Lower priced AC Soft Start

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Senior Member
Nov 7, 2022
Vessel Name
Vessel Make
Cargile Cutter
I purchased a 2500w inverter generator last year. Op tested it yesterday for the 1st time on my 5th wheel's Dometic roof AC. I have a similar roof AC on my 28' trailer trailer. I plan to use the genset on the boat when cruising. As expected when I turned on the AC it's compressor bogged down the genset for maybe 2 seconds then the genset recovered and the AC worked fine. I suppose this will happen every time the compressor starts. I am aware of the benefits of Soft Start/Easy Start caps in this situation. I have priced them on Amazon for a couple of years. They are now priced around $300 but a lot of cheaper alternatives are now available. A few around $130, one as low as $60. All from China. Not an issue if they work. Question is, has anyone installed one of these cheaper alternatives in their roof top AC? Thanks
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Since it sounds like your generator is marginal in starting your A/C I would first try a few no cost, low cost solutions.

The two second lug down period may be due to the generator switching from inverter mode to non inverter mode (fixed 3,600 rpm) where it finally starts. If you can set it to non inverter mode, try it, it may start fine.

A cheap solution may be Supco’s capacitor. It has a relay that disconnects the extra capacitor after it helps start the A/C. See https://www.supplyhouse.com/Supco-S...mia1cfuEPZRiL1GV3QOmmMnvYVl9zvaBoCFvYQAvD_BwE

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