English (GB)
7
4.1 Pumped liquids
Thin, clean, non-aggressive and non-explosive
liquids, not containing solid particles or fibres that
may attack the pump mechanically or chemically.
Examples:
• central heating system water (the water should
meet the requirements of accepted standards on
water quality in heating systems)
• cooling liquids
• domestic hot water
• industrial liquids
• softened water.
The pumping of liquids with a density and/or
kinematic viscosity higher than that of water will
cause
• a considerable pressure drop
• a drop in hydraulic performance
• a rise in power consumption.
In such cases, the pump should be fitted with
a bigger motor. If in doubt, contact Grundfos.
The EPDM O-rings fitted as standard are primarily
suitable for water.
If the water contains mineral/synthetic oils or
chemicals or if other liquids than water are pumped,
the O-rings should be chosen accordingly.
5. Installation
The pump must be sited in a dry well ventilated, but
frost-free position.
When installing pumps with oval bolt holes in the
pump flange (PN 6/10), washers must be used as
shown in fig. 5.
Fig. 5 Use of washers for oval bolt holes
Arrows on the pump housing show the direction of
flow of liquid through the pump.
Pumps with motors smaller than 11 kW can be
installed in horizontal or vertical pipework.
Pumps with motors of 11 kW and up may only be
installed in horizontal pipework with the motor in
vertical position.
For inspection and motor/pump head removal, the
following clearance is required above the motor:
• 300 mm for motors up to and including 4.0 kW.
• 1 metre for motors of 5.5 kW and up.
See fig. 6.
Fig. 6 Required clearance above the motor
Twin-head pumps installed in horizontal pipes must
be fitted with an automatic air vent in the upper part
of the pump housing. See fig. 7.
The automatic air vent is not supplied with the pump.
Fig. 7 Automatic air vent
If the liquid temperature falls below the ambient
temperature, condensation may form in the motor
during inactivity. In this case, it must be ensured that
the drain hole in the motor flange is open and points
downwards. See fig. 8.
Fig. 8 Drain hole in motor flange
If twin-head pumps are used for pumping liquids with
a temperature below 0 °C/32 °F, condensed water
may freeze and cause the coupling to get stuck.
The problem can be remedied by installing heating
elements. Whenever possible (pumps with motors
smaller than 11 kW), the pump should be installed
with the motor shaft in horizontal position. See fig. 7.
Warning
When pumping hot or cold liquids,
ensure that persons cannot
accidentally come into contact with hot
or cold surfaces.
TM01 0683 1997
The motor must never fall below the
horizontal plane.
TM00 3733 2802TM03 8127 0507TM00 9831 3202
The technical data in section 9. must be
observed.
5.5 - kW0.25 - 4.0 kW
1 m
300 mm
0.25 - 4.0 kW 5.5 kW and up
To Next Page
Loading...
