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critical Della

Error Code E9

Outdoor IPM module fault — inverter power module malfunctioning.

? What Causes This

Component failures within the outdoor unit's variable speed motor control or other related electronic parts breakdowns leading to improper functioning of components responsible for managing voltage changes between indoor and outdoor compressor.

How to Fix It

Service technician should replace faulty components to regain normal system operation.

Source: page 40 of the official manual

From the manual

Manual page 40 — Della error E9

This error code appears in:

Della 048 MS T1159k