Hitachi RAK-25NH5 RAK-35NH5 DC Inverter AC Service Manual PDF

Description

Hitachi RAK-25NH5 RAK-35NH5 DC Inverter AC Service Manual PDF DOWNLOAD

Description

This official Hitachi Service Manual provides complete technical service documentation for the RAK-25NH5 and RAK-35NH5 DC Inverter wall-type room air conditioners, paired with RAC-25NH5 / RAC-35NH5 outdoor units.

Designed strictly for service personnel, this manual explains mechanical construction, inverter electronics, refrigerant flow, control logic, wiring, PCB layouts, and fault diagnosis required for professional installation, maintenance, and repair.

✅ Models Covered

Indoor Units

• RAK-25NH5

• RAK-35NH5

Outdoor Units

• RAC-25NH5

• RAC-35NH5

Type: DC Inverter, Wall-Mounted
Power Supply: 1-Phase, 220–240V, 50Hz
Refrigerant: R410A (Factory specified)

📂 Detailed Contents & Bookmarks Breakdown

🔹 1. Specifications

• Cooling & heating capacities (BTU/h & kW)

• Input power & current ranges

• Indoor & outdoor unit dimensions

• Net weights

• Refrigerant charge quantities

• Operating temperature limits

🔹 2. Safety During Repair Work

• Electrical isolation procedures

• Semiconductor (IC) handling standards

• ESD protection methods

• Insulation resistance testing

• Grounding requirements

🔹 3. Installation Standards

• Indoor & outdoor unit clearances

• Maximum / minimum piping length

• Height difference limitations

• Drain hose insulation requirements

• Piping directions & sealing points

🔹 4. Construction & Dimensional Diagrams

• Indoor unit exploded layout

• Outdoor unit mechanical drawings

• Mounting plate references

• Airflow path & drain routing

🔹 5. Main Parts & Components

• Thermostat operating values (cooling/heating ON–OFF points)

• DC fan motor specifications

• Compressor specifications

• Motor voltages & resistance values

• Electronic expansion valve details

🔹 6. Wiring & Circuit Diagrams

• Complete indoor/outdoor wiring diagram

• Power circuit & inverter drive layout

• Compressor & fan motor connections

• Thermistor & sensor circuits

• Remote controller circuit diagram

🔹 7. Printed Wiring Board (PWB) Layouts

• Indoor main PWB

• Receiving PWB

• Outdoor main PWB

• Connector identification & markings

🔹 8. Block Diagrams

• Indoor microcomputer control logic

• Outdoor inverter control block

• Communication between indoor & outdoor units

• Sensor feedback loops

🔹 9. Operating & Control Logic

• Basic operation modes (AUTO / COOL / HEAT / DRY / FAN)

• Auto mode judgement by room & outdoor temperature

• Fan speed control logic

• Defrost control logic

• Sleep operation control

🔹 10. Refrigerating Cycle Diagram

• R410A refrigerant flow

• Compressor, expansion valve & heat exchanger operation

• Cooling & heating cycle explanation

🔹 11. Auto Swing & Airflow Control

• Horizontal & vertical deflector operation

• Auto swing motor control

• Position limits & protection logic

🔹 12. Service Call Q & A

• Abnormal noise explanation

• Restart delay logic

• Temperature limitation conditions

• Frost & defrost behavior clarification

🔹 13. Troubleshooting

• No operation faults

• Poor cooling or heating

• Sensor & thermistor faults

• Inverter protection trips

• Wiring & PCB failure diagnosis

🔹 14. Parts List & Exploded Diagrams

• Indoor unit parts

• Outdoor unit parts

• Electrical components

• Mechanical assemblies

• OEM part numbers

📄 File Details