Performance Troubleshooting - Carrier 50YFV Installation, Operation And Maintenance Instructions

R e s i d e n t i a l D i g i t a l P a c k a g e d U n i t s G T- P B S e r i e s - 6 0 H z P u r o n
Fault
Unit Performance
Sentinel-Code 8
Swapped Thermistor
Code 9
ECM Fault - Code 10
Low Air Coil Pressure Fault
Low Air Coil Pressure Fault
(ClimaDry) Code 11
(Whole House
Dehumidifi cation) Code 11
Low Air Coil Temperature
Low Air Coil Temperature
Fault - (ClimaDry) Code 12
Fault - (Whole House
Dehumidifi cation) Code 12
IFC Fault Code 13
Internal Flow
Controller Fault
ESD - ERV Fault (DXM Only)
Green Status LED Code 3
No Fault Code Shown
Unit Short Cycles
Only Fan Runs
Htg C lg Possible Cause
X Heating Mode LT2>125°F
Cooling Mode LT1>125°F OR
X
LT2< 40°F
X X LT1 and LT2 swapped
X X Blower does not operate
Blower operating with incorrect
airflow

Performance Troubleshooting

X Reduced or no air flow in cooling
or ClimaDry
Whole House Dehumidifi cation
Air temperature out of range
Bad pressure switch
X Reduced airflow in cooling,
Whole House Dehumidifi cation, or
ClimaDry, or constant fan
constant fan
Air temperature out of range
Bad thermistor
No pump output signal
X X
Low pump voltage
No pump feedback signal
Bad pump RPM sensor
ERV unit has fault
X X
(Rooftop units only)
X X No compressor operation
X X Compressor overload
X X Control board
X X Dirty air filter
X X Unit in 'Test Mode'
X X Unit selection
X X Compressor overload
X X Thermostat position
X X Unit locked out
X X Compressor overload
X X Thermostat wiring
Functional Troubleshooting (cont.)
Solution
Check for poor air flow or overcharged unit
Check for poor water flow, or air flow
Reverse position of thermistors
Check blower line voltage
Check blower low voltage wiring
Wrong unit size selection
Wrong unit family selection
Wrong motor size
Incorrect blower selection
Check for dirty air filter and clean or replace
Check fan motor operation and airflow restrictions
Too high of external static - check static vs blower table
Too much cold vent air - bring entering air temp within
design parameters
Check switch continuity and operation - replace
Check for dirty air filter and clean or replace
Check fan motor operation and airflow restrictions
Too high of external static - check static vs blower table
Too much cold vent air - bring entering air temp within
design parameters
Check temp and impedance correlation per chart
Check DC voltage between A02 and GND - should be
between 0.5 and 10 VDC with pump active
Check line voltage to the pump
Check DC voltage between T1 and GND. Voltage should
be between 3 and 4 VDC with pump OFF, and between
0 and 2 VDC with the pump ON
Replace pump if the line voltage and control signals are
present at the pump, and the pump does not operate
Troubleshoot ERV unit fault
See 'Only Fan Operates'
Check and replace if necessary
Reset power and check operation
Check and clean air filte r
Reset power or wait 20 minutes for auto exit
Unit may be oversized for space - check sizing for actual
load of space
Check and replace if necessary
Insure thermostat set for heating or cooling operation
Check for lockout codes - reset power
Check compressor overload - replace if necessary
Check thermostat wiring at DXM2 - put in Test Mode and
jumper Y1 and R to give call for compressor
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