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OPERATOR MAINTENANCE
Before any servicing is attempted the unit should be disconnected from the mains power supply and allowed to
cool down. In all cases maintenance and repair work should be undertaken only by a skilled technician. Untrained
personnel should not attempt to dismantle the instrument.
EMPTYING THE DUST COLLECTION JAR
Empty the dust collection jar as follows (this can be done whilst bath is hot):
1. Turn off the fluidization air.
2. Turn off the dust extraction system.
3. Unscrew the jar from the base of the cyclone unit and remove.
4. Screw on the empty spare jar.
5. Turn on the dust extraction system.
6. Carefully and slowly empty the full jar into the top of the bath. (Except for the first jar from a new charge
which should be thrown away).
Note:
During normal operation, the collection jar should only become partially full during an 8-hour period.
An excessive amount of alumina in the collection jar suggests that the fluidized bath has been overfilled with
alumina; check the level in the bath. Add enough from the jar to bring the bath to the correct level and keep
the remainder as spare material.
7. Increase fluidization up to the correct working level.
8. Check the filter and clean or replace if necessary, when the extraction system is switched off. (Note the
screw and the filter may be hot).
CLEANING THE EXHAUST FILTER
1. Turn off the extraction system.
2. Release the filter housing by removing the retaining screw and vacuum the filter chamber every two weeks
with daily bath use.
3. Replace the filter every 6 months with daily bath use.
PERIODIC MAINTENANCE
The fluidized bath requires the following periodical inspection to be carried out to ensure trouble free operation:
1. The condition of the alumina should be checked to make sure that there are no lumps and, if practical, sieved
occasionally. A fresh charge of alumina should be used if the medium is contaminated in any way.
2. Should the fluidized bath be stored for long periods of time under damp or humid conditions, moisture may
be absorbed by the alumina which is hydroscopic. To avoid violent fluidization which occurs when damp
alumina is heated above 100°C, operate the bath for a period of approximately 8 hours at 90°C prior to
operation at elevated temperatures. The heaters should be checked for discolouration, oxidation or to
determine if any build-up of alumina particles has taken place on the surface.
3. The condition of the porous plate should be checked to see whether there are any oil stains or
discolouration: if so, and fluidization is impaired, replace the porous plate. Contact your local Cole-Parmer
dealer for further information.
