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Asset Type
Manufacturer
Advanced Sterilization Products (ASP)
Model
What This Guide Helps With
Troubleshoot moisture-related cycle interruption caused by wet instruments, damp packaging, condensation, chamber moisture, or persistent sensing and vacuum problems.
Step-by-Step Troubleshooting
1. Protect the Load and Maintain Processing Continuity
Do not release instruments from a moisture-interrupted or otherwise incomplete cycle.
Move urgent loads to another approved sterilization pathway if available.
Expected outcome: Patient-use instruments remain limited to loads that have completed a validated process.
2. Confirm the Moisture-Related Condition
Review the exact displayed message and determine when the cycle stops.
Ask whether the problem:
- Occurs with every load
- Occurs only with certain instrument sets
- Began after washing or rapid turnaround
- Occurs after a particular tray or lumen device is loaded
- Persists with an otherwise dry verification load
Expected outcome: The moisture event is correlated with either the load or the sterilizer.
3. Inspect the Load for Visible Moisture
Examine instruments, trays, packaging, lumens, hinges, cavities, and other areas where water can remain trapped.
Do not assume the load is dry simply because exterior surfaces appear dry.
Expected outcome: All items intended for processing are visibly dry and were prepared using the applicable instructions.
If wet items are found, remove and dry them appropriately before retesting.
4. Inspect the Chamber and Accessories
Check accessible chamber surfaces, trays, and racks for:
- Condensation
- Water droplets
- Damp surfaces
- Residual cleaning fluid
- Wet accessories
- Recent spill or cleaning activity
Expected outcome: The chamber and loading accessories are dry before the next cycle.
5. Check Load Density and Arrangement
Verify that the load is not packed so densely that moisture remains trapped or normal chamber conditioning is impaired.
Check that instruments and packaging are positioned according to applicable processing requirements.
Expected outcome: The load is appropriately arranged and permits normal processing.
6. Identify Load-Specific Patterns
If the problem is intermittent, compare:
- One instrument set versus another
- One tray versus another
- Lumen versus non-lumen items
- Recently washed versus fully dried items
Avoid repeated full loads until the pattern is understood.
Expected outcome: A specific load, tray, or preparation condition is either identified or ruled out.
If one load consistently causes the problem while approved dry verification loads do not, troubleshooting can stop after the load-processing cause is corrected and verified.
7. Check Room Conditions
Review whether unusually high room humidity, temperature changes, HVAC interruptions, or cold instruments entering a warmer environment could be contributing to condensation.
Do not alter sterilizer configuration to compensate for an uncontrolled room condition.
Expected outcome: The sterilizer is operating in a stable environment without obvious condensation-producing conditions.
8. Run an Appropriate Dry Verification Load
Once visible moisture and load preparation issues are corrected, run an approved verification cycle with a properly prepared dry load.
Expected outcome: The unit completes the full cycle without a moisture-related interruption.
If successful and the problem does not recur, troubleshooting can stop.
9. Compare Persistent Moisture Events With Other Symptoms
If dry verification loads still fail, determine whether there are also:
- Vacuum failures
- Repeated conditioning attempts
- Door sealing concerns
- Unusual chamber behavior
- Other system messages
This can indicate that the apparent moisture problem is related to a broader vacuum, sensing, or system condition.
Expected outcome: A persistent sterilizer-side problem is identified for escalation rather than repeated load adjustments.
10. Remove From Service if Dry Loads Continue to Fail
If the moisture condition occurs with verified dry loads after external causes are ruled out, remove the sterilizer from service.
Do not bypass moisture detection or attempt unauthorized sensor adjustment.
Expected outcome: An unreliable sterilization process is prevented from returning to patient-use workflow.
If the Problem Persists
Common external causes such as wet instruments, damp packaging, chamber moisture, load density, and room conditions have been ruled out.
A persistent problem may involve sensing, vacuum performance, chamber conditions, software, or another internal service-level subsystem.
The device should be:
- Removed from service
- Labeled Out of Service
- Sent for qualified repair or service evaluation
- Evaluated using ASP documentation and approved test equipment
- Repaired or configured only by qualified personnel
After service, complete all required functional and sterilization performance verification before clinical return.
Knowing when to stop external troubleshooting is proper troubleshooting.
Clinical Use Tip
Pay particular attention to lumens, hinged devices, and recessed areas because retained moisture may not be obvious during a quick visual inspection.
Work Order Documentation (CCR Method)
CCR = Complaint, Cause, Resolution
Complaint
What was reported by the clinical staff.
Example:
"Sterile Processing reported repeated moisture-related cycle interruptions on the STERRAD 100NX."
Cause
What was observed during troubleshooting.
Example:
"Clinical Engineering found residual water in a recently washed instrument tray while the sterilizer chamber was dry and otherwise operated normally."
Resolution
What action was taken.
Example:
"The wet tray was removed and fully dried, and a properly prepared verification load completed the full sterilization cycle successfully."
Helpful Details to Include (If Known)
- Exact moisture-related message
- Cycle phase
- Specific trays or instruments involved
- Visible moisture location
- Load density
- Chamber condition
- Recent washing or cleaning
- Room HVAC or humidity concerns
- Result with dry verification load
- Vacuum-related symptoms
- Final device status
Final Thought
Moisture faults often originate with preparation rather than the sterilizer itself. Verify the load, chamber, arrangement, and environment carefully before assuming a sensor or vacuum failure. Escalate persistent dry-load failures and document exactly what was tested.
That is successful troubleshooting.