Startup Logic For Refrigeration System

A refrigeration system comprising:

• a compressor having a first stage and a second stage;
• a heat rejecting heat exchanger having a fan drawing ambient fluid over the heat rejecting heat exchanger, the heat rejecting heat exchanger including an intercooler and a gas cooler, the intercooler coupled to an outlet of the first stage and the gas cooler coupled to an outlet of the second stage;
• an unload valve coupled to an outlet of the intercooler and a suction port of the first stage;
• a flash tank coupled to an outlet of the gas cooler;
• a primary expansion device coupled to an outlet of the flash tank;
• a heat absorbing heat exchanger coupled to an outlet of the primary expansion device, an outlet of the heat absorbing heat exchanger coupled to the suction port of the first stage;
• and
• a controller for executing a startup process including at least one of:
• controlling the fan speed to reduce refrigerant heat loss in the heat rejecting heat exchanger;
• controlling the unload valve to direct refrigerant from the intercooler to the suction port of the first stage;
• and
• controlling the primary expansion device to restrict flow of refrigerant to the heat absorbing heat exchanger.