Plumbing Design - Lorentz PS Série Manuel D'installation Et De Fonctionnement

52 Pump Installation

8.5.5 Plumbing Design

CAUTION – New pumps are covered with
foam plugs to prevent contamination.
Remove the foam plugs before connecting
pipes.
CAUTION – Handle the pump with caution,
never use force on it.
Minimize suction lift – to max. 3 m total pressure loss
(2 m for pumps with flow rate greater than 400 l/h (105 US
Gal)). The less suction lift, the more reliable and quiet the
pump will be. The motor may not be submerged, this will
damage the pump.
Intake pipe – The intake pipe may run any reasona-
ble horizontal distance, although it is best to keep it short.
Use large pipe for the intake (1 to 1 ½" for larger booster
pumps). Slope the intake line from the water source up to-
wards the pump. Avoid humps in the intake line that cause
air pockets which can block the flow.
CAUTION – Avoid leaks in the suction line.
The pump will prime insufficiently or not
at all.
The intake pipe must be sized generously to avoid high
pressure drop at peak flow rate, or the pump will be noisy
and will wear rapidly.
Use pipe reducer fittings to adapt the pumps' inlet or outlet
to larger pipe size where necessary. Larger pipe sizing does
not have a negative effect.
CAUTION – The intake must not be
restricted by undersized pipe, excessive
suction lift, or a clogged filter.
CAUTION – Excessive suction at the pump
intake causes cavitation, resulting in noise
and rapid pump wear.
CAUTION – Do not use thin wall hose or
soft tubing on the pumps' intake. It may
collapse under suction and restrict the
flow.
CAUTION – Do not use polyethylene pipe
for the suction side. It is prone to leakage
at the fitting.
Inline filter – Inline filters should be mounted horizontal-
ly and as low as possible. This prevents any air trapped from
blocking the water flow.
Foot valve – The foot valve is a check valve installed at the
water intake. It is required in any situation where the pump
is located higher than the lowest water level of the wa-
ter source. A high quality spring loaded type is recommend-
ed to avoid loss of prime. A check valve allows water to flow
one way only.