Technical information

Page: 24
VL Series Portable Chillers, 2 to 40 Tons UGH021/0301
determines an indicating light or digit does not illuminate,
the instrument must be removed and sent to the factory for
repair. When power is supplied to the unit, the POWER
light will illuminated.
3. Toggle ‘on’ the CHILLER ON rocker switch to activate the
chiller. The operator can stop process operations
(refrigerant and coolant circuits) by switching ‘off’ the
CHILLER ON switch.
4. To select the operating setpoint, use the SELECT key to
index through the TO PROCESS and SET POINT
temperature functions until the SET POINT light is
illuminated.
5. When the SET POINT light is illuminated, the setpoint
temperature is shown in the temperature display window.
Use the UP and DOWN ARROW keys to change the
setpoint temperature.
6. PRECAUTIONS: the instrument is programmed from the
factory with a setpoint range of 48° to 70°F. To operate
below 48°F, the addition of inhibited propylene glycol and
modification of the safety control settings are required.
Diligent monitoring of the water/glycol solution is
mandatory to prevent freezing of the evaporator. Freezing
may cause the evaporator to rupture allowing water and
freon to mix which will cause major damage to the
refrigeration system. Operating above 70°F requires the
addition of a refrigerant crankcase pressure regulating (CPR)
valve. The CPR valve is necessary to prevent overloading of
the compressor which can cause premature failure. Contact
your local refrigeration contractor or the factory for further
information. The operating range of the instrument may be
changed to 20°F - 90°F by adjustment of the CPU DIP
switch. Refer to the technical section of this manual for
more information. The instrument is set up from the factory
to give an alarm light and a 115 volt alarm output if the
temperature to process deviates more than 10° from the
setpoint.
7. After selecting the setpoint temperature, the operator may
leave the display in the SET POINT state. The display will
automatically return to the TO PROCESS temperature state
after twenty seconds of inactivity.
8. The operator can stop operations by switching ‘off’ the
CHILLER ON rocker switch. This will disengage the
refrigerant and coolant circuits.