<< Are controls for natural gas and propane the same? >>
yes, except for different diaphragms in the main control and different orifice
in the pilot control. In other words, they use the same body casting. Control
manufacturers usually have kits available for switching from one gas to the
other. Been there, done that some years ago, not difficult at all with the
The propane orifice is smaller than the NG. This means you need new ones. Get
them from the furnace maker if you can, maybe start by calling their customer
service for a parts list, advice on conversion. Good luck.