Ever seen an icy built-up outside the propane cylinder? Do not be alarmed, it can be explained by simple physics. Propane is a fossil fuel, which exists in the form of gas at standard temperature and pressure (32 °F, 1bar). However, for an easy transportation and distribution, it is bottled in cylinders at high pressure, turning propane into liquid. As per the ideal gas law (PV=nRT), pressure is directly proportional to temperature. Therefore, when the pressure inside the cylinder (due to usage) goes down, the temperature inside the cylinder too falls proportionally. Hence, as the gas gets used (typically on a high humidity day), ice formation on the outer surface of the cylinder can be experienced.
There are no safety concerns, however, if the regulator gets icy, the gas flow may get constricted extinguishing the stove/ grill or in my case, the ‘dragon’ weed burner. In case you experience these conditions, there can be two solutions – 1. If the cylinder is not near empty, then simply reduce the discharge of the gas from the cylinder, that will help maintain the pressure inside the cylinder and thereby avoiding excessive cooling; 2. In case the cylinder is near empty, it is the time to change the cylinder.
Word of caution: Propane is highly inflammable and heavier than air. Please ensure to take every standard safety precautions as described on the cylinder safety card.
P-pressure, V-volume, n- amount of gas in moles, R- gas constant, T-temperature