S
HUT
D
OWN
A
LARMS
UGH004/0999
microKool Portable Chillers
T
ROUBLESHOOTING
6-9
Alarm
Refrigerant pressure
is either too low or
too high.
Process fluid in the
chiller tank is at the
minimum level.
The Freeze Stat
Input is open.
Possible cause
High refrigerant pressure
Is the temperature of the
condenser supply air or
water too high?
Is the refrigerant over-
charged?
Is there enough fluid in
the tank?
Is there sufficient fluid
flow through he evapora-
tor?
Is the freezestat setting
too high?
Is the freezestat sensor
installed correctly?
Solution
Load conditions may be too
high for proper operation.
Air-cooled chillers will not
work properly if the ambient
air temperature is above
100° F (38° C).
Water-cooled chillers will not
work properly if the condenser
water supply temperature is
above 85° F (29° C). Check
cooling tower operation, if a
tower supplies the water.
Contact a certified refrigerant
technician for servicing.
Check the fluid level by look-
ing at the tank level sight glass
at the rear of the chiller. Add
fluid, if necessary. See
F
ILLING
THE
T
ANK
.
Check for incorrect pump rota-
tion and closed valves in the
process circuit. Verify required
GPM rating for the chiller:
(GPM=2.4 x chiller ton capacity)
Setting should be 10° F (5° C)
below the operating tempera-
ture, and at least 5° F (2° C)
above the freezing point of the
process fluid.
Check that the sensor bulb is
well insulated and inserted
completely into piping well.
Low Water Alarm
Refrigerant Pressure
The chiller has detected a problem that could lead to equipment
damage or personal injury if it is not corrected.
◆
The Alarm LED lights and the STOP/RUN LED flashes red.
◆
The chiller turns off the compressor, but normal operation
resumes after you clear the alarm or the problem corrects itself.
◆
The control displays a red LED or alarm code indicating the
source of the problem.
Freeze Stat Alarm
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