Short answer: worth it if you run the AC from a small inverter generator, an inverter/battery bank, or a weak campground pedestal. Pick one listed as compatible with your AC model and compressor type.
| If you need… | Look for |
|---|---|
| Run AC on a 2,000–2,500 W inverter generator | Soft start sized for your AC's BTU and compressor |
| Run AC from batteries/inverter | Soft start + right-sized inverter (calculator) |
| Two AC units on 30 A | Soft starts on both, plus load management |
| Variable-speed / inverter AC | Usually already soft starting; check before buying one |
| DIY vs installer | Most install inside the AC shroud; follow the manufacturer's wiring guide |
Compressors briefly pull several times their running power on startup. Soft starts are commonly reported to cut that spike by roughly half or more; enter the figure your soft-start maker publishes. Then size the source with the generator calculator or inverter for RV AC.
Safety: These are general estimates, not a design. Follow your equipment manufacturer's instructions and local electrical code, and consult a qualified electrician for anything connected to shore power, a house, or high-current batteries.
Yes if you want to run AC on a small generator, inverter or weak shore power. If you only use strong 50 A hookups, you may not need one.
No. It only lowers the startup surge; running consumption stays the same.
Often a 13,500 BTU AC can start on a 2,000–2,500 W inverter generator with a soft start, depending on the unit, altitude and heat. Check the generator's rated running watts.
As an Amazon Associate, RVSolarMath earns from qualifying purchases.