Dynalab A4000D - Manuel (Page 15)

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The following instructions apply to the
A4000D double distillation stills where
the water feed to the first stage boiler is
either via the mains supply or a header
tank.
If it is desired to feed the first stage
boiler with deionised or pre-treated
water to obviate cleaning, then the
instructions on page 15 should be
followed.
1 Before switching ON either mains
electricity or water supply, identify
the control switches and indicator
lights on the front of the cabinet.
Green Light
When illuminated this shows there
is mains supply voltage within the
unit. In no circumstances should
the cabinet end-panel be removed
when this light is illuminated.
White “On/Off” Switch
The primary switch for controlling
water and electricity inside the still.
The switch illuminates when
pressed in the ON position.
Amber Light
When illuminated, this indicates
that the distillate collection
reservoir is full, as detected by the
level control.
White “Clean” Switch
This shuts off the heating elements
but allows water to flow into the
boiler. Used for filling the boiler on
commissioning and cleaning
purposes. The switch illuminates
when pressed in the ‘ON’ position.
2 Carefully check the following:–
– That the appropriate electricity,
water and drain services have
been provided. If in doubt,–
consult the “Location and
Services” notes on page 1.
– Water still ON/OFF switch is in
the OFF position.
i.e. – switch should not be
pressed and should not
illuminate.
– Water still CLEAN switch is in the
ON position.
– The Rotaflo stopcock on the
front boiler level control WL48 is
closed.
– The float switch on the second
stage boiler level control W4L2A
is set at the factory. However,
check that this has not been
disturbed during transit. A rough
check is that the distance from
the top of the large screw cap of
the W4L2A to the top of the
glass guide tube should be
approximately 15-20mm see fig.
10.
– The dummy shorting plug is
fitted to socket item 7, fig. 7.
3 Switch on the electricity supply.
(Note: the green indicator light will
illuminate).
4 Press the ON/OFF switch to the ON
position (switch will illuminate).
5 Re-check that the Clean switch is in
the ‘ON’ position (switch will
illuminate).
6 Turn on the mains water supply
and using the needle valve, item
18, fig. 7, on the side of the
cabinet, adjust the flow rate to
approximately 2 litres/minute.
Check there are no water leaks
from the hose connectors.
7 Observe that the front boiler is now
filling with water to cover the
heating elements. When the water
has reached the pre-set level excess
will be discharged to drain. Check
that the drain water flows freely
and does not “back-up” into the
level control.
8 Press the Clean button to ‘OFF’
position. (Switch light should go
out).
The heater on the front boiler
should start to warm up and
eventually run with a red glow.
After a short time distilled water
will emerge from the outlet pipe
item. This should feed into the
empty rear boiler via the level
control W4L2A.
9 Allow the rear boiler to fill with
single distilled water (for approx.
20 to 30 minutes), keeping an eye
on the level. Note that the heater
of the second stage only comes on
when the level of single distilled
water in the rear boiler is at about
the equator. It may be necessary to
adjust the level of the float switch
of the WL42A to achieve this
condition. Refer to fig. 10.
Lifting the guide tube increases the
level at which the heating element
will switch on.
Lowering the guide tube decreases
the level at which the element will
switch on.
Double distilled water ultimately
flows from outlet pipe, item 19.
This should fall away from the still
with no kinks, restrictions or U
bends.
10 To avoid excessive wastage of
coolant water, make further
adjustments to the needle valve,
item 18. Slowly reduce the flowrate
until the flow control, item 15,
switches off the heaters - then
increase the flow until the power is
restored.
11 Safety Cut-Outs
All Aquatron water stills are
protected by the following safety
devices.
Flow Control Switch (item 15)
monitors the flow of coolant water
into the still and shuts off the
heating elements, if the flow is
insufficient.
Thermostat Cut-Out (item 24)
In normal operation the water
within the glass will be at 100°C. In
single fault conditions, i.e. in the
event of water supply failure, the
content will increase to 110°C
where upon a resettable thermostat
will operate. Once switched, the
thermostat has to be manually
reset. This is achieved by
unscrewing the black knob, fig. 7,
item 26, located inside the cabinet
and pressing the reset button.
Reservoir Control (fig. 11)
is positioned on the collection
reservoir and switches off both the
electricity and water supply when
the reservoir is full of distilled
water. The water supply is only shut
off around 7 mins. after the
reservoir is full to allow the heating
elements to cool.
It is recommended that the
operation of the flow switch and
reservoir control be checked on a
regular basis.
a) Simulation of Mains Water
Supply Failure
Turn off the mains water supply
at the tap. This should switch of f
the heating element. Turning the
tap on again will switch the
heaters on.
b) Simulation of Reservoir Full
Condition
Lower the glass pressure bell
WFB, fig. 11, into the distillate to
a depth of 150mm. This will
switch off the heating element
immediately and the cooling
water after 7 minutes. Raising
the bell will cause both to be r e-
supplied.
12 Switching Off
Push the CLEAN switch to the ON
position. Wait until the residual
heat contained in the heating
elements has dispersed and no
boiling is evident. Turn off water
supply. Push ON/OFF switch to OFF
position. Isolate from mains
electricity supply.
A4000D Operation