Connecting and disconnecting a cooling loop from a refrigeration system

A control system for controlling the flow of refrigerant between a refrigeration system and a cooling loop within a semiconductor processing chamber such that leakage of refrigerant is inhibited when connecting or disconnecting said refrigeration system from said cooling loop, said control system comprising:

• an inlet valve configured to selectively isolate or couple a supply path for supplying refrigerant from said refrigeration system with an inlet of said cooling loop;
• an outlet valve configured to selectively isolate or couple a return path for returning refrigerant to said refrigeration system with an outlet of said cooling loop;
• a compressor that compresses refrigerant provided to the supply path;
• a refrigerant collection valve configured to selectively isolate or couple a refrigerant collection path to said cooling loop, the collection path providing a path from said cooling loop to said compressor;
• a pressure sensor for determining a pressure of refrigerant in said cooling loop;
• an input for receiving cooling loop disconnect and connect commands;
• and
• control circuitry configured to receive signals from said pressure sensor and said commands from said input and to generate control signals for controlling the opening and closing of said inlet, outlet and refrigerant collection valves in response thereto, wherein said control circuitry is configured in response to receipt of said cooling loop disconnect command to:
• control said inlet valve and said outlet valve such that they are closed;
• control said refrigerant collection valve to be open;
• and
• direct the refrigerant from the cooling loop, through the collection valve and into the collection path while the inlet valve and the outlet valve are closed and the collection valve is open.