Friedrich 2001 Hazardgard SH14J30A-1, Service Manual

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11
PROBLEM POSSIBLE CAUSE TO CORRECT
Unit does not
run.
PROBLEM POSSIBLE CAUSE TO CORRECT
Dirty Filter.
Restricted air flow.
Inoperative thermostat.
Short of refrigerant.
Partially restricted capillary.
Inoperative fan motor.
Heat sink triac shorted.
Evaporator
coil freezes
up.
PROBLEM POSSIBLE CAUSE TO CORRECT
Test cooling performance of unit. Unit undersized.
Check for partially iced coil. Check temperature split across
coil.
Check for presence of oil on silver soldered connections.
Check for partially iced coil. Check split across coil. Check
for low running amperage.
Check operation of thermostat. Replace if contacts remain
closed.
Replace both heat sink assembly and printed circuit control.
Compressor
runs
continually.
Does not
cycle off.
PROBLEM POSSIBLE CAUSE TO CORRECT
Place jumper across thermostat terminals. If unit operates,
replace thermostat.
Check as above.
Connect per wiring diagram.
Test for continuity at switch terminals 5 and 6.
Loss of charge in thermostat bulb.
Loose or broken parts in
thermostat.
Incorrect wiring.
System switch open.
Thermostat
does not turn
unit on.
Excessive heat load.
Restriction in line.
Refrigerant leak.
Thermostat contacts stuck.
Heat sink triac shorted.
PROBLEM POSSIBLE CAUSE TO CORRECT
Turn to highest temperature setting to see of unit will cycle off.
Disconnect power to the unit. Remove cover of thermostat
and check if contact is stuck, if so replace thermostat.
Test switch for open contacts at terminals 5 and 6, 2 and 3
with switch in “Off” position. Thermostat set at coldest point
Thermostat contacts stuck.
Switch (On - Off) shorted.
Thermostat
does not
turn unit off.
Power disconnected.
System switch in “Off” position.
Branch circuit fuse blown or
circuit breaker tripped.
Inoperative system switch.
Loose or disconnected wiring at
switch.
Inoperative switch (On-Off).
Clean as recommended in Owner’s Manual.
Check for dirty or obstructed coil - clean as required.
Test for shorted thermostat or stuck contacts.
De-ice coil and check for leak.
De-ice coil. Check temperature differential across coil. Touch
test coil return bends for same temperature. Test for low
running current.
Test and replace if inoperative.
If thermostat is functioning properly and compressor cycles,
replace both heat sink and printed circuit board.
Check power source.
Set switch correctly.
Replace fuse, reset breaker. If repeats, check fuse or breaker
size. Check for shorts in unit wiring and components.
Test for continuity.
Check wiring and connections. Connect per wiring diagram.
Test for continuity, 3 and 2, 5 and 6.
TROUBLESHOOTING