Mitsubishi Air Conditioner Error Code E.OV1

E.OV1 indicates a regenerative overvoltage trip that occurred during an acceleration phase. The internal main circuit DC bus voltage exceeded its specified safe value due to regenerative power or a surge voltage. The unit shuts down automatically to protect the inverter power module and related components. A technician will need to evaluate acceleration parameters, the Pr.22 stall prevention setting, and the incoming power supply quality.

No, the unit has shut down as a protective measure and should not be forced back into operation without diagnosing the root cause. Repeatedly restarting the system without addressing the underlying overvoltage condition can cause progressive damage to the inverter power module and other main circuit components. Contact a qualified technician to evaluate the fault before resuming normal operation.

Repair costs vary widely depending on the root cause. If the fix involves only adjusting inverter parameters such as Pr.22 or acceleration settings, labor costs are typically in the range of $75 to $200. If hardware components such as DC bus capacitors, a braking resistor, or surge suppression equipment need to be replaced, total costs including parts and labor can range from $200 to $800 or more depending on the unit and component availability.

Start by checking the Pr.22 stall prevention operation level setting and the configured acceleration time to ensure they are appropriate for the connected load. If the parameter settings appear correct, inspect the incoming power supply for surges or line transients. If adjustments to parameters do not resolve the fault, a qualified technician should inspect the DC bus capacitors and evaluate whether a braking resistor or surge suppressor is needed.

A reset may clear the fault code temporarily, but if the underlying condition causing the overvoltage has not been corrected, the E.OV1 error will return. Simply resetting without addressing parameter settings, load conditions, or power supply issues is not a lasting solution. Persistent recurrence of E.OV1 after resets indicates that a component or configuration issue requires professional attention.