Regular Use: When a gas canister is the right way up, evaporation of the liquefied gas normally takes place inside the canister. When evaporation occurs inside the canister the remaining liquefied gas in the canister is cooled by the evaporation process. This cooling inside the canister reduces gas pressure. But this isn’t usually a problem in above-freezing temperatures.
Inverted Canister Mode: In very cold weather, by inverting the canister (see picture above) liquified gas flows directly to the stove by way of the pre-heat tube. Evaporation occurs inside the pre-heat tube and not in the canister itself. By removing the evapouration from inside the canister, to inside the pre-heat tube, gas pressure inside the gas canister is maintained.
See our video of Dr. Mark Hines demonstrate using the KOVEA Spider in inverted canister mode to melt snow in Alaska
The diagram on the left shows how liquified gas is heated when using inverted canister mode with a KOVEA Spider:
- Cold liquefied gas moves along the fuel tube to the stove.
- When it enters the reheat tube (2) the liquified gas evapourates
- The gas then flows down the tube under pressure (3) and mixes with air when leaving the nozzle.
- The fuel-air mix then feeds the flame (4) which keeps the reheat tube (2) hot, so it can evapourate further incoming liquefied gas