Operating Instructions WBL-118 Refrigerated bath and circulator
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Chapter 4 Maintenance
4.1 Regular maintenance
1) Clean the bath interior and exterior of the equipment periodically to keep the equipment
clean;
2) Check for hydraulic tightness and fastening of the connections for flexible hoses, fittings and
couplings;
3) Check fixing screws periodically, and if any loose, fix it.
Remove the plug from power line before cleaning. Use soft dry tissue to clean the bath
interior and avoid any splashing or washing!
If any water or other materials fall into the equipment containing electric and/or
electronic parts and components, disconnect the power immediately. Power on only
after water is completely evaporated or removed.
4.2 Regular check of the STB
Regular check of the STB is required for safe operation. Intervals of six months for normal use, or the
first time powering up after repairing or standstill for long period, are recommended for regular
check of the functionality. Check the STB as follows:
1) Set the temperature at 10°C above the ambient and/or the liquid, so that it keeps heating,
LED is continuously on;
2) Initiate the temperature control as for normal use, i.e. the pump is circulating and heating is in
full capacity;
3) Drain the bath so that the heater and the STB are exposed to the air completely. Make sure no
liquid spraying out from the circulating return, dripping from the drain device on the bench or
floor;
4) The liquid evaporates immediately from hot surface of the heating coil. Keep running dry for a
couple of seconds until the
SAFE
warning is displayed. Caution, Never run dry for more than
90s!
5) Close the drain device, and fill the tank with water. The STB resets automatically once
temperature resumes to below designated limit value.
Caution, Risk of burn hazard and liquid spillage!
Do not touch hot surface of the heating coil! Keep away from dripping hot liquid or
evaporating hot steam! Use protective gloves or glasses if necessary!
Never run dry for more than 90s! Overheating of the coil may damage the heater or
degrade its insulation strength!
The first time powering up after repairing or standstill for long period, or at 6 months
intervals under normal use, check the functionality of the following parts or
components:
Cutout capability of the safety temperature limiter (STB)!
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