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Astell Autoclaves/Sterilisers – AMB220 | AMB230 | AMB240 | AMB420 | AMB430 | AMB440 | AMA240 | AMA440
FILLING WITH WATER
CLASSIC MODELS
The machine is fitted with a conductivity sensing water
detection system. This shows water level with a fill with
water message.
If demineralised or distilled water is used for initial filling,
the “fill with water” display may stay on even if the water
level is adequate. Should this happen, add 0.5 - 1 litre of
hard tap water. This should provide sufficient conductivity
to activate the sensor system.
The system senses the conductivity of the water via a
“high level” probe. The probe is set at a reserve level
and the chamber must be filled, to this level to ensure
sufficient water to complete a sterilize cycle. This water
detection operates when the machine is not running,
i.e. when the cover is open, or before pressing “start”.
This water reserve level is set to permit adequate free
steaming.
• Open the chamber and pour in water
• Add water to the chamber until the fill with water
display disappears
• The water-level in the chamber will then reach the high
level probe, sufficient for a cycle. It is not possible to
start the machine in the low water condition
• The chamber should not be over-filled
• It is best to pour in the water fairly slowly. If too much
water is added or it is poured in too quickly frontload
models will overflow and top-load models will not heat
correctly
• The control system monitors the water level and
prevents starting unless there is enough water to
complete a typical cycle
WATER LEVEL - VISUAL CHECK
• Frontload models: The correct level is the point where
the water just reaches within 0.5-1cm of the front lip of
the chamber
• Top-load models: Lift out the load support plate or
lower shelf. The filling level is correct when the tip of
the water level probe dips about 3 mm under the water
surface
Note:
The temperature sensor is the 3mm diameter
stainless rod which projects approx. 110 mm into the
chamber. This must be above the- water.
AUTOFILL MODELS
The steriliser uses water held in the internal tank with a
removable cover.
Tank filling level
Inside the tank there is a stainless steel plate, near the top
and visible through the open cover. The top surface of this
plate indicates the maximum water filling level.
DO NOT FILL ABOVE THIS LEVEL
The control system monitors the water level in the tank
using a built in float switch and prevents starting unless
there is enough water to complete a cycle.
WATER QUALITY
Untreated tap water of drinking quality is satisfactory
in this steriliser although the use of treated or partially
demineralised water is acceptable, particularly in extreme
hard water areas. This will help reduce furring on the
elements the water must be conductive, requiring ionic
content.
Deionised or distilled water is not acceptable.
The water used must be conductive, i.e. have an ionic
content. Tap-water of drinking quality is suitable.
Deionised or distilled- water will not work in this steriliser
unless a suitable ionic salt is added. Please consult your
dealer for advice if you wish to use treated water.
Water and electrical safety
During filling if a spillage of water penetrates
the cabinet or vent holes, stop using the
steriliser. Turn off at the power source, mop
up the water and call a service engineer
immediately.
Soft water
Water that has been chemically softened is
usually acceptable, but water that is from a
naturally soft source may be unsatisfactory.