Symptom
Cooling
Who can take
corrective action
U = User
S = specialised
personnel
Probable cause
Possible remedy
E The
compressor
does not start
because the
minimum
pressure switch
has tripped
x
s
Pressure switch out of order
Check and replace.
x
s
Machine completely void of
refrigerant
See point G.
u
Finned coil clogged, airflow rate
is too low
Remove dirt from the coil.
x
u
Water circulation pump blocked
Unlock the pump
x
s
Water circulation pump blocked
and defective
Check the pump and replace if
necessary
s
Presence of frost on the
evaporator coil
See point N.
s
Evaporator fan not working
See point F.
x
s
Refrigerant filter clogged
Check and replace.
x
s
Expansion device that is not
working properly
Check and replace if necessary.
x
s
Presence of moisture in the
refrigerant circuit
Replace the filter, dry and recharge
F The fans do
not start
x
s
Fan contactor de-energized
Check the voltage across the coil of
the contactor and the continuity of
the coil.
x
s
Lack of output voltage from the
control fan speed
Check the contacts, replace if
necessary.
x
s
Thermal protection inside the
fan
Check the condition of the fan and
the air temperature during operation
of the unit.
x
s
Fan motor faulty
Check and replace.
x
s
Loose electrical connections
Check and replace.
G Lack of gas
x
s
Loss in the refrigerant circuit
Check the cooling circuit using a leak
detector after pressurising the circuit
to approximately 4 bars.
Repair, evacuate and refill.
H Frost in the
liquid line
downstream
from a filter
x
s
The filter is clogged
Replace the filter
I The unit
works
continuously
without ever
stopping
x
s
Lack of refrigerant gas
See item G.
x
u
Incorrect tuning of the operating
thermostat
Check and set.
x
s
Excessive thermal load
Reduce the thermal load
x
s
Compressor does not give the
thermal output
Check, change or revise
x
s
The liquid filter is clogged
Replace.
L The unit
works regularly
but with an
insufficient
capacity
x
s
Low refrigerant charge
See point G.
