Instructions: Adding refrigerant fluid to system At CERN: M.Galuska, V. Vinš, V. Vacek page 1 Present Cooling System installed at Bldg. 175, CERN – August 2003 Instructions: Adding refrigerant fluid to system tank with C3F8 coolant tank liquid valves pressure regulation valves tank-connecting hose condenser inlet assembly condenser window vacuum pump auxiliary condenser cooling valve Figure 2 – Condenser temperature Figure 1 – Condenser surroundings Preliminary Conditions In the case of filling the system with coolant, it is assumed the system is shut off and all corresponding valves are in their shut-off position (see shut-off instructions). This is especially true of the silver valve of the auxiliary condenser cooling, which must be in the open position. The temperature of the condenser must be bellow the ambient room temperature – this can be checked on the display on top of the blue rack (Fig. 2). Procedure 1) Check that the silver valve (water) of the auxiliary condenser cooling is open. 2) Connect the red tank-connecting hose to the valve in the condenser inlet assembly (not in picture, on the opposite side of the pressure gauge). Make sure all the valves on the tank and the pressure regulator are closed. 3) Attach the vacuum pump to one of the free valves of the pressure regulator, and turn the pump on (power on + turn the yellow pump valve to the OPEN position). 4) Open the valves on the pressure regulator except the one that has no connection (total 3 knobs) – this will evacuate all air from the tank connection.

6) Disconnect the vacuum pump and turn it off. At CERN: M.Galuska, V. Vinš, V. Vacek page 2 5) After waiting a few minutes for the complete evacuation of the tank-condenser connecting hoses and tubes, close the valve on the pressure regulator leading to the vacuum pump. 6) Disconnect the vacuum pump and turn it off. 7) Open the liquid valve on the tank (red – also labeled “liquid”) 8) Uncap and screw clockwise the valve on the condenser inlet – this will open the valve with the red tank-connecting hose. Immediately following this, monitor the condenser window (step 9). 9) Carefully watch the liquid level in the condenser window. Close the tank valve (from step 7) well before reaching the desired level of liquid in the condenser – it will take some time for all liquid to flow through the connecting hose. Do not fill higher than to ¾ of the window! You must wait several minutes for all the liquid to flow through the hose. 10) Screw the valve on the condenser inlet counterclockwise to close the inlet valve. 11) Thoroughly check the condenser inlet valve for leaks! After verifying its tightness, recap it. 12) Close all valves on the pressure regulator. 13) Unscrew the red tank-connecting hose from the condenser inlet. This concludes the filling operation.