[hgerhardt]

This would be a great application for an Arduino with a simple LCD readout.

Below is what I put together to run and monitor a ground-based prototype AC system for what I eventually installed in my homebuilt airplane. The display shows PWM power to the variable-displacement compressor as well as high-side pressure and evaporator temperature. The pressure sensor being monitored (and used to modulate the compressor) is a standard GM 3-wire AC sensor and the evap temp sensor is a thermistor from a Honda.