19
1.
Shut off and drain the still.
2.
Shut off the water supply to the still.
3.
Remove the condenser from the still.
Inspect the cooling water side of the
condenser for scale and clean as re-
quired. If required, clean the distilled
water side of the condenser as
described under “Biological Cleaning.”
4.
Disassemble until the interior of the
evaporator is visible. The evaporator
cover, high purity chamber and pre-
heater (if supplied) may be removed
as a unit and the interior of the evapo-
rator will be visible. Inspect the interior
of the evaporator for scale. Remove
as much scale as possible manually.
5.
Disassemble the drain line and clean
as required. Ensure that the drain line
is clear (including the drain opening in
the evaporator) before using detergent
or acid cleaners. Reassemble the
drain line.
6.
Soft scale may be removed as
described under “Soft Scale
Removal.” Silica scale may be re-
moved as described under “Silica
Scale Removal.” To remove hard
scale or organic scale, fill the evapora-
tor with concentrated acid (see “Hard
Scale Removal”) or detergent solution
(see “Organic Scale and Sludge Re-
moval”) or detergent solution (see
“Organic Scale and Sludge Removal”)
as required.
M
AINTENANCE AND
S
ERVICING
Note
Stills equipped with a high purity
chamber or preheater should
not be cleaned with acid unless
the high purity chamber can be
removed. The fumes given off
by the acid may damage the tin
coating used in these
accessories.
