No hot water heater, furnace, stove or other appliance for furnishing heat, steam, hot air or hot water shall use as fuel gas, compressed gas or liquefied petroleum gas, other than that furnished by a public utility furnishing this service under the jurisdiction of the Illinois commerce commission. "Liquefied petroleum gas" shall mean any material which is composed predominantly of any of the following hydrocarbons, or mixtures of them: propane, propylene, butane (normal butane or isobutane) and butylenes. (1981 Code)