Abstract: The disclosed apparatus includes a condensing chamber (CC) that maintains a volume of a condensate obtained from vapor emitting from a vessel, for example a reactor pressure vessel (RPV). The condensing chamber is connected to a reference leg (RL), a variable leg (VL) and a vapor or steam leg (SL). RL connection provides a flow path for the CRD drive water system backfill to flow into the CC and overflow into the VL. The excess backfill and/or condensate will be returned to the vessel, typically at a point below the liquid level within the vessel. Non-condensable gases will thereby be returned from the CC to the RPV in a substantially continuous manner, thereby tending to prevent the introduction of non-condensable gas enriched liquid from the CC into the RL and improving the tolerance and reliability of the level measurements and/or reducing thermal stresses on the various CC connections.

Abstract: The disclosed apparatus includes a condensing chamber (CC) that maintains a volume of a condensate obtained from vapor emitting from a vessel, for example a reactor pressure vessel (RPV). The condensing chamber is connected to a reference leg (RL), a variable leg (VL) and a vapor or steam leg (SL). RL connection provides a flow path for the CRD drive water system backfill to flow into the CC and overflow into the VL. The excess backfill and/or condensate will be returned to the vessel, typically at a point below the liquid level within the vessel. Non-condensable gases will thereby be returned from the CC to the RPV in a substantially continuous manner, thereby tending to prevent the introduction of non-condensable gas enriched liquid from the CC into the RL and improving the tolerance and reliability of the level measurements and/or reducing thermal stresses on the various CC connections.