Puritan Bennett 980

Exhalation System or Expiratory Filter Fault

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Asset Type

Ventilator

Manufacturer

Puritan Bennett

Model

980

What This Guide Helps With

Troubleshooting exhalation-system alarms, expiratory filter restriction, condensate buildup, poor exhaled-volume measurement, abnormal PEEP, or failed exhalation-related SST tests.

Step-by-Step Troubleshooting

1. Ensure Patient Safety First

Do not troubleshoot an exhalation-system fault while the Puritan Bennett 980 is actively supporting a patient.

Transfer the patient to another verified ventilator or approved ventilation method. Confirm effective ventilation, oxygenation, and alarm operation on the replacement equipment.

An exhalation restriction or valve problem may interfere with pressure relief, PEEP control, exhaled-volume monitoring, and the patient’s ability to exhale.

Expected outcome: The patient is safely supported without relying on the affected ventilator.

Continue Clinical Engineering troubleshooting only after the PB980 has been removed from patient use.

2. Confirm the Exact Reported Fault

Review the alarm message, diagnostic code, event log, and SST history. Determine whether the complaint involves:

The PB980 SST separately evaluates exhalation-valve performance, expiratory filter or compartment occlusion, circuit resistance, leaks, and pressure sensing.

Expected outcome: The specific failure and affected SST test are identified and documented.

3. Inspect the Expiratory Limb

Disconnect the test circuit and inspect the entire expiratory limb for:

Replace the circuit or expiratory limb with a known-good compatible assembly when its condition is uncertain.

The ventilator may detect expiratory-limb occlusion caused by condensate, secretions, kinked tubing, or excessive downstream resistance.

Expected outcome: The expiratory pathway is open, dry, correctly assembled, and free of unnecessary restrictions.

If this resolves the fault and the ventilator subsequently passes testing, stop troubleshooting.

4. Inspect the Expiratory Filter

Open the exhalation-filter compartment and verify that the correct adult/pediatric or neonatal filter configuration is installed.

Inspect the filter for:

Confirm that the filter sits fully in its guides and that the patient-side connection aligns correctly with the filter door.

The exhaled-gas pathway passes through the condensate vial, exhalation filter, exhalation flow sensor, and exhalation valve before reaching the exhaust port.

Expected outcome: The correct filter is properly installed and shows no evidence of obstruction or damage.

5. Reseat the Filter and Secure the Door

Remove and reinstall the expiratory filter according to the approved configuration.

Confirm that:

The PB980 filter compartment uses a dedicated door and latch to retain the filter assembly.

Expected outcome: The assembly is secure, correctly aligned, and sealed.

6. Check the Condensate Vial

Inspect the vial for accumulated liquid, contamination, cracks, damaged threads, or an incomplete seal.

Empty the vial before the liquid reaches the maximum fill line. Reinstall it fully and verify that it reaches its mechanical stop. The manufacturer warns that excessive condensate can enter the ventilator, and removal of the vial may cause pressure loss or a disconnect alarm.

Do not drain or remove the vial while the ventilator is connected to a patient.

Expected outcome: The vial is empty or below its limit, undamaged, and sealed correctly to the filter.

7. Replace the Expiratory Filter

Install a known-good, compatible expiratory filter assembly.

Use the appropriate configuration for the selected patient category. Do not reuse a disposable filter, substitute an unapproved filter, or attempt to clean a component designated for single use.

When replacing a reusable assembly, confirm that it has been processed, inspected, dried, and released according to the manufacturer’s instructions and facility infection-control policy.

Expected outcome: The alarm clears or the failed filter-related test passes with the replacement filter.

If the replacement filter corrects the problem, document the restricted, wet, damaged, or improperly seated filter as the cause and stop troubleshooting.

8. Inspect the Exhalation Compartment and Exhaust Area

With the filter removed, visually inspect accessible areas of the compartment without internal disassembly.

Look for:

Do not insert tools, compressed air, swabs, or cleaning fluids into internal pressure or flow passages.

A blocked exhaust port or excessive resistance at the exhaust can contribute to exhalation-path occlusion.

Expected outcome: No external obstruction, liquid intrusion, or physical damage is found.

If liquid has entered the ventilator, remove the device from service and escalate for bench evaluation.

9. Install a Known-Good Test Circuit

Connect a complete known-good circuit, including the correct expiratory filter, condensate vial, humidification configuration, and accessories.

Confirm that the selected patient type and circuit configuration match the installed components. Remove unnecessary adapters or accessories that could add resistance.

Expected outcome: The external circuit and filter assembly are eliminated as possible causes.

10. Run the Full SST

Allow the ventilator to reach the required operating condition, then run the complete Short Self Test using the installed test circuit and accessories.

Pay particular attention to:

The Exhalation Filter Test checks for filter and exhalation-compartment occlusion, while the Exhalation Valve Performance test evaluates and calibrates valve behavior.

Expected outcome: All SST tests pass without Alert, Override, or Failure status.

Do not return the ventilator to service based only on an overridden SST alert. The manufacturer warns that overriding an SST alert may allow operation outside stated accuracy specifications.

11. Perform a Controlled Functional Verification

After SST passes, connect an approved test lung or ventilator analyzer and verify:

Use more than one representative setting when required by facility procedure.

Expected outcome: The ventilator completes repeated breaths with stable exhalation, accurate monitoring, and no alarms.

If the fault returns, stop testing and escalate.

If the Problem Persists

If a known-good circuit, expiratory filter, condensate vial, and correct assembly do not resolve the problem, common external causes have been ruled out.

The remaining fault may involve the:

The ventilator should be:

A failed SST is considered a critical condition, and the ventilator cannot be used for normal ventilation until the failed test is corrected and SST passes.

Knowing when to stop replacing external components and escalate an internal exhalation fault is proper troubleshooting.

Clinical Use Tip

Never remove an expiratory filter or condensate vial while the PB980 is supporting a patient. Move the patient to another verified ventilator before opening the exhalation compartment or running SST.

Work Order Documentation (CCR Method)

CCR = Complaint, Cause, Resolution

Complaint

What was reported by the clinical staff.

Example:
"Respiratory Therapy reported an exhalation-system fault and repeated failure of the PB980 SST Exhalation Filter Test."

Cause

What was observed during troubleshooting.

Example:
"Inspection found a moisture-saturated expiratory filter and condensate at the maximum fill level, creating excessive expiratory-path resistance."

Resolution

What action was taken.

Example:
"Removed the ventilator from service, replaced the expiratory filter, emptied and reseated the condensate vial, installed a verified test circuit, and completed SST and functional testing with all results passing."

Helpful Details to Include (If Known)

Final Thought

Exhalation faults require immediate attention because restrictions or valve problems may affect pressure release, PEEP regulation, and exhaled-volume monitoring. Begin with the circuit, moisture, filter, vial, and installation before suspecting an internal valve or sensor failure. Return the ventilator to service only after a complete SST and controlled functional verification pass, and clearly document what was found and corrected.

That is successful troubleshooting.

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