Transcritical refrigerant vapor compression system with charge management

A refrigerant vapor compression system comprising:

• a primary refrigerant circuit including a refrigerant compression device, a refrigerant cooling heat exchanger for passing refrigerant received from said compression device at a high pressure in heat exchange relationship with a cooling medium, a refrigerant heating heat exchanger for passing refrigerant at a low pressure refrigerant in heat exchange relationship with a heating medium, and a primary expansion device interdisposed in the primary refrigerant circuit downstream of said refrigerant cooling heat exchanger and upstream of said refrigerant heating heat exchanger;
• a refrigerant-to-refrigerant heat exchanger economizer having a first refrigerant pass disposed in the primary refrigerant circuit downstream of said refrigerant cooling heat exchanger and upstream of said primary expansion device and a second bypass disposed in an economizer circuit refrigerant line;
• a flash tank disposed in the primary refrigerant circuit downstream of the first refrigerant pass of said refrigerant-to-refrigerant exchanger and upstream of said primary expansion device, said flash tank defining a separation chamber wherein refrigerant in a liquid state collects in a lower portion of said separation chamber and refrigerant in a vapor state in a portion of said separation chamber above the liquid refrigerant;
• a secondary expansion device disposed in the primary refrigerant circuit in operative association with and upstream with of said flash tank;
• an refrigerant vapor bypass line establishing refrigerant flow communication between an upper portion of said separation chamber of said flask tank and a suction pressure portion of said primary refrigerant circuit downstream of said refrigerant heat absorption heat exchanger;
• and
• a bypass flow control valve interdisposed in said evaporator bypass line, said bypass flow control valve having a first open position whereat refrigerant vapor may pass through said evaporator bypass line and a second closed position whereat refrigerant vapor is blocked from passing through said evaporator bypass line.