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Scale deposits should be removed from all internal surfaces,
particularly the heating element, thermistors and level sensors by
gently tapping or scraping. If the deposits are soft, use a nylon
pad and flush out. Abrasive cleaning materials containing scouring
powders and detergents must not be used, such materials can
cause taste problems.
Suitable chemical de-scalants must only be used in accordance
with the manufacturers recommendations. This will prevent health
and safety issues, taste problems and potential damage to the
appliance. All trace of these chemicals must be removed before re-
commissioning the unit. Misuse of such chemicals is not covered by
the product warranty.
IMPORTANT Before re-commissioning the boiler it is
important that all scale and moisture is removed from the level
sensors and insulating gaskets, to avoid a false signal being
transmitted through the scale to the boiler body. Failure to
remove this scale and/or moisture could cause the sensor to
indicate to the PCB that water is covering the element, whether
or not water is present. In this situation the PCB could energise
the element causing failure. If in doubt, protect the element by
hand filling with water to the level of the draw-off tap before
switching on the electrical supply to the boiler.
General function
The printed circuit board (PCB) controls the heating and filling
functions of the boiler by monitoring the thermistors and level
sensors. The PCB also controls the external light unit to indicate
the current state of the boiler. Red and yellow LED’S on the circuit
board indicate whether the PCB has energised the elements or
solenoid respectively.
Should an element fail and need to be replaced, it may be
