The SoftStartRV Soft Start for RV AC Units # SSR54FR is designed to work with single-phase air conditioner units. If you remove the shroud there's a tag on the compressor that should state if your unit is single-phase or three-phase.
If you have an Advent Air unit then you'll want the Start Capacitor for Advent Air RV Air Conditioners # ACMSCKIT instead.
If you were replacing the start capacitor on a Furrion unit you would want the # FR45FR for a 14,500 BTU unit and the # FR65FR for... view full answer...