During maintenance LCW may be shut off to individual branch circuits at the individual power supplies located on the gantry platform. If it is necessary to work on the balcony regulator LCW may be shut off at the valves located on the east side of the hall where the main LCW feed and return lines enter. When shutting down any LCW circuit branch or main you must close the supply side first (Failure to do so can trap up to 300 psi in the circuit). The return side must also be closed before service to prevent the 50 psi return pressure from back-feeding the system. Water (at 50 psi) left in the system can be drained to the nearest floor drain by attaching a hose to the drain valve located at the supply and return manifolds, on each gantry platform rack.
Before pressure is reapplied drain valves must be shut. If the main supply valves at the wall were closed then the bypass and shunted test valves should be opened, as for loss of site LCW listed above. Open the return valve first to bring the system up to return pressure then slowly open the manual supply valve. Always check the system for leaks after any maintenance.