Minimum Flow Rate; Electrical Data; Maximum Number Of Starts; Installation - Grundfos CRK Serie Instrucciones De Instalación Y Funcionamiento

5.3 Minimum flow rate

Due to the risk of overheating, the pump should not
be used at flows below the minimum flow rate.
The curve below shows the minimum flow rate as a
percentage of the nominal flow rate in relation to the
liquid temperature.
Q m i n
[ % ]
3 0
2 0
1 0
0
4 0 5 0 6 0 7 0 8 0 9 0 1 0 0 1 1 0 1 2 0
Fig. 5 Minimum flow rate in relation to
temperature
The pump must never operate against a
Note
closed discharge valve.

5.4 Electrical data

See motor nameplate.

5.5 Maximum number of starts

Motor size Recommended maximum
[kW] number of starts per hour
0.06 - 0.18
0.25 - 2.2
3-4
5.5 - 11
15-22
30-45
10

6. Installation

6.1 Pump location

The pump is designed for tank mounting in vertical
and horizontal position. However, only MTR version
H and MTRE version H are suitable for horizontal
mounting.
The pump is positioned in a hole cut into the tank
and is secured to the tank by four hexagon head
screws through the holes in the mounting flange.
t [ ° C ]
On horizontally installed MTR, MTRE pumps with
motors from 5.5 kW and up the motors have feet and
must be supported.
100
250
100
50
40
8
Warning
The pump must be installed so that
persons cannot accidentally come into
contact with the hot surface of the motor.
Vertical
Fig. 6 Vertical and horizontal installation
Fig. 7 Horizontally installed MTR with foot
For horizontally mounted pumps ensure a
sufficient sealing between pump flange
Caution
and tank. A sealing gasket will usually
suffice.
Before changing shaft seals for
Caution horizontally mounted pumps, drain the
tank.
MTR 32, 45 and 64 pumps can only be
Caution
installed in vertical position.
Horizontal