Daikin RXG25K2V1B User Manual

Service
Manual
[Applied Models]
z Inverter Pair : Heat Pump
Inverter Pair
Wall Mounted Type J-Series
SiBE041012_A

Daikin RXG25K2V1B Specifications

General

Category	Air Conditioner
Model	RXG25K2V1B
Cooling Capacity	2.5 kW
Heating Capacity	3.2 kW
Power Supply	220-240V, 50Hz
Refrigerant	R32
Indoor Unit Weight	9 kg

Summary

1. Introduction

1.1 Safety Cautions

Be sure to read the following safety cautions before conducting repair work. Items are classified into Warning and Caution.

Part 1 List of Functions

Part 2 Specifications

1. Specifications

Provides detailed technical specifications for indoor and outdoor units, including capacity, power, airflow, and dimensions.

Part 3 Printed Circuit Board Connector Wiring Diagram

1. Indoor Unit

2. Outdoor Unit

Part 4 Function and Control

1.10 ECONO Operation

1.11 INTELLIGENT EYE Operation

1.12 Inverter POWERFUL Operation

3. Control Specification

3.2 Frequency Control

3.3 Controls at Mode Changing / Start-up

3.4 Discharge Pipe Temperature Control

3.5 Input Current Control

3.6 Freeze-up Protection Control

Manages operating frequency to prevent indoor heat exchanger freezing during cooling.

3.7 Heating Peak-cut Control

Regulates frequency upper limit during heating to prevent abnormal high pressure.

3.10 Defrost Control

3.11 Outdoor Electronic Expansion Valve Control

3.12 Malfunctions

Covers detection of overcurrent, overload, and refrigerant shortage.

Part 5 Operation Manual

2.2 AUTO · DRY · COOL · HEAT · FAN Operation

2.5 INTELLIGENT EYE Operation

2.6 POWERFUL Operation

2.8 ECONO Operation

Part 6 Service Diagnosis

1. Troubleshooting with LED

Guides on troubleshooting based on LED indicators on the indoor and outdoor units, and identifies potential error causes.

2. Problem Symptoms and Measures

Lists common operational problems and their corresponding measures for diagnosis and resolution.

3. Service Check Function

4.1 Error Codes and Description

Provides a comprehensive list of error codes displayed on the remote controller and their associated descriptions and reference pages.

4.2 Indoor Unit PCB Abnormality

Troubleshooting guide for indoor unit PCB abnormalities, including supposed causes and checks.

4.3 Freeze-up Protection Control or Heating Peak-cut Control

Addresses issues related to freeze-up protection in cooling and peak-cut control in heating.

4.4 Fan Motor (DC Motor) or Related Abnormality

Troubleshooting steps for DC fan motor abnormalities, including rotation speed and supposed causes.

4.5 Thermistor or Related Abnormality (Indoor Unit)

Guides for diagnosing indoor unit thermistor or related abnormalities based on input voltage.

4.6 Front Panel Open / Close Fault

4.7 Signal Transmission Error (between Indoor Unit and Outdoor Unit)

Diagnoses signal transmission errors between indoor and outdoor units, checking wiring and PCB integrity.

4.8 Unspecified Voltage (between Indoor Unit and Outdoor Unit)

Troubleshooting for unspecified voltage issues between indoor and outdoor units, checking model compatibility.

4.9 Outdoor Unit PCB Abnormality

Troubleshooting for outdoor unit PCB abnormalities, covering 25/35 class and 50 class units.

4.10 OL Activation (Compressor Overload)

Addresses issues related to compressor overload (OL activation), including thermistor and valve checks.

4.11 Compressor Lock

Troubleshooting steps for compressor lock detection, considering overcurrent and waveform generation.

4.12 DC Fan Lock

Diagnoses DC fan lock errors by checking rotation speed detected by the Hall IC.

4.13 Input Overcurrent Detection

Details the detection of input overcurrent by checking the current value while the compressor is running.

4.14 Four Way Valve Abnormality

Troubleshooting for four-way valve abnormalities, checking thermistor function and temperature differences.

4.15 Discharge Pipe Temperature Control

Explains the control of discharge pipe temperature and its impact on compressor frequency.

4.16 High Pressure Control in Cooling

Details high-pressure control activated in cooling when outdoor heat exchanger thermistor exceeds limits.

4.17 Compressor System Sensor Abnormality

Troubleshooting for compressor system sensor abnormalities, checking DC current and voltage before compressor start.

4.18 Position Sensor Abnormality

Diagnoses compressor start-up failure detected through the position detection circuit.

4.19 DC Voltage / Current Sensor Abnormality (25/35 Class)

Troubleshooting for DC voltage/current sensor abnormalities based on compressor running frequency and input current.

4.20 CT or Related Abnormality (50 Class)

Diagnoses CT or related errors by checking compressor running frequency and CT input current.

4.21 Thermistor or Related Abnormality (Outdoor Unit)

Troubleshooting for outdoor unit thermistor abnormalities identified by thermistor input voltage.

4.22 Electrical Box Temperature Rise

Detects electrical box temperature rise by checking the radiation fin thermistor with the compressor off.

4.23 Radiation Fin Temperature Rise

Detects radiation fin temperature rise by checking the radiation fin thermistor with the compressor on.

4.24 Output Overcurrent Detection

Detects output overcurrent by checking current flow in the inverter DC section.

4.25 Refrigerant Shortage

Identifies refrigerant shortage through power consumption, discharge pipe temperature, and pressure difference.

4.26 Low-voltage Detection or Over-voltage Detection

Detects low-voltage or over-voltage conditions in the power supply to the unit.

4.27 Signal Transmission Error on Outdoor Unit PCB (50 Class Only)

Troubleshoots communication errors between the main microcomputer and PM1 on the outdoor unit PCB.

5.1 Thermistor Resistance Check

Details the procedure to check thermistor resistance by measuring it with a tester against a temperature table.

5.2 Fan Motor Connector Check

5.3 Power Supply Waveforms Check

5.4 Electronic Expansion Valve Coil Check

5.5 Four Way Valve Performance Check

5.6 Inverter Unit Refrigerant System Check

5.7 “Inverter Checker” Check

Explains how to use an inverter checker to diagnose compressor startup or overcurrent issues.

5.8 Rotation Pulse Check on the Outdoor Unit PCB

5.12 Main Circuit Short Check

Part 7 Removal Procedure

Part 8 Trial Operation and Field Settings

1. Pump Down Operation

Explains the procedure for conducting pump down operation when relocating or disposing of the unit.

2. Forced Cooling Operation

Details the conditions, start, command frequency, and end of the forced cooling operation.

3. Trial Operation

Guides on performing trial operation to ensure all functions work properly, including setting temperatures and modes.

Part 9 Appendix