The primary driver for pressurizer replacement is a plant's desire to reduce or eliminate downtime due to pressurizer heater sleeve leaks or other Alloy 600 leaks that have plagued the industry for some time. A number of plants have already made the decision to replace their pressurizers; others are giving replacement serious consideration. Replacement pressurizers (RPZRs) eliminate Alloy 600 nozzles, thereby eliminating the downtime.