Failure Diagnosis - Lennox FLATAIR KFC Series Installation And Operating Manual

4.- MAINTENANCE

4.3.- FAILURE DIAGNOSIS

In case of failure or malfunction of the unit, the Display on the Control Panel will show an Error or Alarm warning
explained in the Control Panel Manual. Nevertheless, whenever there is a unit failure, the unit should be shut down
and our Service Technicians consulted.
FAILURE
UNIT DOES NOT START
UNIT STOPS DUE TO HIGH
PRESSURE DURING THE
COOLING CYCLE
UNIT STOPS DUE TO LOW
PRESSURE
UNIT STARTS AND STOPS IN
SHORT CYCLES
LOAD AND ABNORMAL
NOISE IN THE
COMPRESSOR (SCROLL)
WATER LEAKS
POSSIBLE CAUSES
Failure in the power supply, or
insufficient voltage.
Circuit breakers have opened.
Power cable or Control Panel cable
is defective.
High Pressure switch is defective.
Fan is not working.
Fan turns in the wrong direction.
Coil is dirty or clogged for passing
air
Excess charge of the Refrigerant.
Low pressure switch defective.
Lack of refrigerant. Leak.
Clogged Cooling Circuit.
Dirty filter drier.
Compressor overcharged.
Compressor cuts off due to Klixon.
Lack of Refrigerant.
Power supply phases inverted
(three-phase compressor).
Clogged drainage.
Loose drainage pipe connections.
Dirty and overflowing trays.
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POSSIBLE SOLUTIONS
Connect the power supply or check
the voltage.
Reset.
Inspect and Correct.
Check Cut-off Pressure or
change Pressure Switch if necessary.
Check for voltage, inspect the motor and
turbine or replace if necessary.
Switch the power phases.
Inspect and Clean.
Remove the charge and charge
according to the data on the Rating Plate.
Check the Cut-off Pressure with a
pressure gauge and change the
Pressure switch if necessary.
Correct leak, create vacuum and charge.
Inspect and Correct or Change the
Filter drier.
Inspect suction and discharge pressure
values and correct.
Inspect input voltage and voltage drop.
Correct leak and replace.
Inspect and switch power phases.
Inspect and Clean.
Correct connection.
Inspect and Clean.