Carrier 25VNA - Page 14

14
25VNA EVENT / FAULT (CONT.)
OPERATION
FLASH CODE
(Amber LED)
Heat or Cool
Mode
Possible Causes ACTION
Event 49 Both
Contactor dropping out momentar-
ily
Verify contactor harness from ODU con-
trol (”C C” harness); check f or loose con-
nection, stripped wires, short to ground
or short between wires; confirm good
connection is made at control board and
at contactor
Voltage glitches and low line
voltages
if persistent contact power provider
Damaged Inverter Drive
Change out ODU control before Inverter
Drive; if this does not help then change
out the Inverter drive
Fault 53 Both
Sensor Harness not connected to
ODU control
Ensure plug is connected to ODU con-
trol
Broken or loose harness wire
Check harness for continuity; resistance
should measure 10 k at 77 +/--- 20
o
F.
Refertothermistor10kthermistorcurve.
If bad, replace OAT/OCT thermistor
sensor assembly
Broken or Da maged Sensor
Check harness for continuity; resistance
should measure 10 k at 77 +/--- 20
o
F.
Refertothermistor10kthermistorcurve.
If bad, replace OAT/OCT thermistor
sensor assembly
Hardware damage to ODU control Replace ODU control
Fault 54 Both
Sensor Harness not connected to
ODU control
Ensure plug is connected to ODU con-
trol
Broken or loose harness wire
Check harness for continuity; resistance
should measure 10 k at 77 +/--- 20
o
F.
Refertothermistor10kthermistorcurve.
If bad, replace OST sensor
Suction Thermistor not properly at-
tached or in wrong location
Ensure Sensor is properly attached to
the accumulator entry---tube
Broken or Da maged Sensor
Check harness for continuity; resistance
should measure 10 k at 77 +/--- 20
o
F.
Refertothermistor10kthermistorcurve.
If bad, replace OST sensor
Hardware damage to ODU control Replace ODU control
Fault 55 Both
Sensor Harness not connected to
ODU control
Ensure plug is connected to ODU con-
trol
Broken or loose harness wire
Check harness for continuity; resistance
should measure 10 k at 77 +/--- 20
o
F.
Refertothermistor10kthermistorcurve.
If bad, replace OAT/OCT thermistor
sensor assembly
Coil Thermistor not properly at-
tached or in wrong location
Ensure Sensor is properly clipped to the
distributor entry---tube
Broken or Da maged Sensor
Check harness for continuity; resistance
should measure 10 k at 77 +/--- 20
o
F.
Refertothermistor10kthermistorcurve.
If bad, replace OAT/OCT thermistor
sensor assembly
Hardware damage to ODU control Replace ODU control
Event 56 Both
Coil Thermistor not properly at-
tached or in wrong location
Ensure Sensor is properly clipped to the
distributor entry---tube
Outdoor Ambien t Temperature
sensor improperly installed (sensor
body may be in contact with sheet
metal)
Properly install OAT sensor
Fault 57 Both
Sensor Harness not connected to
ODU control
Ensure plug is connected to ODU con-
trol
Broken or loose harness wire
Check har ness for stripped wires, shot to
ground or short between wires.
Electrical short destroyed Trans-
ducer electronics
Compare transducer voltage reading to
gauge reading at service valve (see
Transducer Output Function graph);
Check system for electrical shorts and
correct; replace transducer.
Heat damage during brazing
Compare transducer reading to gauge
reading at service valve (see transducer
measurement chart); replace transdu cer
Event 58 Both
Suction Thermistor not properly at-
tached or in wrong location
Ensure plug is properly attached to suc-
tion tube
Broken or loose harness wire
Check harness for continuity; resistance
should measure 10 k at 77 +/--- 20
o
F.
Refertothermistor10kthermistorcurve.
If bad, replace OST thermistor sensor
assembly