Fuel tank vent valve for heaters

摘要: A jerrycan holds liquid fuel. cap for the includes an air vent valve assembly having umbrella-shaped check valve. The is sensitive to a pressure differential between interior of and atmosphere. As fuel dispensed from jerrycan, volume chamber within increases, thereby decreasing in creating vacuum. vacuum causes rate at which decrease. dislodges when becomes less than atmosphere additional introduced into jerrycan. fills expanded chamber, increasing pressure, eliminating causing increase.