Believe me, with the onslaught of technology that has been thrown into this sector during the last decade, there is no shortage of inverter-driven designs heading to the scrap yards every day. With the continued penetration of inexpensive, proprietary mini-split units into the market, the number of techs blaming "that SAMSONIC JUNK unit" they have no idea how to fix is increasing the number of purely hackable units being condemned. They are even showing up on craigslist and freecycle!
From a hacking or experimental standpoint, it is not a major undertaking to rig up multiple compressors in parallel. Like you said, a suction accumulator is needed to prevent slugging the compressor/compressors, especially during defrost. Some attention must be taken to plumb the compressors for proper oil flow. Extra control circuitry must be devised to avoid overcurrent or overpressure events from happening. But it has all been done before, you just need to know where to look for information.
|