30
to replace the porous plate
It should be noted that replacement of the porous plate is rarely necessary; however, should the plate
become blocked or damaged the following instructions should be followed.
a) Empty the unit of alumina as in 1 above.
b) Remove the jar (13) and turn the unit on its back.
c) Disconnect the air line to the air supply point on the inside of the chassis (6) by unscrewing the
knurled nut and pulling the plastic pipe clear.
d) Remove eight nut and lock washers holding the chassis (6) to the LH wrapper (2), RH wrapper
(3) and central wrapper (55), one bolt and lock washer situated in the recess for the dust
extraction jar (13), and two lock nuts on the stud of the plenum chamber (42). Pull chassis
clear.
e) Remove 25 nuts, bolts and washers securing plenum chamber (42) to the inner container (41).
Pull the plenum chamber clear and remove the porous plate (43).
f) Clean any sealant from the flanges of the plenum chamber and inner container. A seal of Red
Hermetite should be placed on both of the above flanges when fitting a new porous plate. Fit
the porous plate while the seal is still wet, ensure that the porous plate and plenum chamber
are correctly aligned with the offset hole in the inner container assembly.
g) Refit the 25 nuts, bolts and washers and tighten them to a torque of 2.25-2.7 Nm (20-24 lb ins).
h) Reverse the operation for replacing the chassis.
to replace the Flowmeter tube
a) Remove the protective cover.
b) Remove the flow tube by first removing the plastic clip at the top of the flow tube, lift the flow
tube up and remove the bottom of the tube clear of the flowmeter assembly. Pull the tube
downwards from the top insert.
c) Fit the float with the pointed end down, into the tube.
d) Push the tube on to the top insert, line the tube with the bottom insert, pull the flow tube and
the top insert down until the flow tube is fully engaged on the bottom insert, refit the plastic
clip.
e) Refit the protective cover.
to replace the Fluidisation pressure switch (57)
This is preset to cut off the electrical supply to the heater should the fluidisation air flow fall below 2 1/
min. It is secured to the central wrapper (55) Remove the top panel (1) by removing the screw at the left
hand bottom corner, push up and pull out the panel. Remove the three screws securing the front panel
(5) along the upper edge. DO NOT DISTURB SCREW WITH EARTH SYMBOL ALONGSIDE IT. Remove the
knurled nut from the extraction air switch (22) and lower the panel.
to replace the Fuse
A high speed fuse (18) is fitted in the fuse holder (17) on the front panel (5).
to replace the triac/ssr
Remove the top panel (1) by removing the screw at the left hand bottom corner, push up and pull out
the panel. Remove the three screws securing the front panel (5) along the upper edge. DO NOT DISTURB
SCREW WITH EARTH SYMBOL ALONGSIDE IT. Remove the knurled nut from the extraction air switch (22)
and lower the panel. Remove the wiring from the triac (24), and remove the retaining screws. Fit the new
triac, first smearing it with heatsink compound. Re-fit the wires and replace the front panel.
