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Reader Cheryl V. has an interesting question:

“Have you heard of a device that helps start your AC slowly so that a 13500 [BTU] can run on a Honda 2000 generator?” she asks. “I forgot to ask about it at Alumapalooza.”

Now that summer is in full swing, temperatures are high both inside and outside our Airstreams and AC maintenance and operational practices are top of mind. Experts at Outside Interests have pondered Cheryl’s question, and think she’s asking about a “soft start” capacitor, like the Dometic SmartStart II.

It doesn’t actually “start the AC slowly”, but acts like a boost battery to take some of the initial load off the power source (usually a generator) when the air conditioner compressor starts up.

The short answer to the question? It’s not a good idea to try to run your air conditioner on a single Honda 2000 generator, even with this device.

Your RV air conditioner pulls a great deal of power when it ramps up upon starting, and can easily overload the typical 2000 watt RV generator—resulting in the generator shutting down or possible damage to the air conditioner.

A start capacitor stores power to help with this initial load, but it’s not able to make miracles happen. Even with a start capacitor, a 2000-watt generator is not a good match for the typical Dometic air conditioner installed on an Airstream. Dometic recommends at least a 3500-watt generator. Many Airstreamers have success with 3000-watt generators, or two 2000-watt generator running in parallel.

You might have read online that some folks allow their ACs to run from a 2000-watt generator, but please be careful. This goes into the same category as running the air conditioner on a 15-amp plug. It will work…until it doesn’t. And a burned-out air conditioner is an expensive repair. Look carefully at all recommendations, guidlines and warnings printed in the documents supplied with any product of this kind.

Hope that helps, Cheryl. Keep cool! Check out this other Outside Interests article about air conditioning for more information.

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