Ductless & inverter · COMPONENT REFERENCE
Mini-split inverter and power electronics troubleshooting
Converts the supply into the controlled motor power used by variable-speed compressors. Input supply, DC link, output module and cooling are distinct diagnostic stages.
Failure causes
Choose a cause for symptoms, checks that separate it from similar faults, repair direction and verification.
Missing input or DC-link supply →A supply, connection or internal power-conversion fault prevents the drive from establishing its required operating supply.Inverter output module or IPM protection →The output stage reports an abnormal condition or cannot drive the compressor. A protection report can arise from the motor or operating conditions as well as the module.Heat-sink or electronics cooling problem →Restricted cooling or an impaired thermal interface raises power-device temperature during operation.
References and applicability
Original HVACSim explanations with manufacturer and instrument-maker references for further reading. These resources support the subject; their model-specific examples are not specifications for every system.
- Haier: Arctic Next Gen service manualAW/1U EH2VHD model examples of inverter, motor, sensor and circuit diagnostics; obtain the installed model manual.
- Daikin: 17 Series service manualModel-specific sensor and control examples; terminal values and code definitions vary.
Editorial review: 2026-09-29. Verify the current manual for the installed model.