Technical information

Portable Chillers UGH024/1103
6-22 TROUBLESHOOTING
Water-cooled chillers have a differential pressure switch
(PDS-1) on the condenser water. This switch indicates a high-
pressure drop through the condenser and strainer, usually the
result of a dirt strainer or fouled condenser. The alarm light
(and strobe) illuminate and the PLC displays the message
"Condenser Filter Fault". The compressor and pump(s) contin-
ue to run. Press the Enter button to clear the message from
the screen. The message continues to display every 60 min-
utes.
The 7.5 HP and larger compressors have a High Temperature
Protector Module to protect the compressor from high internal
temperatures, overcurrent conditions and phase imbalance. On
single compressor systems (and dual compressor systems with
only one compressor enabled), when the normally closed con-
tact opens, it shuts off the compressor immediately and the
contact remains open for 30 minutes. The PLC indicates
"Comp 1 Rotation Error" on single compressor systems and
for compressor 1 on dual compressor systems. A fault on com-
pressor 2 on a dual compressor system displays "Comp 2
Rotation Fault". When the contact closes and the fault is
acknowledged, the compressor will restart. On dual compres-
sor units, if the lead compressor's Protector Module contact
opens, the lag compressor becomes the lead compressor and
the alarm is displayed. When the 30-minute delay has expired
and the alarm is acknowledged, the compressor that had fault-
ed remains the lag compressor. If the lag compressor's
Protector Module contact opens, the compressor shuts off and
the alarm is initiated. This alarm can be cleared after the 30-
minute delay and the alarm is acknowledged.
To clear the alarm(s) press and hold the Shift button for three
seconds. To start the chiller once the 3-minute compressor
down time has expired, press the Run button on the Run
Screen.
The alarms are logged in an alarm history table. The last 5
alarms (except the high temp deviation alarm) are recorded
and display on the Alarm screen, along with the alarm num-
ber, To Process temperature set point, the actual To Process
temp, the Refrigerant Discharge Pressure, Refrigerant Suction
Pressure, and the time since the last alarm condition. An addi-
tional 2 alarm histories are displayed in the Conair Factory
screens.
PLC CONTROL
ALARM
CONDITIONS
CONT’D
Comp 1 Rotation Error
Comp 2 Rotation Error
Condenser Filter Fault