Error 23 / Pressure Fault
Various CPAP Machine
Severity: CriticalWhat Does This Error Mean?
Error 23 means the CPAP machine cannot deliver the prescribed pressure. The hose may be blocked, the filter may be clogged, or the motor is failing. Check the hose and filter first.
Affected Models
- ResMed AirSense 10
- ResMed AirSense 11
- Philips DreamStation
- Most CPAP machines
Common Causes
- Air hose kinked or blocked
- Air filter clogged with dust
- Hose connection not sealed properly
- Motor wearing out
- Water in the hose from the humidifier
How to Fix It
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Check the air hose for kinks or blockages.
Straighten the hose and blow through it to check for obstructions.
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Replace the air filter.
CPAP filters should be replaced every 1-2 months. A clogged filter restricts airflow and triggers pressure errors.
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Check all connections — hose to machine and hose to mask.
An air leak at a connection point prevents proper pressure delivery.
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Empty any water from the hose.
Condensation (rainout) can pool in the hose and partially block airflow. Disconnect and drain the hose.
Frequently Asked Questions
How often should I replace CPAP filters?
Disposable white filters: every 2-4 weeks. Reusable grey filters: wash monthly, replace every 6 months.
What is rainout?
Rainout is condensation forming inside the CPAP hose when warm humidified air cools. A heated hose prevents rainout.