D Series Modular Air-cooled Scroll Chillers 
40
Overload 
protection
• 
The voltage is too high or too low
• 
The discharge pressrue is too high or too 
low
• 
The backwater temperature is too high
• 
The overloaded elment malfunctions
• 
The ambient temperateure is too high
• 
The motor and wiring terminal is short-
circuited
• 
Check the voltage which is required to 
be within the rated value ±20V and the 
exceedance of the  phase dierence to be 
within ±30%
• 
Check the discharge pressure and gure out 
why
• 
Check the backwater temperature and gure 
out why
• 
Check the electric current of the compressor
• 
Improve the ventilation
• 
Check the corresponding resistance of the 
motor and the terminal
Internal over-
temperature 
protection
• 
The voltage is too high or too low
• 
The discharge pressure is too high
• 
The entering chilled water temperature is 
too high
• 
The internal overtemperature protection 
device malfunctions
• 
Refrigerant is charged insuciently
• 
Check the voltage which is required to be 
within the allowable range
• 
Check the discharge pressure and gure out 
why
• 
Check the entering chilled water and gure 
out why
• 
Take the leakage test
Low pressure 
protection
• 
The check valve or the drier-lter is 
clogged
• 
The expanson valve malfunctions
• 
The low pressure switch malfunctions
• 
Refrigerant is charged insuciently
• 
Replace the check valve or the drier-lter
• 
Adjust or replace the expansion valve
• 
Check the low presure switch
• 
Add refrigerant
Failure to 
startup
• 
 The circuit breaker trips or the fuse is 
blown out
• 
The control circuit fails to get through
• 
There is no electric currrent
• 
High or low pressure protection acts
• 
The contact coil is blown out.
• 
Power phase is wired improperly
• 
The water system malfunctions and the 
ow switch is opened
• 
An alarm is raised on the wired controller
• 
The ON/OFF Timer is improperly set 
• 
The temperature sensor is set out of the 
set point
• 
Replace the damaged element
• 
Check the wiring of the control system
• 
Check the power supply
• 
See “Too high discharge pressure”, “Too low 
discharge pressure”, “Too high discharge 
pressure”, and “Too low discharge pressure”
• 
Replace the damaged element
• 
Rewire the power phase
• 
Check the water system
• 
Check the alarm type and take 
countermeasures
• 
Check and adjust the set point
WARNING
Without commissioning, warranty will turned invalid under the following conditions:
• 
Refrigerant leaks in that the user personally opens some valve or pipe connector. 
• 
The user personally dismantles the unit without Gree’s approval.
• 
The user personally powers the control cabinet or the compressor motor.
• 
The user personally charges oil or refrigerant to the unit.
• 
The user personally starts up the system.
• 
The user personally passes directly hot water or steam to the evaporator.  
• 
The user fails to operate the unit following the instructions covered in this manual.
8.2 After-sales Service
When the unit in warranty has a quality issue or fails to operate properly under the allowable operation 
condition, please contact the local sales representative for free service.
The user is required to designate personnel to take charge of the unit following the instructions covered 
in this  manual,  otherwise  any maintenance  cost  caused by  the  improper  operation will  be  at the  user’s 
expense.