Click each finding in sequence, applying Module 4's troubleshooting order, to reach a supported diagnosis.

Capstone: Vacuum Degradation Investigation

Track 2: Vacuum Systems — Module 5 of 5

Applying the Complete Systematic Sequence

This capstone works through a full vacuum degradation scenario using the exact systematic troubleshooting sequence established in Module 4, demonstrating how that ordered approach — CW temperature, then CW flow, then TTD, then air removal exhaust — reliably reaches a well-supported diagnosis, even when the underlying cause turns out different from the scenario worked through in Track 1's capstone.

Working the Sequence Step by Step

The shift log opens with vacuum meaningfully worse than design expectations — the trigger condition. Following Module 4's established order, CW inlet temperature is checked first and found normal, ruling out a warming source. CW flow is checked next and also found normal — at 99% of design with healthy screen differential pressure — ruling out the reduced-flow explanation that was the actual root cause in Track 1's capstone scenario.

Same sequence, different answer: this is an important point about systematic troubleshooting — following an identical, well-structured investigative order doesn't mean every scenario reaches the same conclusion. Track 1's capstone found reduced CW flow as the root cause; this scenario's data specifically rules that same factor out. The value of a systematic sequence lies in reliably following the evidence wherever it actually leads, not in producing a predetermined answer.

Finding the Actual Cause

With CW temperature and flow both confirmed normal, the sequence moves to checking TTD — and this time, it comes back elevated, 3°F above baseline. This is the first abnormal finding in this particular investigation, and per Module 3's discussion of surface condenser heat transfer, it specifically points toward reduced tube-side heat transfer effectiveness — tube fouling, rather than an inadequate CW supply issue.

Completing the Investigation, Not Stopping Early

Following Module 4's explicit caution against stopping the moment one explanation is found, air removal exhaust flow is still checked despite the elevated TTD finding already providing a likely explanation. This final check comes back normal, adding confidence that air in-leakage isn't a significant simultaneous contributing factor — strengthening rather than complicating the tube-fouling diagnosis by ruling out an alternative explanation rather than leaving it unaddressed.

Watch for: notice how this capstone's diagnosis leads to a genuinely different corrective action than Track 1's capstone would have called for — tube cleaning here, versus screen maintenance there. This underscores why working through the full systematic sequence matters: acting on an assumed cause without confirming it through this kind of structured investigation risks addressing the wrong problem entirely, wasting maintenance effort while the actual root cause remains unaddressed.

Track 2 Complete — What's Ahead

With Track 2 complete — air removal equipment, in-leakage sources and detection, backpressure effects on turbine equipment, systematic troubleshooting, and now this applied capstone — Track 3 moves into Feedwater Heaters: LP/HP heater construction, extraction steam, drain cascading, and the TTD/DCA concepts that have already made an appearance in this track's diagnostic content.

Module Quiz

6 questions • 80% (5 of 6) required to pass