Goodman Mfg IO - 395 - Manual (Page 14)

14
TROUBLESHOOTING CHART
SYMPTOM
High head - low suction a. Restriction in liquid line or flowrator a. Remove or replace with proper size flowrator.
High head - high or normal suction a. Dirty condenser coil a. Clean coil.
b. Overcharged b. Correct System charge.
c. Condenser fan not running c. Repair or Replace.
a. Incorrect flowrator a. Replace with correct flowrator.
b. Defective compressor valves b. Replace compressor.
c. Flowrator not seating properly c. Check for debris under flowrator or deformed
flowrator. Remove debris or replace flowrator.
d. Defective reversing valve d. Replace reversing valve.
a. Power off or loose electrical connection a. Check for unit voltage at contactor in unit.
b. Thermostat out of calibration set too high b. Reset.
c. Defective contactor
c. Check for 24 volts at contactor coil replace if
contacts are open.
d. Blown fuses or tripped breaker d. Replace fuse or reset breaker.
e. Transformer defective e. Check wiring - replace transformer.
f. High or low pressure control open
(Optional)
f. Reset high pressure control or check unit charge.
High pressure control opens at 610 psig.
Low pressure control opens at 22 psig.
g. Compressor overload contacts open g. Replace compressor.
NOTE: Wait at least 2 hours for overload to reset.
Condenser fan runs,
compressor doesn't a. Loose connection a. Check for unit voltage at compressor check &
tighten all connections.
b. Compressor stuck, grounded or open
winding open internal overload
b. Wait at least 2 hours for overload to reset If still
open, replace the compressor.
c. Low voltage connection c. At compressor terminals, voltage must be within
10 % of nameplate volts when unit is operating.
d. Capacitor weak, open, or shorted d. Check capacitor. If defective, replace.
Low suction - cool compressor a. a.
Iced evaporator coil
a. Defective overload protector a. Replace - check for correct voltage.
b. Unit cycling on low pressure control b. Check refrigerant charge and / or airflow.
a. a. Increase speed of blower or reduce restriction
replace air filters.
a. Excessive load a. Recheck load calculation.
b. Defective compressor b. Replace.
c. Reversing valve not seating properly. c. Replace.
a. Improperly sized unit a. Recalculate load.
b. Improper airflow b. Check - should be approximately 400 CFM per
ton.
c. Incorrect refrigerant charge. c. Charge per procedure attached to unit service
panel.
d. Incorrect voltage d. At compressor terminals, voltage must be within
10% of nameplate volts when unit is operating.
Increase speed of blower or reduce restriction -
replace air filters.
Insufficient cooling
High suction pressure
REMEDY POSSIBLE CAUSE
Compressor short cycles
Registers sweat Low airflow
Low head - high suction
Unit will not run
Low indoor airflow