Which activity is NOT part of aggressive maintenance scheduling for B28 systems?

• A. Routine checks, cleaning, and replacement of seals, valves, and detectors
• B. Skipping or delaying replacements on worn components
• C. Regularly testing alarms and controls
• D. Replacing worn components in a timely manner

Answer: (B)

Aggressive maintenance scheduling is about staying ahead of wear and failures by actively inspecting, cleaning, and replacing components before they degrade or fail. For B28 systems, this means routinely checking and cleaning seals, valves, and detectors to maintain tightness and reliability, and regularly testing alarms and controls so safety systems will respond correctly when needed. It also means replacing worn components promptly to prevent leaks, improper operation, or unexpected shutdowns.

Skipping or delaying replacements on worn components is not part of this proactive approach. Delaying replacements allows degraded parts to continue in service, increasing the risk of leaks of flammable refrigerant, loss of control, or a triggering of a hazardous condition. Keeping worn parts in service undermines safety and reliability, which is exactly why timely replacement is emphasized in aggressive maintenance.