Operating Manual - John Morris Scientific

WARNING
CODE 21
WARNING
CODE 22
WARNING
CODE 23
WARNING
CODE 24
WARNING
CODE 25
ALARM
CODE 33
Internal safetytemperature
sensor
short-circuited or
interrupted.
Ultra-Low Refrigerated Circulators
Compressor stage 1 does not work.
After a short cooling interval, the compressor motor will be
automatically reconnected and the message "CODE 21" no longer
appears.
Compressor stage 2 does not work.
Cooling compressor overload protection
The motor of the cooling compressor is equipped with an overload
protector, which will be activated by excessive temperature in the
capsule or by excessive current consumption.
Causes for motor disconnection:
- poor air circulation
- small distance to walls
- dirt accumulated on condenser
- high ambient temperature
- switch-off and on for short intervals
Excess temperature in stage 1 of the compressor.
Excess temperature in stage 2 of the compressor.
Short-circuit in the control cable for the refrigerating machine during
self-test.
Cable of the excess temperature sensor interrupted or short-circuited.
ALARM
CODE 38
Ext. Sensor input
without signal but
setpoint programming
set to ext. Pt100.
Ext. Pt100 sensor input without signal, but setpoint programming set
to external Pt100.
WARNING
CODE 40
The early warning system for low level signals a critical fluid level.
Replenish the bath tank with the bath fluid.
After eliminating the malfunction, press the mains power switch off and
on again to cancel the alarm state.
If the unit cannot be returned to operation, contact an authorized
JULABO service station.
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