DAYLIFF SUNVERTER 3 Installation & Operating Manual page 35

PROBLEM
Frequent starts
and stops
Long delay before
water flows after
start
Loud noise in the
pipework
Mechanical
damage to pump
and motor
POSSIBLE CAUSE
The water level sensor not installed
correctly
The non-return valve is leaking or stuck
half open
The pump is oversized for borehole
Riser pipe leakage
Pump non return valve faulty
Water hammer
Pump activation due to low system head
resulting in operation at insufficient
pressure
SOLUTION
Check water level sensor and correct
Pull out the pump and clean or replace
the non-return valve
Increase the installation depth of the
pump, throttle the pump or replace it
with a smaller model to obtain a smaller
capacity
Check and repair riser pipe
Lift pump and rectify
Fit a surface non-return valve and a
diaphragm tank on the surface delivery
piping
Throttle the pump or replace it with a
lower pressure alternative
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