Converting a stove from natural gas to propane involves changing internal parts to compensate for the differences in the operating pressure of the two gases. It requires installation of a conversion kit. If the kit is not available, owners should not attempt to convert the appliance.
As of 2015, manufacturers that sell within the United States clearly label appliances that allow for conversion from one type of fuel to another. Most of these appliances also include the conversion kit in the packaging. Some require the consumer to order the conversion kit directly from the manufacturer. Appliances with an NG or LP label are not convertible and often carry warning labels against attempting such conversions.
While the conversion of older stove models requires the owner only changing the orifices or drilling a larger hole in the existing orifice, the engineering of newer stoves to improve fuel efficiency and decrease emissions makes conversions more difficult. The conversion process requires changing of orifices, regulators and burners. In some cases, a stove that previously operated as a vent free model prior to conversion produces enough exhaust gases that it requires venting.
In stoves that the manufacturer designs for conversion, the process requires several steps, including converting one or more regulators, turning screws to change orifice size for each burner, removing the oven burner to make a manual adjustment and adjusting the air shutters.