At the heart of every marine air conditioning unit is a compressor that is driven by alternating current (AC). All single phase AC motors need a boost or “kick” to get them moving initially, and this results in a much higher current draw than is required to simply keep the motor running. Although it only lasts less than a second, this surge, or inrush current can often be three times or more the running current, and typically neccesitates the installation of much larger generators than would be required just to keep compressors running. Starting medium/large air conditioning units from portable generators or inverters is often impossible unless this inrush current is reduced somehow.
The EasyStart from Coastal Climate Control, is a solid state add-on device that reduces compressor starting loads to less than half the locked-rotor rating. There are two models, both for use on single phase units of either 115v or 230v, 50 or 60 Hz. EasyStart 364 is suitable for compressors from 5,000 Btu to 36,000 Btu, and EasyStart 368 is for larger compressors of from 37,000 Btu up to 72,000 Btu. Both models are housed in protective enclosures, and connection is by a simple four-wire hook-up. Full instructions are included. Both models require a “learning period” of 7 or more starts before starting current is fully minimized.

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