Mitsubishi Electric Diagnostics & Fault Manuals
Mitsubishi Ecodan air-to-water heat pumps, Zubadan flash injection circuit maintain heating capacity down to -28°C.
Equipment Models
Hardware families produced by Mitsubishi Electric
Indexed Error Codes for Mitsubishi Electric
Machine-verified error code diagnostic walkthroughs
Compressor Overcurrent Lockout
Error U6 designates an outdoor unit compressor overcurrent trip. The inverter driver circuit detected current exceeding safe operational thresholds (typically >20-28A peak depending on chassis size) across the DC bus or U/V/W output phases, tripping the Intelligent Power Module (IPM) protection lockout.
Compressor Overcurrent Trip
The outdoor unit inverter board detected an instantaneous current draw exceeding safety thresholds (typically >23A-28A peak) through the compressor power module (IPM), triggering an immediate protective shutdown to prevent catastrophic component failure.