Rheem RP18AZ60AJVCA User Manual

38
WARNING: 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
• Thermostat set too high or low.
• Unit in active compressor protection
• lockout mode
• Blown fuses/tripped breaker
• Transformer defective
• High-pressure control lock-out
• Low-pressure control lock-out
• Miswiring of communications (communication
light on continuously)
• Defective control board
• Check for correct voltage at line voltage connections in
condensing unit.
• Reset – Power cycle high and low voltage to outdoor
• unit.
• Check control board diagnostic codes.
• Replace fuses/reset breaker.
• Check wiring. Replace transformer.
• Reset by cycling power to unit. Also see high head
pressure and low suction pressure remedies.
• Check for refrigerant leaks.
• Check communication wiring.
Outdoor fan runs,
compressor doesn't
• Loose connection
• Communication cable disconnected or failed
• Compressor stuck, grounded or open motor
winding, open internal overload.
• Low-voltage condition
• Check for correct voltage at lter and inverter. Check
and tighten all connections.
• Check control board diagnostic codes.
• Replace
Insufcient cooling • Improperly sized unit
• Improper indoor airow
• Incorrect refrigerant charge
• Air, noncondensibles, or moisture in system
• Restricted Refrigerant Circuit
• Recalculate load.
• Check airow. Should be approximately 400 CFM [189
l/s] per ton.
• Charge per procedure attached to unit service panel.
• Recover refrigerant. Evacuate and recharge.
Replace lter drier.
• Locate restriction and clear
Compressor short
cycles
• Incorrect voltage
• Improperly sized unit
• Refrigerant undercharge or overcharge
• (LPC or HPC Cycling)
• At inverter input terminals, voltage must be between
187-252 VAC when unit is operating.
• Adjust charge per charging chart.
Registers sweat • Low indoor airow • Increase speed of blower or reduce restriction.
Replace air lter.
High head, low vapor
pressures
• Restriction in liquid line, expansion device, or
lter drier
• Stuck EXV
• Remove or replace defective component.
• Verify EXV operation.
High head, high
or normal vapor
pressure – Cooling
mode
• Dirty outdoor coil
• Refrigerant overcharge
• Outdoor fan not running
• Air or noncondensibles in system
• Clean coil.
• Correct system charge.
• Repair or replace.
• Recover refrigerant. Evacuate and recharge.
Low head, high vapor
pressures
• EXV in bypass mode
• Reversing Valve leaking by
• Bad compressor
• Verify thermostat connections at EXV control
• Verify thermistor and pressure transducer connection
and operation
• Replace reversing valve
• Replace compressor.
Low vapor, cool
compressor, iced
indoor coil
• Low indoor airow
• Operating below 55°F outdoors
• Moisture in system
• Low ambient cooling not operating (coil or
ambient thermistor failure)
• Increase speed of blower or reduce restriction.
Replace air lter.
• Recover refrigerant. Evacuate and recharge. Replace
lter drier.
High vapor pressure • Excessive load
• Defective compressor
• Recheck load calculation.
• Replace compressor.
Fluctuating head and
vapor pressures
• EXV hunting
• Air or noncondensibles in system
• Check thermistor to vapor line connection. Check air
distribution on coil.
• Check suction thermistor and pressure transducer
operation
• Recover refrigerant. Evacuate and recharge.
• Remove & conrm EXV movement. Clean EXV inside
with nitrogen to remove any debris then reinstall
Gurgle or pulsing
noise at expansion
device or liquid line
• Air or noncondensibles in system
• Undercharge long line application
• Recover refrigerant. Evacuate and recharge.
• Adjust charge per charging chart.
9.2 General Troubleshooting Guide
Table 17: Troubleshooting Guide
Diagnostics

Rheem RP18AZ60AJVCA Specifications

General

Brand	Rheem
Model	RP18AZ60AJVCA
Category	Air Conditioner
Language	English