content: What would be better is if you could have a fridge could work, on a very simple level (mechanical thermostat, physical switches, etc), without any kind of electronics.  And have a standard logic board interface that could plug in and disconnect/override/consume/control those interfaces and tap other lines for smart telemetry and diagnostics.  You can get some really useful predictive indicators from watching the phase lag on the compressor, comparing compressor on time with temperature curve, and things like that.  And if you did it all right, when you pulled the board, the fridge would work with the mechanical door switch, thermostat, and relays - no more proprietary logic board going out and taking the fridge with it.