ResMed Error 004: What It Means & What to Do
Quick answer
On AirSense 10, ResMed's user guide associates Error 004 with a hot environment, a blocked air filter, or water in the air tubing. Allow the device to cool, check the external filter and tubing, and disconnect then reconnect the power supply once as the guide directs; a recurring fault needs service.
Equipment: CPAP · Fault type: error · Severity: high
What Error 004 means
ResMed Error 004 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 10 — ResMed official user guide: Device may have been left in a hot environment, the air filter may be blocked, or there may be water in the air tubing. Allow the device to cool, check the filter and tubing, then disconnect and reconnect the power supply to restart it.
- AirSense 10 — authorized ResMed service reference: The service reference describes Error 004 as main PC-board over-temperature and directs persistent faults to service.
Model-specific meaning
- AirSense 10 — Error 004: Hot environment, blocked external filter, or water in air tubing; persistent faults need service.
Error 004 versus Error 4
The repository keeps these model-specific records at their existing URLs. The source record here is for AirSense 10 and uses Error 004; a separate AirSense 11 record uses Error 4. Confirm the exact model and displayed code before applying the checks.
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: For AirSense 10, ResMed's official user guide lists a hot environment, a blocked air filter, or water in the air tubing as possible causes of Error 004. An authorized service reference describes the underlying condition as main-board over-temperature; the two readings are retained as model/source-specific context rather than silently merged.
Which models are covered?
- AirSense 10
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.
Related ResMed CPAP faults
High Leak Detected · Tubing Blocked · High Temperature Fault
Sources
- ResMed AirSense 10 device with humidifier — official user guide — manufacturer-support; verified 2026-09-03
- ResMed AirSense 10 Problems and Error Messages — authorized service reference — authorized-service-center; verified 2026-09-03
Related CPAP guides
CPAP High Leak: What to Check · CPAP Machine Error: Safe Checks Before Calling Your Provider