Friedrich HazardGard 60 Hz Service & Parts Manual page 9

PROBLEM
COMPRESSOR
ATTEMPTS TO
START, OR RUNS
FOR SHORT
PERIODS ONLY.
CYCLES ON
OVERLOAD.
COMPRESSOR DOES
NOT START - FAN
MOTOR RUNS.
DOES NOT COOL,
OR COOLS ONLY
SLIGHTLY.
TROUBLESHOOTING (Continued)
POSSIBLE CAUSE
Compressor attempts to start
before system pressures are
equalized.
Low or fl uctuating voltage.
Incorrect wiring.
Shorted or incorrect capacitor.
Restricted or low air fl ow through
condenser coil.
Compressor running abnormally
hot.
Overload opens too soon.
Thermostat contacts not closing.
Low voltage supply.
Switch (On-Off) inoperative.
Open capacitor.
Internal overload open.
Relay open
Open or shorted compressor
windings
Thermostat open or inoperative.
Dirty air fi lter.
Dirty or plugged condenser or
evaporator coil.
Poor air circulation in area being
cooled.
Low capacity - undercharge.
Compressor not pumping properly.
TO CORRECT
Allow a minimum of two (2) minutes to allow pressures to
equalize before attempting to start.
Check voltage with unit operating. Check for other
appliances on the circuit. Unit should be on separate circuit
for proper voltage, and be fused separately.
Connect per wiring diagram.
Check by substituting a known good capacitor of correct
rating.
Check for proper fan speed or blocked condenser.
Check for kinked discharge line or restricted condenser.
Check amperage.
Change compressor if all other corrections above are
normal.
Check continuity of thermostat at coldest setting. Jump
contacts, if compressor runs, replace thermostat.
Check for nameplate voltage.
Test for continuity.
Check by substituting a known good capacitor of correct
rating.
Check voltage at compressor terminals. If voltage is
satisfactory, replace compressor.
Replace relay
Check windings for continuity and resistance. Direct test
compressor. If direct test fails, replace compressor.
Set to coldest position. Test thermostat and replace if
necessary.
Clean as recommended in Owner's Manual.
Use steam or detergents to clean.
Adjust air louvers.
Clean, check for leak and make repair.
Check amperage draw against nameplate. If not conclusive,
make pressure test.
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