JULABO LH 85 High Dynamic Temperature System - Manual (Page 62)

Troubleshooting guide / Error messages
62
WARNING
CODE 45
The compressors of both stages are switched off due to wrong operation.
The temperature control system LH85 was switched too often by the
operating personnel with the key Start/Stop . The allowed switching
frequency of the compressors (5 times per hour). is exceeded. Until the end
of the hour the WARNING CODE 45 is shown.
Attention:
If the last key command was a „Start“, the compressors are switched on
again delayed after this hour. If this is not required, switch off and on again
the unit at the mains switch..
ALARM
CODE 46 The compressor of stage 2 was switched off again
After the delayed switching on of the compressor of stage 2, the pressure
(low pressure side) has fallen below a determined value after a period of 10
minutes. In order to avoid the destruction of the compressor, the refrigerant
cycle of stage 2 should be checked by a specialist.
ALARM
CODE 47
The cooling system is surcharged, and the compressor of stage 2 was
switched off.
Before the WARNING CODE 42 is shown for more than two hours. In order
to avoid the destruction of the compressor, the refrigerant cycle of stage 2
should be checked by a specialist.
ALARM
CODE 48 Caused by WARNING CODE 43 the compressor of stage 2 has switched
off 5 times within one hour.
If after a certain time there was a pressure compensation, the alarm status
can be cancelled by switching off and on at the mains switch, and the unit is
ready to operate again.
In order to avoid the destruction of the compressor, the refrigerant circuit
should first be checked by a specialist.
ALARM
CODE 49
The pressure sensor of stage 2 (evaporation pressure, low pressure side) is
bypassed or has a line interruption.
Have the repair done by a specialist.
ALARM
CODE 50 The pressure sensor of stage 2 (high pressure side) is bypassed or has a
line interruption.
Have the repair done by a specialist.
 Press enter
to quit the audible signal .
 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.