E43
Max Indoor Units Exceeded
Mitsubishi Electric · R410A Systems
What does E43 mean?
The number of indoor units connected to a single outdoor unit exceeds the system's specified design capacity. This will prevent proper communication and operation, potentially leading to system instability.
Repair Steps
- 1
Count the number of physically connected indoor units and compare this against the outdoor unit's specified maximum capacity.
- 2
Verify system design against Mitsubishi Heavy Industries technical documentation for the specific outdoor unit model and configuration.
Verified technical data. Last updated: March 2026
Source: Mitsubishi Electric R410A Systems