Use and Care Manual
Table Of Contents
- Foreword
- Safety Notice
- CONTENTS
- Safety Notice on Maintenance
- Safety Notice on Operation
- 1 Product Introduction
- NOTE: 1 Ton =12000Btu/h = 3.517kW 1.2 Electrical Parameters
- 2 Control
- 3 Troubleshooting
- 3.1 Wiring Diagrams
- 3.2 PCB Layout
- 3.3 Error Code
- 3.4 Troubleshooting
- 3.4.1 “E1” Compressor High Pressure Protection
- 3.4.2 “E3” Compressor Low-pressure Protection, Refrigerant Shortage Protection, Refrigerant Recovery Mode
- 3.4.3 “E4” Compressor Air Discharge High-temperature Protection
- 3.4.4 “F2” Condenser Temperature Sensor Error
- 3.4.5 “F3” Outdoor Ambient Temperature Sensor Error
- 3.4.6 “F4” Discharge Temperature Sensor Error
- 3.4.7 “F6” ODU Tube Temperature Sensor Error
- 3.4.8“EE” ODU Memory Chip Error
- 3.4.9 “H4” Overload
- 3.4.10 “H5” IPM Protection
- 3.4.11 “H6” DC Fan Error
- 3.4.12 “H7” Driver Out-of-Step Protection
- 3.4.13 “HC” PFC Protection
- 3.4.14 “Lc” Startup Failure
- 3.4.15 “P0” Driver Reset Protection
- 3.4.16 “P5” Over-Current Protection
- 3.4.17 “P6” Master Control and Driver Communication Error
- 3.4.18 “P7” Driver Module Sensor Error
- 3.4.19 “P8” Driver Module High Temperature Protection
- 3.4.20 “PA” AC Current Protection
- 3.4.21 “Pc” Driver Current Error
- 3.4.22 “PL” Bus Low-Voltage Protection
- 3.4.23 “PH” Bus High-Voltage Protection
- 3.4.24 “PU” Charge Loop Error
- 3.4.25 “ee” Drive Memory Chip Error
- 3.5 Failures Not Caused by Errors
- 4 Maintenance
- Appendices
- 1 Resistance/Temperature Lists of Temperature Sensors
- 1.1 Voltage List of 15 KΩ Temperature Sensors (including ODU temperature sensors)
- 1.2 Voltage List of 20 KΩ Pipeline Temperature Sensors (including temperature sensors for defroster, IDU and ODU pipes)
- 1.3 Voltage List of 50 KΩ Discharge Temperature Sensors (including discharge air temperature sensor)
- 2 Temperature/Pressure List of Refrigerant
- 3 Operation Tools
MRCOOL DC INVERTER COOLING ONLY CONDENSING UNIT
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3.4.20 “PA” AC Current Protection
Error display:
ODU mainboard LED displayer
Error judgment condition and method:
If input current value exceeds the set protection value, then it can be judged that AC current protection
occurs and system will shut down for protection.
Possible reason:
■System is heavy-loaded and compressor current is too large.
■Grid voltage is abnormal.
■PFC module is damaged.
■Drive board PFC current sampling circuit element is damaged or drive chip PFC current sampling AD terminal is
abnormal.
Troubleshooting
：
3.4.21 “Pc” Driver Current Error
Error display:
ODU mainboard LED displayer
Error judgment condition and method:
After power charging, if offset voltage average is detected to exceed 12.5% of 1.65V in 1s, then it can be
judged that current detection (or current sensor) circuit is faulted. System will shut down for protection.
Possible reason:
■Current detection (or current sensor) sampling circuit element is abnormal.
■Drive chip compressor current sampling AD terminal is badly welded or short-circuited.