Water Reduction - Nilfisk-ALTO NEPTUNE 4 FA Service Manual

C
B
Fig.D.7: By-pass pressure
The by-pass pressure is determined of the spring tension in valve "A".
The tension is fixed and will bring out a by-pass pressure in about 30 - 35 bar.
Valve "A" also secures the self suction ability.
The cut off pressure when the gun is released, is determined of the adjustment screw "B".
When the screw is tightened the cut off pressure will rise and by loosening it the pressure will
drop.
The safety valve "C" has no function under normal circumstances. The pressure of the safety
valve is set to about 25 - 30 bar above the cut off pressure.
The safety valve will open if the by-pass valve is stocked and lead water to the suction side of
the pump.
Fig.D.8: Water reduction
When the water regulation "G" is turned counter clock wise, the seat "H" opens and the
water runs both to the outlet of the by-pass housing and in by-pass to the suction side of
the pump.
The pressure "K" will drop depending of the size of the opening in seat "H".
NEPTUNE 4 FA_EN_Ver.2.0_ 22/11
Function
A
F
E
D
C
B
A
G
H
K
I
D
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