Daikin GYEQ20AN Service Manual page 146

Flow Charts for Troubleshooting
5
Abnormal Cooling Water Temperature
Sub-code 0: While the unit is running, the cooling water temperature rises beyond 105°C.
Description
Sub-code 1: The cooling water temperature fails to reach 40°C within 20 minutes after the engine has started
of the failure
Cooling water pump failure; fan motor failure; water motor-operated valve failure; cooling water level too low;
Possible
causes cooling water filter clogged; radiator clogged; radiator cap faulty; thermostat failure; air extractor failure;
of the failure
short circuit; cooling water temperature sensor failure; main circuit board failure; cooling water leak
Flow chart
Is Radiator
Free From Clogging?
YES
Is Unit Free From
Short Circuits?
YES
Is Unit Free From
Cooling Water Leaks?
YES
Is Reservoir Tank Filled
With Cooling Water?
YES
Is Cooling Water Pump
Operating Normally?
YES
Is Fan Motor
Operating Normally?
YES
Is the cooling water
temperature sensor
operating normally?
YES
Is Cooling Water Temperature
Operating Normally?
YES
Is Cooling Water Temperature
Sensor Operating Normally?
YES
Replace thermostat components.
Replace water motor valve.
135
up.
NO
Check Clogging.
NO
Check Short-circuit.
NO
Check Cooling W
NO
Check Cooling Water Level.
NO
Check Cooling Water Pump.
NO
Check Fan Motor.
NO
Check Radiator Cap.
NO
Check Cooling Water
NO
Check Cooling Water
Temperature Sensor.
ater System.
Temperature.
025868-00EN02
SiAUY361411EA
Error
E4
code
Troubleshooting