Mini split decision: 120v 20 SEER vs 240v 30.5 seer with auto transformer?

[Aakelley]

Planning for the next phase of the solar install on my bus. Have 1500+ watts of panels, a growatt 3000 AIO and 10kwh of LifePO4 batteries now. Net phase is adding a mini split AC and if it performs well enough, pulling the roof top unit I have now, and adding another 1K watts of solar.

I am looking at two units for the mini split: the pioneer 12,000 BTU 20 SEER that runs on 120v and the Innovate 12,000 BTU 30.5 SEER that runs on 240V. With the later unit, I would have to get some form of auto transformer to step up the voltage since the Growatt is 120 only (and stacking a second one isn't really an option / necessary). Looking at the victron 32A or he solar edge for that.

I am wondering if there are any real world power consumption data on the two, including the draw of the auto transformer and/or if there are any calculations I could do to determine which would have the smaller energy requirements? Basically will a 50% improvement in the AC efficiency overcome the draw of a transformer?

 

[timselectric]

Transformers are pretty high efficiency. As long as you don't load them heavily and create waste heat.
That said, I would probably go with the 120v option for simplicity.

 

[Quattrohead]

KISS would be my approach too.