Good idea to bench test, whatever it is.
Low volts? What is the high volts?
Belt driven or electric compressor, what you choose to start up needs to make, break, and carry the load in amperes. Thermostat, relays, contactors, solenoids, inverter, transformers, coolant sensors.
It's sometimes chosen, more practical, to use a control circuit (low voltage), and a power circuit(high voltage), for controls and for power hungry consumer loads.