Context: I am not a fridgy, I work with electronics. I would love to answer my question by tearing open a dozen different aircon units, but I’m sorely lacking in that department.
Question: Are there some optional components or fancier materials that are simply too expensive to use in the lower end aircons; but are used in the higher efficiency expensive units? The range of COP/EER I see advertised is wild, from 2 to 6 or so.
I already vaguely understand that these things help efficiency:
- Bigger indoor & outdoor coils with more metal in them (working fluids get returned hotter/colder gives better carnot efficiency)
- Operating compressor at its optimal power level (I believe they have an efficiency vs power curve with a single peak, so it’s better to use a bigger compressor if you need more power output)
- Inverter control instead of on/off control (most situations, but technically some use cases will have them on par)
- Choice of refrigerant (but that seems to be controlled in my market, I have not seen many options)
Is there anything else they change? Or is that most of the difference?
Definitely. Absolute scams. They deserve the “0 energy stars” ratings I’ve seen printed on their boxes.
My family bought one of those for one of my grandparents. On a 35degC day it was only able to cool the room by a few degrees and it was still humid inside.
Converting them into dual-hose systems would be so simple (almost free) to the manufacturer, but instead they rely on deceiving buyers with a promise of something that is not delivered.