[en] Scenarios resulting from the loss of inventory control in the Primary Heat Transport (PHT) system due to loss of control to feed and bleed valves are developed here. Their consequences are also discussed. The loss of inventory control resulting in net feed flow will over pressurize the PHT system. If reactor trip is not initiated at high pressure trip set point, opening of the primary relief valves at 1631 psi g will terminate the transient. If opening of primary relief valves is also not credited, PHT pressure will increase further and will ultimately be limited by the capacity of charging pumps of about 1741 psi g. At this pressure there is very little chance of system integrity failure as PHT design operating pressure is exceeded only by a small amount. Loss of inventory control resulting in the opening of feed and bleed valves will depressurize the system. System pressure will decrease until feed flow balances the bleed flow. Resulting system pressure (1158 psi g) will be higher than the saturation pressure at the maximum system temperature. However, loss of inventory control resulting in the opening of bleed valves alone will depressurize the system rapidly and bulk boiling will take place in about 10 seconds. 10 figs.; 8 tabs. (author)