18-BB42D1-1A-EN
31
Troubleshooting Chart
PP--PPR
RIIM
MA
AR
RY
Y C
CA
AU
US
SEES
S // S
S--S
SEEC
CO
ON
ND
DA
AR
RY
Y C
CA
AU
US
SEES
S
SYSTEM FAULTS
Power
Supply
High
Voltage
Wiring
Compr.
I0L
Run
Capacitor
Start
capacitor
Start
Relay
Contactor
Contacts
Low
Voltage
Wiring
Control
Transformer
Contactor
Coil
Low
Voltage
Fuse
Stuck
Compressor
Ineffecient
Compressor
Refrigerant
Undercharge
Refrigerant
Overcharge
Excessive
Evap.
Load
Noncondensables
Restricted
O.D.
Airflow
O.D.
Air
Recirculation
TXV
Stuck
Open
Low
Superheat
High
Superheat
Restricted
I.D.
Airflow
Ref.
Circuit
Restrictions
REFRIGERANT CIRCUIT
Liquid Pressure too High
P
S
P
S
S
Liquid Pressure too Low
S
P
S
S
S
Suction Pressure too High
S
P
P
S
S
Suction Pressure too Low
S
S
P
S
Liquid Refrigerant
Floodback (TXV System)
S
S
P
I.D. Coil Frosting
P
S
P
S
Compressor Runs
Inadequate or No Cooling
S
P
P
S
S
S
S
P
S
ELECTRICAL
Compressor & O.D. Fan Do
Not Start
P
P
S
S
P
P
P
Compressor will not Start
but O.D. Fan Runs
P
S
P
P
P
S
O.D. Fan will Not Start
P
P
Compressor Hums but will
Not Start
P
P
P
P
S
S
Compressor Cycles on IOL
P
S
P
P
P
S
P
S
P
S
S
S
S
S
S
S
I.D. Blower willnot Start
P
S
S
P
P