York HIDS006B21S Service Manual page 50

TROUBLESHOOTING
Alarm
Code
l The RUN indicator (red) flashes.
l The indoor unit number (refrigerant cycle number - address number), the alarm code, the model code
the model name
number and the alarm code are displayed on the 7-segment display of the outdoor unit PCB.
Note 1: Except for some models.
This alarm code is displayed when a short (0.24kΩ or less) or open sensor (840kΩ or more) is detected
during a heating or cooling operation. The operation automatically restarts when the malfunction is
removed.
Is thermistor THM3
(for freeze protection)
connected to THM3 of
I.U. PCB?
Yes
Is resistance of THM3
between 0.24kΩ and
840kΩ?
Yes
Failure of I.U. PCB
Medium Static Type: (H,Y,C)IDM006 to 048B21S
Event
Failure of
Freeze Protection
Thermistor
Failure of I.U. PCB
3-28
Abnormality of Thermistor for Liquid Refrigerant Pipe Temperature
at Indoor Unit Heat Exchanger (Freeze Protection Thermistor)
1
and the number of connected indoor units are displayed on the LCD. The indoor unit
No
Connect them.
No
Failure of
Thermistor
Refer to "Alarm Code 11"
for thermistor resistance.
Thermistor for Indoor Heat
Exchanger Liquid Pipe
Temperature
(For Freeze Protection)
Cause
Failure
Incorrect Connection
High Static Type: (H,Y)IDH018 to 048B21S
Thermistor for Indoor Heat
Exchanger Liquid Pipe
Temperature
(For Freeze Protection)
Slim Type: (H,Y,C)IDS006 to 018B21S
Check Item
Check resistance.
Check wiring to
I.U. PCB.
Replace I.U. PCB
and check operation.
1
,
Thermistor for Indoor Heat
Exchanger Liquid Pipe
Temperature
(For Freeze Protection)
Action
(Turn OFF Main Switch)
Replace thermistor
if faulty.
Correctly connect wires.
Replace I.U. PCB
if faulty.
SM-18001-rev.1