Pool Controls Chemigem D10 User Manual page 25

Low pH – (Excess Acid)
If the pH of the water drops below the set point, a red status indicator will be illuminated
and the words "LOW pH" will be displayed on the LCD.
The ChemiGem will automatically prevent any further acid being added to the pool until the
pH is brought back into the correct range by the addition of sodium carbonate or sodium
bicarbonate.
Possible causes include:

Manual overdosing

Excessive rainfall

Faulty solenoid valve or peristaltic pump

The multi-electrode (probe) may require cleaning (see page 24 for details)

Low Total Alkalinity

Poor pool water circulation
Safety Shutdown
If the pH falls below 5.8 the ChemiGem will shut down pump operation to ensure no more
acid gets into the pool.
High pH – (Insufficient Acid)
If the pH rises significantly higher than the set point, a red status indicator will be
illuminated and the words HIGH pH will be displayed on the LCD.
Note that a high pH can drastically reduce the ORP of the pool water, and therefore reduce
the effectiveness of the sanitiser. It is important to restore the pH balance as soon as
possible by adding acid to the pool.
Possible causes include:

The acid drum is empty

The pool has been superchlorinated recently

The pool has a new plaster lining (very alkaline) demanding more acid than can
be supplied by the ChemiGem

Faulty solenoid valve

Filter requires backwashing

Multi-electrode (probe) may require cleaning (see page 24 for details)

Injector nozzle is blocked

Venturi system (if fitted) is blocked
If each of these factors is addressed, the ChemiGem
set level is achieved – at which point the status indicator will revert to green and the
warning will no longer be shown on the LCD.
®
will dose the pool with acid until the
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