Will The SoftStartUp Plug-In Soft Start Run A 13.5K BTU AC With 15 Amp Shore Power

Updated 08/12/2026 | Published 08/07/2026

Question:

Will it run 13.5 BTU A/C with 15 amp shore power?

asked by: Steve

Expert Reply:

Hey Steve, thanks for reaching out. Yes, in many cases it will. The SoftStartUp Plug-In Soft Start for RV Air Conditioners # SSR64FR is specifically designed to reduce the startup surge of an RV air conditioner, which is what normally trips a 15-amp household breaker. A typical 13,500 BTU AC draws around 10 to 13 amps while running, and the SoftStartUp cuts the startup surge by nearly 50%, making it much more likely to start and run successfully on a 15-amp circuit.

That said, there isn't a guarantee because the 15-amp circuit itself is the limiting factor. If the circuit has voltage drop, a long extension cord, or other loads running at the same time, it can still trip the breaker. For the best results, plug into a dedicated 15-amp circuit with a short, heavy-gauge extension cord and turn off other RV loads like the converter, water heater, microwave, and refrigerator while the AC is running. Under those conditions, a 13.5K BTU air conditioner has an excellent chance of running on 15-amp shore power with the # SSR64FR.

Where do you usually plug in? Home driveway or older low-amp camp spots?

expert reply by: Jesse M

Steve

8/11/2026

Thanks, Jesse. I have my Airstream stored an enclosed but outdoor storage unit with 15 amp service.

Jesse M.

8/12/2026

@Steve Ok nice! Yea as long as you aren't running a bunch of other appliances at the same time, that soft start will allow your AC to start up without issue.