Grundfos MAGNA 2000 Series, Installation And Operating Instructions Manual

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Fig. 2 Changing the control box position
4.3 Twin-head pumps
Twin-head pumps are supplied fitted with a GENI
module on each control box. The modules are
connected via a cable. The modules determine the
operating mode of the pump, see section
7.12.1 Control of twin-head pumps .
The automatic air vent is not supplied with the pump.
Fig. 3 Automatic air vent
4.4 Non-return valve
If a non-return valve is fitted in the pipe system,
see fig. 4, it must be ensured that the set minimum
discharge pressure of the pump is always higher
than the closing pressure of the valve. This is
especially important in proportional-pressure control
mode (reduced head at low flows).
Fig. 4 Non-return valve
4.5 Frost protection
If the pump is not used during periods of frost,
necessary steps must be taken to prevent frost
bursts.
T
M
02
55
07
34
02
Pos. Description
1 Inspection screw
2 Screw
3 Stator housing/control box
4 Rotor
5 T-key
6 O-ring
Caution
Twin-head pumps mounted in
horizontal pipes must be fitted with an
automatic air vent (Rp 1/4) in the upper
part of the pump housing, see fig. 3.
T
M
03
88
31
26
07
5
4
6
TM
0
2
0
640
0
301
Note
Additives with a density and/or
kinematic viscosity higher than those/
that of water will reduce the hydraulic
performance.