On this page
Asset Type
Manufacturer
Model
What This Guide Helps With
Troubleshoot wet loads after a completed drying phase caused by loading, packaging, drainage, door position, water retention, environment, or equipment performance.
Step-by-Step Troubleshooting
1. Protect Patients and Sterile Processing Workflow
Treat a wet load as unsuitable for sterile storage or clinical use according to facility infection-prevention procedures.
Do not release instruments simply because the cycle displayed completion. Reprocess affected items as required by facility policy.
If the sterilizer repeatedly produces wet loads, remove it from routine clinical processing until the cause is identified.
Expected outcome: Questionable instruments are withheld from use and an alternate verified sterilizer is used when needed.
2. Confirm the Exact Wet-Load Condition
Determine whether:
- The entire load is wet.
- Only certain packs or trays are wet.
- Moisture is on the chamber walls only.
- The problem occurs with all cycles or certain load types.
- The drying phase actually completed without interruption.
Inspect the load immediately after the reported condition when practical.
Expected outcome: The moisture pattern and affected load type are clearly identified, helping distinguish loading problems from sterilizer problems.
3. Review Load Size and Arrangement
Inspect how instruments, trays, and packaged items were loaded.
Check for:
- Overloading.
- Items packed tightly together.
- Packages touching chamber surfaces.
- Stacked items that restrict air movement.
- Containers positioned so water can collect.
- Mixed loads arranged in a way that traps condensate.
Do not treat this as operator retraining only; document whether the physical loading condition could reasonably prevent drying.
Expected outcome: The load is arranged with adequate spacing and drainage. If correcting the load arrangement produces a dry load on repeat testing, troubleshooting can stop.
4. Inspect Packaging and Containers
Verify that packaging materials, pouches, trays, or wrapped sets are appropriate for the sterilization process being used.
Look for:
- Excessively dense wrapping.
- Damaged packaging.
- Folded or compressed pouches.
- Containers retaining water.
- Instrument geometry that traps condensate.
Use a known-good representative load when comparison is useful.
Expected outcome: Packaging and containers permit normal steam exposure and drying. If a known-good load dries correctly, the sterilizer may be functioning normally.
5. Verify Chamber Drainage
With the sterilizer cool and safe to inspect, check accessible chamber and drain areas for:
- Standing water.
- Debris.
- Obvious blockage.
- Residue.
- Foreign material.
- Water that does not appear to drain normally.
Do not probe or disassemble internal drain plumbing beyond approved maintenance access.
Expected outcome: The chamber drains freely with no visible obstruction. If clearing an approved accessible obstruction restores drying performance, troubleshooting can stop after verification.
6. Inspect Door and Gasket Condition
Inspect the door and accessible gasket surfaces for:
- Debris.
- Damage.
- Deformation.
- Poor seating.
- Evidence of steam leakage.
- Moisture concentrated near the door seal.
A sealing problem can affect pressure, exhaust, and drying performance.
Expected outcome: Door and gasket surfaces are clean, intact, and properly seated. If correcting an accessible sealing issue restores drying, troubleshooting can stop after verification.
7. Verify the Cycle and Drying Selection
Confirm that the cycle selected is appropriate for the load and that the intended drying phase was actually enabled and completed.
Review any user-selectable drying options without changing restricted configuration parameters.
Check whether the cycle was interrupted, canceled, or the door was opened before drying was complete.
Expected outcome: The correct cycle and intended drying process are confirmed. If an incorrect selection caused the problem, repeat with the correct approved cycle and stop troubleshooting if the load dries normally.
8. Evaluate Room and Cooling Conditions
Check the sterilizer environment for conditions that may promote condensation, including:
- Unusually cool room temperatures.
- Strong airflow directed at the sterilizer.
- High humidity.
- Placement near HVAC discharge.
- Rapid handling of hot packs in a cool environment.
Do not attribute repeated wet loads to the room without verifying sterilizer performance.
Expected outcome: No obvious environmental condition explains the moisture, or the condition is corrected and repeat testing confirms normal drying.
9. Perform a Controlled Test With a Known-Good Load
Process an appropriate known-good representative test load using the correct cycle.
Observe:
- Cycle completion.
- Exhaust behavior.
- Drying phase completion.
- Chamber condition afterward.
- Presence and location of remaining moisture.
Do not use the test load for patient care unless all facility release requirements are satisfied.
Expected outcome: The known-good load exits acceptably dry. If it does, focus on original load arrangement or packaging and stop equipment troubleshooting.
10. Escalate Persistent Drying Problems
If loading, packaging, drainage, gasket condition, cycle selection, and environment have been ruled out and a known-good load remains wet, stop external troubleshooting.
Possible remaining categories include:
- Internal exhaust or venting problem.
- Heating or drying-system performance problem.
- Internal plumbing restriction.
- Temperature or pressure-control issue.
- Door or chamber sealing problem requiring service-level evaluation.
Expected outcome: The sterilizer is removed from service when reliable drying and sterilization performance cannot be demonstrated.
If the Problem Persists
Common external causes have been ruled out. Remove the sterilizer from service, label it Out of Service, and send it for repair or bench evaluation.
Evaluate the unit using appropriate Midmark documentation and approved test equipment. Repairs, adjustments, or configuration changes affecting steam, exhaust, temperature, pressure, or drying should be performed only by qualified personnel.
Return the sterilizer to service only after complete cycle testing and any required sterilization-performance verification have been successfully completed.
Knowing when to stop external troubleshooting is proper troubleshooting.
Clinical Use Tip
A completed cycle does not make a wet package acceptable for sterile storage; follow facility reprocessing requirements whenever load dryness is questionable.
Work Order Documentation (CCR Method)
CCR = Complaint, Cause, Resolution
Complaint
What was reported by the clinical staff.
Example:
"Sterile Processing reported that instrument packs remained wet after the Midmark M9 completed the drying phase."
Cause
What was observed during troubleshooting.
Example:
"Clinical Engineering found the test load was packed tightly with several pouches positioned so condensate could not drain effectively."
Resolution
What action was taken.
Example:
"Corrected the load arrangement, repeated the cycle with proper spacing, and verified that the drying phase completed with the load acceptably dry."
Helpful Details to Include (If Known)
- Load type.
- Packaging or container type.
- Whether entire load or individual items were wet.
- Cycle selected.
- Whether drying completed or was interrupted.
- Chamber drainage condition.
- Door and gasket condition.
- Room airflow or environmental conditions.
- Known-good load results.
- Moisture location after testing.
- Final device status.
Final Thought
Wet loads must be treated as a patient-safety and infection-control concern. Rule out loading, packaging, drainage, sealing, cycle selection, and environment before assuming an internal drying failure, then escalate and document clearly.
That is successful troubleshooting.