E557 (Red ON, Green Blink, Yellow OFF) — Option code mismatch among indoor units (DPM only)

What does E557 mean?

The outdoor unit's PCB LED displays E557 when there is a discrepancy in the option code settings among multiple indoor units, specifically for DPM (Digital Power Module) systems. Consistent settings are crucial for coordinated operation.

• Incorrect option code settings on one or more indoor units
• Configuration error during installation or service

Click steps to track your progress.

1. 1

   Turn off the main power to the entire system at the circuit breaker.

2. 2

   Carefully check the option code settings for each indoor unit against your system's configuration documentation.

3. 3

   Ensure all indoor units have consistent and correct option codes set.

4. 4

   Restore power and try operating the system again. If the issue persists, contact a qualified technician for assistance.