Carrier 25VNA Service Manual page 16

FLASH CODE
OPERATION
(Amber LED)
Event
Event
Event
Event
System Malfunction
25VNA EVENT / FAULT (CONT.)
Heat or Cool
Mode
72 Cool High Suction Gas Temperature
Outdoor Airflow too low or off
75 Both
Blocked Inverter Heat Exchanger
(fins)
Application violates guideline
High Current Spikes in current
77 Both
measured by the Inverter drive
Inverter Output to Compressor
leads miswired leading to com-
pressor running backwards
Inverter Output to Compressor
leads not attached
Reversing Valve Bypass
79 Both
Compressor Winding damage
Overcharge, Attic run lineset and
High Load conditions
Outside Normal Operating Range
82 Cool
(e.g. improper load calculation, sys-
tem match issue, outside cooling
range etc)
Possible Causes
System will try to ride through current
spikes and self ---recover in trip condition;
persistent over current trips will lead to
Error 82 "Suction Over Temp Lockout"
(Refer to Error 82 troubleshooting)
Check ODU coil for clogging (ice or
debris) and clean if necessary;
Troubleshoot ODU fan motor and make
sure it is working
Check Inverter fins for debris and clean if
necessary
Consult Application Guideline for compli-
ance
System will try to ride through current
spikes and self ---recover in trip condition;
persistent over current trips will lead to
Error 95 "High Current Lockout" (Refer
to Error 95 troubleshooting)
check wiring at Inverter outputs
check wiring at Inverter outputs
Reversing Valve Stuck halfway;
troubleshoot reversing valve
Troubleshoot compressor windings. For
the 2 and 3T the resistance should be
.681 ohm and for 4 and 5T the resist-
ance should be .203 ohm at 70F
+/ ---20F. See compressor troubleshoot-
ing guidelines. If confirmed replace
compressor
Verify charge by putting in cooling char-
ging mode
Consult Application Guidelines
16
ACTION