Advantage Engineering Maximum Instruction Manual page 26

MK Series Portable Chiller : Air-Cooled : HE INSTRUMENT
5. When the START key is pressed, the instrument will
immediately check the status of the motor overload switch
(PUMP OL light), the high pressure safety switch (HI
PRESSURE light), the low pressure safety switch (LOW
PRESSURE light), the low oil pressure safety switch (LOW
OIL light), and the freezestat safety switch (FREEZESTAT
light) for acceptable operating conditions. If these systems
are found to be 'ok', the lights will be 'solid green' and the
unit will begin process operations. If a system is not found
to be 'ok', the light will 'flash red' and the instrument will
prevent operation (check the troubleshooting section of this
manual for more information):
a. Motor overload switch open: a 'flashing red'
PUMP O/L light indicates the electric pump motor
overload relay is open. The pump motor is
protected from overload conditions (excessive flow)
by a set of thermal overload relays which open
(trip) with excessive amperage and prevent electric
power from reaching the electric motor. If the
overload relay is open, the overload relay must be
reset before operations can continue. An excessive
flow condition must be corrected immediately.
b. High pressure switch open: a 'flashing red' HI
PRESSURE light indicates the refrigerant high
pressure switch is open. This normally occurs when
condensing pressures exceed normal parameters.
To continue operations, the operator must reset the
safety switch by pressing in the reset lever. An high
pressure condition must be corrected immediately.
c. Low pressure switch open: a 'flashing red' LOW
PRESSURE light indicates the low pressure safety
switch is open. Chiller operations stop when the
refrigerant suction pressure drops below 58 PSI.
While the compressor is inactive, the pressure
normally builds back up to the cut-in pressure of 63
PSI, at which point the low pressure safety switch
automatically resets, and a 3 minute time delay
cycle begins (to prevent compressor short-cycling).
If the low pressure safety switch does not reset,
operations are prevented. Contact the service
department for further instructions.
d. Low oil pressure switch open: a 'flashing red'
LOW OIL light indicates the oil pressure safety
switch is open. The oil pressure safety switch is
found on 15 to 30 ton semi-hermetic compressors.
Normally, the switch will open if there is insufficient
oil in the compressor crankcase or due to lack of
sufficient compressor warn up before operations
ADVANTAGE ENGINEERING, INC.
525 East Stop 18 Road Greenwood, Indiana 46142
317-887-0729
Service Department Fax: 317-885-8683
Email: service@AdvantageEngineering.com
Fax: 317-881-1277
Page: 26