Mine is electronic. Its usually on electric for plugging in. For propane, just flip rocker switch to dsi and it makes heat, no pilot light to deal with. Reefer is Norcold propane/110. When at campground plugged in it automatically changes to 110. When unplugged/ automatically switches to propane and indicator light changes from green to yellow. We run on propane going down the road. If propane goes out, light will change to red. This unit works great, even in the 110 degrees in AZ, Ca, Co, etc rock hard freezer and cold reefer comp. My 12v/110 Norcold never got that cold in hot weather. Had to use fans to keep fresh foods cool enough.
They still make the RV water heaters with standing pilot lights.
Don't tell my wife that. I'll have to get one....