Daikin Error Code E3: High Pressure Switch Activated

Severity: Warning
Type: digital display
Where to look: remote controller

Warning: Your Daikin HVAC system has encountered a high-pressure issue and has shut down to prevent damage. Call a professional for repair.

How to Fix Daikin Code E3

Check and replace your air filters if they are dirty. This can help restore normal airflow and pressure in your system.
If your system is low on refrigerant, do not attempt to add more yourself. Call a professional HVAC technician to diagnose and repair the leak.
If the issue persists after checking and replacing your air filters, call a professional HVAC technician to diagnose and repair the issue.

How to Reset Daikin Code E3

Turn off the unit using the remote control or wall controller.
Turn off the circuit breaker for the outdoor and indoor units. Wait 60 seconds.
Restore power at the breaker.
Turn the unit on with the remote control. If the error returns, the fault needs professional diagnosis.

What does E3 mean?

The Daikin E3 error code indicates that the high-pressure switch has been activated. This switch is designed to protect your HVAC system from excessive pressure, which can cause damage to the compressor and other components. When this error occurs, your Daikin system will shut down to prevent further issues. The most common causes for this error are refrigerant leaks, clogged filters, or a faulty expansion valve.

Affected Models

Replacement Parts

Part	OEM Number	Est. Cost
High-Pressure Switch	4728N1A001	—
Expansion Valve	4728N1A002	—

Related Codes on Same Models

Code	Description	Severity
A1	Indoor PCB Defective	Warning
A3	Drain Level System Fault	Warning
A5	Freeze-Up/Overheat Protection	Warning
A6	Fan Motor Lock/Overcurrent	Warning
C4	Heat Exchanger Thermistor Fault	Warning
C9	Suction Air Thermistor Fault	Warning
E1	Outdoor PCB Defective	Warning
E4	Low Pressure Switch Activated	Warning
E5	Compressor Motor Lock	Warning
E6	Standard Compressor Motor	Warning