Carrier 25VNA Service Manual page 15

FLASH CODE
OPERATION
(Amber LED)
Event
Event 59
Event 68
System Malfunction
Event
25VNA EVENT / FAULT (CONT.)
Heat or Cool
Mode
58 Both Outdoor Air Thermistor Issue
Outside Normal Operating Range
(e.g. improper load calculation, sys-
tem match issue, outside cooling
range etc)
Service Valve left closed (Liquid or
Vapor)
Undercharged System
Cool
Indoor Airflow too low or off
Restriction in Filter Drier plus Long
Line Application and filter drier on
Indoor Unit
Restriction due to debris
Restriction in Circuits or Tubing
Restriction in Filter Drier plus filter
Both
drier on Outdoor Unit
Both Expansion Orifice Restriction
Outside Normal Operating Range
(e.g. improper load calculation, sys-
tem match issue, outside heating
range etc)
Service Valve left closed (Liquid
Service Valve)
Outdoor Airflow too low or off
Heat
Undercharged System
Reversing Valve Bypass
Restriction due to debris
Loss of power while EXV is open
leading to charge migration to com-
pressor sump
EXV harness not connected to ODU
control
Both
EXV coil not connected to EXV
TXV failed open
Inverter PFC Thermistor sensor
failed open
Noisy Line Voltage
Short Circuit in system
69 Both
Compressor Winding Damage
Inverter Damaged
71 Cool Shorted sensor circuit
Possible Causes
See Error 53 and\or Error 56
Consult Application Guidelines
Ensure Service Valves are open
Check system subcooling to determine
charge status, if low add charge using
Charging Mode (follow proper charging
procedures)
Check Indoor for clogging (ice or debris)
and clean or de ---ice if necessary;
Troubleshoot Indoor fan motor and
make sure it is working; follow Indoor
Airflow troubleshooting instruction
Clean System (refer to application
guideline) and replace filter drier
Clean System (refer to application
guideline) and replace filter drier
Check kinks and straighten or replace
circuits
Clean System (refer to application
guideline) and replace filter drier
If short lineset (less than 15 ft)
Troubleshoot TXV (see guide below); re-
place if necessary
Troubleshoot EXV (see guide below)
Consult Application Guidelines
Ensure Liquid Service Valve is open
Check Outdoor for clogging (ice or
debris) and clean or de ---ice if neces-
sary; Troubleshoot Outdoor fan motor
and make sure it is working; follow Out-
door Airflow troubleshooting instruction
Check charge in cooling (if in Cooling
Charge Mode Ambient Range), if low
add charge using Charging Mode (follow
proper charging procedures); if out side
cooling charge mode range, pull out
charge, weigh in using heating charge
mode
Reversing Valve Stuck halfway;
troubleshoot reversing valve
Clean System (refer to application
guideline) and replace filter drier
Nothing; system is warming up com-
pressor sump temperature. Might take
up to 2 hours thus secondary heat might
be requested if necessary.
Check harness connection to ODU con-
trol
Check EXV coil and ensure it is well
seated
Check TXV operation and replace if ne-
cessary
Replace Inverter
Check line wiring and ensure proper
contacts (disconnects etc)
Check for system short circuit (loose
wire, damaged contacts etc)
Check compressor winding resistances;
See Compressor Troubleshooting
Check for system short circuit (loose
wire, damaged contacts etc); Replace
Inverter
Troubleshoot the compressor motor
thermistor. Compressor sensor fusite
should measure 5 kohm between motor
and common terminals.
15
ACTION