Rheem A180CL25E, Installation Instructions Manual

Page: 27 / 37

27
WARNING !
FIGURE 24
COOLING TROUBLE SHOOTING CHART
DISCONNECT ALL POWER TO UNIT BEFORE SERVICING. CONTACTOR MAY BREAK ONLY ONE SIDE. FAILURE
TO SHUT OFF POWER CAN CAUSE ELECTRICAL SHOCK RESULTING IN PERSONAL INJURY OR DEATH.
SYMPTOM POSSIBLE CAUSE REMEDY
Unit will not run • Power off or loose electrical connection • Check for correct voltage at compressor contactor in control
box
• Thermostat out of calibration-set too high • Reset
• Failed contactor • Check for 24 volts at contactor coil - replace if contacts are
open
• Blown fuses • Replace fuses
• Transformer defective • Check wiring-replace transformer
• High pressure control open (if provided) • Reset-also see high head pressure remedy-The high pressure
control opens at 450 PSIG
• Interconnecting low voltage wiring damaged • Replace thermostat wiring
Condenser fan runs, compressor • Loose connection • Check for correct voltage at compressor -
doesn’t check & tighten all connections
• Compressor stuck, grounded or open motor winding • Wait at least 2 hours for overload to reset.
open internal overload. If still open, replace the compressor.
• Low voltage condition At compressor terminals, voltage must be within 10% of rating
plate volts when unit is operating.
• Low voltage condition • Add start kit components
Insufficient cooling • Improperly sized unit • Recalculate load
• Improper airflow • Check - should be approximately 400 CFM per ton.
• Incorrect refrigerant charge • Charge per procedure attached to unit service panel.
• Air, non-condensibles or moisture in system • Recover refrigerant, evacuate & recharge, add filter drier
• Incorrect voltage • At compressor terminals, voltage must be within 10% of rating
plate volts when unit is operating.
Compressor short cycles • Incorrect voltage • At compressor terminals, voltage must be ± 10% of
nameplate marking when unit is operating.
• Defective overload protector • Replace - check for correct voltage
• Refrigerant undercharge • Add refrigerant
Registers sweat • Low evaporator airflow • Increase speed of blower or reduce restriction - replace air
filter
High head pressure- • Restriction in liquid line, expansion device or filter drier • Remove or replace defective component
low vapor pressures • Flow check piston size too small • Change to correct size piston
• Incorrect capillary tubes • Change coil assembly
• TXV does not open • Replace TXV
High head pressure-high or • Dirty condenser coil • Clean coil
normal vapor pressure - • Refrigerant overcharge • Correct system charge
Cooling mode • Condenser fan not running • Repair or replace
• Air or non-condensibles in system • Recover refrigerant, evacuate & recharge
Low head pressure-high vapor • Defective Compressor valves • Replace compressor
pressures • Incorrect capillary tubes • Replace coil assembly
Low vapor pressure - • Low evaporator airflow • Increase speed of blower or reduce restriction - replace air
cool compressor - filter
iced evaporator coil • Operating below 65°F outdoors • Add Low Ambient Kit
• Moisture in system • Recover refrigerant - evacuate & recharge - add filter drier
High vapor pressure • Excessive load • Recheck load calculation
• Defective compressor • Replace
Fluctuating head & vapor • TXV hunting • Check TXV bulb clamp - check air distribution on coil - replace
pressures TXV
• Air or non-condensibles in system • Recover refrigerant, evacuate & recharge
Gurgle or pulsing noise at • Air or non-condensibles in system • Recover refrigerant, evacuate & recharge
expansion device or liquid line