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
23
There are LED indicators on the main board of the indoor unit, which are used to display the operating status
and malfunction information of the unit.
LED indicator
Color
Function
Power Indicator
Red
Indoor unit main board is powered on, Power Indicator is on.
Running Indicator
Green
After detecting the indoor fan turn-on signal, the running indicator
light is on, when detecting the indoor fan turning-off signal, the
running indicator light is off. When detecting a system failure, the
running indicator light flashes.
Different running indicator flashing light means different system failure.
malfunction
Running Indicator status
Remark
Indoor Jumper cap failure
Light out 3S then flash once
Flash means light on 0.5S then light out 0.5S
Indoor fan failure
Light out 3S then flash twice
Indoor tube temperature
sensor failure
Light out 3S then flash four
times
3.4 Troubleshooting
3.4.1 “E1” Compressor High Pressure Protection
Error display: ODU mainboard LED displayer
Error judgment condition and method:
It is judged through the action of high pressure switch. If the high pressure switch is cut off, it is judged that
high pressure is too high and the system stops operation for protection.
Possible reason
：
■Cut-off valve of ODU is not fully opened;
■High pressure switch is abnormal;
■Outdoor or indoor fan is not working properly;
■Ambient temperature is too high;
■Refrigerant charging amount is too much;
■System pipeline is blocked