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Manufacturer
Model
What This Guide Helps With
Door not sealing, cycle not starting, leaks, or seal-related alarms caused by latch issues, gasket wear, or obstruction.
Step-by-Step Troubleshooting
Ensure Patient Safety First
- Do not troubleshoot while an endoscope is actively being processed for patient use.
- Remove scope and use a backup AER if needed.
- Expected: No impact to patient care workflow
- Why it matters: Incomplete disinfection poses infection risk
Verify the Reported Issue
- Attempt to close the door and start a cycle.
- Observe:
- Door does not latch
- Cycle will not start
- Seal-related alarm or leak detected
- Visible gap or resistance when closing
- Expected: Door fully closes and locks without resistance
- Why it matters: Confirms a true sealing issue vs user operation error
Inspect Door for Obstructions (Most Common Cause)
- Inspect chamber opening and door edge
- Remove debris, scope tubing, or misrouted connectors
- Ensure no packaging material or lint is caught in the seal
- Expected: Door closes smoothly with no obstruction
- Why it matters: Even small debris can prevent proper sealing
Check Door Gasket / Seal Condition
- Look for cracks, flattening, or deformation
- Check for moisture buildup, residue, or chemical deposits
- Wipe clean using approved method if contaminated
- Expected: Gasket is intact, flexible, and clean
- Why it matters: A compromised gasket prevents airtight sealing required for proper cycle operation
Verify Proper Door Alignment and Closure Technique
- Close the door slowly and firmly
- Observe if one side closes before the other
- Check for uneven gaps
- Expected: Even, flush closure across entire door surface
- Why it matters: Misalignment can prevent latch engagement and sealing
Check Door Latch / Locking Mechanism
- Listen for latch engagement when closing
- Check for loose or damaged latch components
- Attempt multiple closures to confirm consistency
- Expected: Audible/visible latch engagement
- Why it matters: If the latch does not engage, the system will not allow cycle initiation
Check for Error Messages or Alarm Codes
- Note specific alarm messages
- Clear alarms and retry cycle
- Expected: No recurring seal or door-related alarms
- Why it matters: Helps determine if issue is mechanical vs sensor-related
Inspect for Signs of Leakage During Attempted Cycle
- Look for water escaping near the door
- Check for pooling under the unit
- Expected: No leakage during operation
- Why it matters: Confirms seal failure even if latch appears functional
If the Problem Persists
If all external causes have been ruled out, the issue is likely internal (worn gasket, latch assembly failure, or door seal sensor issue).
Remove the device from service, label it Out of Service, and send for repair or bench evaluation.
Do not continue attempting to run cycles with a compromised seal.
Clinical Use Tip
Never attempt to override or force a door closed on an AER. If the door does not seal properly, move scopes to another unit to ensure proper high-level disinfection.
Work Order Documentation (CCR Method)
CCR = Complaint, Cause, Resolution
Complaint
What was reported by the clinical staff.
Example:
"Unit would not start cycle; door would not seal properly."
Cause
What was observed during troubleshooting.
Example:
"Door gasket worn and partially deformed, preventing proper chamber seal."
Resolution
What action was taken.
Example:
"Removed unit from service and sent for gasket replacement and seal integrity testing."
Helpful Details to Include (If Known)
- Door closes fully or partially
- Presence of visible debris or obstruction
- Gasket condition (cracked, flattened, intact)
- Latch engagement (yes/no)
- Any leak observed
- Alarm or error message displayed
- Final device status (in service / out of service)
Final Thought
Door and seal issues are critical in AERs because they directly affect disinfection effectiveness. Always start with simple mechanical checks before escalating. Recognizing when a seal is compromised and removing the device from service protects both patients and staff while preventing ineffective reprocessing cycles.
That is successful troubleshooting.