Piping Requirements - Xylem LOWARA ESH ATEX Manuel D'installation, D'utilisation Et Entretien

protected from any fluid leaks, or flooding.
•
If possible, place the pump slightly higher
than the floor level.
•
The ambient temperature must be
between -10°C (+14°F) and +55°C
(+131°F).
•
The relative humidity of the ambient air
must be less than 95% at +40°C
(+104°F).
Contact Xylem or the Authorised Distributor if:
•
The relative air humidity conditions
exceed the guidelines.
•
The room temperature exceeds +55°C
(+131°F).
•
The unit is located more than 1000 m
(3000 ft) above the sea level. The motor
performance may need to be de-rated or
replaced with a more powerful motor.
For information about which value to de-rate the
motor with, see Table 12.
Pump position and clearance
Provide adequate light and clearance around
the pump. Make sure that it is easily accessible
for installation and maintenance operations.
Installation above liquid source (suction lift)
The theoretical maximum suction height of any
pump is 10.33 m. In practice, the following affect
the suction capacity of the pump:
•
Temperature of the liquid
•
Elevation above the sea level (in an open
system)
•
System pressure (in a closed system)
•
Resistance of the pipes
•
Own intrinsic flow resistance of the pump
•
Height differences
•
The following equation is used to calculate
the maximum height above the liquid level
which the pump can be installed:
(pb*10.2 - Z) ≥ NPSH + Hf + Hv + 0.5
pb Barometric pressure in bar (in
closed system is system
pressure)
NPSH Value in meter of the pump
intrinsic flow resistance
Hf Total losses in meters caused by
passage of liquid in the suction
pipe of the pump
Hv Steam pressure in meters that
correspond to the temperature of
the liquid T°C
0.5 Recommended safety margin (m)
Z Maximum height at which the
pump can be installed (m)
(pb*10.2 - Z) must always be a
positive number.
For more information, see Figure
12.
NOTICE:
Do not exceed the pumps suction capacity as
this could cause cavitation and damage the
pump.

4.2.2 Piping requirements

Precautions
WARNING:
• Use pipes suited to the maximum
working pressure of the pump.
Failure to do so can cause the
system to rupture, with the risk of
injury.
• Have all the connections made by
qualified installers in compliance
with the regulations in force.
NOTICE:
Observe all regulations issued by authorities
having jurisdiction and by companies
managing the public water supplies if the
pump is connected to a public water system. If
required, install appropriate backflow-
prevention device on the suction side.
Piping checklist
Check that the following requirements are met:
•
All piping is independently supported,
piping must not place a burden on the
unit.
•
Flexible pipes or unions are used, in order
to avoid transmission of pump vibrations
to the pipes and vice versa.
•
Use wide bends, avoid using elbows
which cause excessive flow resistance.
•
The suction piping is perfectly sealed and
airtight.
•
If the pump is used in an open circuit,
then the diameter of the suction pipe is
suited to the installation conditions. The
suction pipe must not be smaller than the
diameter of the suction port.
•
If the suction piping must be larger than
the suction side of the pump, then an
eccentric pipe reducer is installed.
•
If the pump is placed above liquid level, a
foot valve is installed at the end of the
suction piping.
•
The foot valve is fully immersed into the
liquid so that air cannot enter through the
suction vortex, when the liquid is at the
minimum level and the pump is installed
above the liquid source.
•
Appropriately sized on-off valves are
installed on the suction piping and on the
delivery piping (downstream to the check
valve) for regulation of the pump capacity,
for pump inspection, and for maintenance.
•
Appropriately sized on-off valve is
installed on the delivery piping
(downstream to the check valve) for
regulation of the pump capacity, for pump
inspection, and for maintenance.
•
In order to prevent back flow into the
pump when pump is turned off a check
valve is installed on the delivery piping.
en - Original instructions
25