ResMed Error 5: What It Means & What to Do
Quick answer
ResMed Error 5 is a manufacturer-documented CPAP fault. Start with the exterior checks below and follow the user guide for the exact model; do not open the device.
Equipment: CPAP · Fault type: error · Severity: high
What Error 5 means
ResMed Error 5 is documented as a CPAP device fault. The available service documentation contains additional internal diagnostic detail, which is separated below because it is not a consumer repair procedure.
Meaning varies by model or source
- AirSense 11 - service and technical guide doc 398011/2 (manufacturer): Motor over-voltage; faulty power supply, faulty motor or faulty main PCB - replace faulty part
- AirSense 11 - ResMed official user guide: System fault, Error X: an unrecoverable error has occurred on the device. Contact your care provider; do not open the device.
What you can safely check
- Stop therapy and read the complete displayed message before doing anything else.
- Disconnect power using the device power connector or power supply; do not open the enclosure.
- If overheating is implicated, move the device away from heat and allow it to cool before reuse.
- Inspect the external air filter for blockage and replace it only as the user guide directs.
- Inspect the air tubing for blockage, kinks, damage, or water.
- Where relevant, verify that the humidifier tub or side cover is seated correctly and dry.
- Reconnect power and perform ONE restart only when the manufacturer's user guide allows it for that message.
- If the fault returns, therapy is unavailable, or the message is unrecoverable, contact your CPAP equipment provider or authorized service center. Follow your care provider's guidance if therapy cannot be used.
What not to do
- Do not open the enclosure or replace internal electronics, blower hardware, sensors, or boards yourself.
- Do not perform calibration, enter undocumented service menus, bypass safety mechanisms, or change therapy-pressure settings to work around the fault.
Technician-level interpretation
Service documentation may describe internal diagnosis or component replacement. These are not consumer procedures.
- Service-record meaning: Motor over-voltage; faulty power supply, faulty motor or faulty main PCB - replace faulty part
- AirSense 11 - service and technical guide doc 398011/2 (manufacturer): Motor over-voltage; faulty power supply, faulty motor or faulty main PCB - replace faulty part
Which models are covered?
- AirSense 11
If the message returns
Contact your CPAP equipment provider or authorized service center. If therapy is unavailable, follow the guidance from your care provider rather than improvising a replacement setting.
Sources
- ResMed AirSense 11 Series Service and Technical Guide (doc 398011/2), Troubleshooting guide - numbered error messages — manufacturer-service-manual; verified 2026-08-29
- ResMed AirSense 11 User Guide (Americas, official): Error 4 = hot environment/blocked filter/water in tubing - cool, replace filter, power-cycle; all other numbered Errors = unrecoverable device fault, contact care provider, do not open — manufacturer-support; verified 2026-08-29
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CPAP Machine Error: Safe Checks Before Calling Your Provider