50
Troubleshooting
Phase Protector
The unit with Scroll Compressor can only rotate in one direction. For this reason, a protective device (phase
protector) is fitted to prevent incorrect wiring of the electrical phases. When the three phases are not connect-
ed correctly, the phase protector operates, and the unit will not start.
This device is located in the control box of the outdoor unit.
The following table shows the LED indicator light for phase protector under normal operation and fault
conditions.
Model: UATN60/90C
LED
Description
PW
(Red)
P_S
(Yellow)
P_T
(Yellow)
Actions
Normal Operation
-
Reverse Phase
Switch off
the unit. Check the 3 phase wiring.
T Phase Missing
Switch off
the unit. Check the 3 phase wiring.
S Phase Missing
Switch off
the unit. Check the 3 phase wiring.
R Phase Missing
Switch off
the unit. Check the 3 phase wiring.
Overheat
High discharge temperature. Check the refrigerant
system.
Sensor missing
Switch off
the unit. Plug in sensor.
ON
OFF
Fast Blink
Model: UATN120/150/180/210/240/300C
Notes: 1. “+” indicates additional functions for PP01 phase protector.
2. When R phase missing, no LED or buzzer will indicate the error, but relay 71 and relay 81 will cut off.
LED
Description
PW
(Red)
P_R
(Yellow)
P_S
(Yellow)
P_T
(Yellow)
Actions
Normal operation
-
Reverse phase
Switch off the unit. Check the 3 phase wiring.
T phase missing
Switch off the unit. Check the 3 phase wiring.
S phase missing
Switch off the unit. Check the 3 phase wiring.
R phase missing
Switch off the unit. Check the 3 phase wiring.
S &T phase missing
+
Switch off the unit. Check the 3 phase wiring.
Overload
+
High discharge temperature. Check the refrigerant system.
Sensor missing
+
Switch off the unit. Plug in sensor.
ON
OFF
Fast Blink
WARNING
Troubleshooting must be performed by qualified personnel.
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Summary of Contents for UATN120CGXY1
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Page 4: ...Table of Contents ii...
Page 48: ...44 Wiring Diagrams Wiring Diagrams Model UATN60 90C...
Page 49: ...45 Wiring Diagrams Model UATN120 150 180C...
Page 50: ...46 Wiring Diagrams Model UATN210 240 300C...
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