On this page
Asset Type
Manufacturer
Model
What This Guide Helps With
This guide assists Clinical Engineering in troubleshooting situations where a Fresenius 5008 HD machine triggers dialysate conductivity or mixing alarms. These alarms may indicate improper dialysate composition, flow irregularities, or sensor misreadings. The focus is on checking external, easily verifiable causes first to ensure patient safety before escalating to internal system issues or repair.
Step-by-Step Troubleshooting
Verify Patient Safety First
- Ensure no patient is currently on the affected machine.
- If a patient is connected, move them to a standby or functioning HD machine before troubleshooting.
Check Water Supply and Quality
- Confirm that the machine’s water inlet valves are fully open.
- Verify that RO water supply meets conductivity and purity specifications.
- Inspect for kinks, leaks, or blockages in the water inlet tubing.
Why it matters: Improper water quality directly affects dialysate conductivity.
Inspect Concentrate Connections
- Ensure acid and bicarbonate concentrate lines are correctly connected and free of air bubbles.
- Check that concentrate bags are not expired or contaminated.
Why it matters: Incorrectly connected or empty bags can trigger conductivity errors.
Examine Dialysate Preparation and Flow
- Verify that the machine’s mixing chamber is free of residue or obstructions.
- Confirm that all valves related to dialysate mixing are operational and correctly seated.
Why it matters: Blocked or misaligned valves affect proper dialysate composition.
Check Conductivity Sensors
- Inspect the conductivity probe for fouling, residue, or misalignment.
- Clean the sensor according to Fresenius-approved procedures.
- Reinstall securely and retest calibration.
Why it matters: A dirty or misaligned sensor can give false alarms even if mixing is correct.
Perform Machine Self-Check/Calibration
- Run the machine’s automatic dialysate conductivity calibration routine.
- Note any errors or failures during the procedure.
Why it matters: Confirms whether the system recognizes proper conductivity after external corrections.
Review Recent Maintenance or Changes
- Check if any recent service, part replacement, or water quality issues coincide with alarm onset.
- Document observations for troubleshooting history.
If the Problem Persists
If external factors (water supply, concentrate connections, sensors) are verified and alarms continue:
- Remove the machine from service.
- Label as Out of Service.
- Escalate for internal repair or Fresenius service evaluation.
Clinical Engineering should not attempt internal board-level repairs, as improper handling can risk patient safety and machine integrity.
Clinical Use Tip
- Never attempt dialysate troubleshooting with a patient attached.
- Always confirm proper dialysate mixing before reconnecting patients.
- Maintain logs of any alarms and actions taken for safe patient care continuity.
Work Order Documentation (CCR Method)
CCR = Complaint, Cause, Resolution
Complaint
What was reported by the clinical staff.
Example:
“Machine displays dialysate conductivity alarm intermittently during treatment.”
Cause
What was observed during troubleshooting.
Example:
Observed low dialysate conductivity due to air in concentrate lines and fouled conductivity sensor.
Resolution
What action was taken.
Example:
Cleared air from lines, cleaned conductivity probe, ran calibration successfully, verified proper mixing. Machine returned to service.
Helpful Details to Include
- Outlet tested and water quality confirmed.
- Concentrate lines inspected and swapped if needed.
- Conductivity probe cleaned and recalibrated.
- Machine self-test completed successfully.
- Final status: Machine operational and returning proper dialysate conductivity.
Final Thought
Patient safety, logical troubleshooting, and proper documentation are the foundation of Clinical Engineering work. Addressing simple external causes first often prevents unnecessary repair escalation and ensures reliable HD treatment.
That is successful troubleshooting.