to 8,000 m (26,000 ft.) on Mt. Everest and love them. The pressure in the canister is directly proportional to ambient temperature and as the canister gets colder, the pressure drops and therefore the heat output from the burner drops. However, by keeping the canister warm before use, it is possible to use the stove with reasonable performance even when the ambient temperatures are at and below 0 Fahrenheit.
Placing the canister on or in a small piece of foam to keep it insulated from snow will also help. Altitude in itself is not so much of a problem: the pressure difference between the canister and the environment is also greater for any given temperature, so the effective gas flow rate is higher even when the canister is cold. The reduced oxygen causes the burner to burn richer, which is also helpful in the cold. Finally we do suggest that you always carry an extra canister and keep it warm to swap out with a cold one when necessary and always carry matches or lighter as a backup.
If you are looking to use your cooking system in temperatures colder than 45 degrees Fahrenheit, please check out our MiniMo , Sumo and Joule cooking systems. These systems feature our advanced Jetboil Regulator Technology to deliver consistent heat output down to 20° F (-6° C).