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
7
2.2 Control Mode
2.2.1 Based Control
2.2.1.1 Compressor Control
When cooling mode is turned on, indoor fan will run for a while before the compressor starts. Under different
modes, the compressor can only be stopped after running for some time (special cases excluded). This is to
protect the compressor from frequent start or stop. Once the compressor is stopped, it must not be restarted right
away. Please wait for a few minutes.
2.2.1.2 Outdoor Fan Control
This series air conditioner has two types of outdoor units: one with a single fan and the other with double
fans. The outdoor fan can run at the highest level 10 and the lowest level 1. By controlling the speed of outdoor
fan, the unit can achieve cooling at low temperature. In fan mode, outdoor fan will not work.
2.2.2 Special Control
Oil Return Control
If the unit is running at low frequency for a long time, system will enable oil return control. This is to lead oil in
the pipeline back to the compressor so that the compressor will not be lack of oil. Generally, the oil return takes
about 5min. The compressor running frequency will be raised to the preset oil return frequency.
2.2.3 Protection Control
2.2.3.1 High Pressure Protection Control
System will enable high pressure protection control if the high pressure switch is detected open for
continuously a little time. Under high pressure protection, system will be shut down and display error code E1.
When high pressure protection occurs for the first time, system will restore operation if the high pressure
switch is detected to be reclosed for continuously a little time. When high pressure protection occurs for the
second time in a certain time period, system will not restore operation. You need to manually turn off the unit and
clear the error before restarting up the unit. (If high pressure protection occurs frequently, please send for
professional personnel to repair.)