Grundfos MQ Operating instructions

GRUNDFOS
ILLUSTRATED SERVICE INSTRUCTIONS
MQ
50/60 Hz

2
Contents
Fitting the non-return valve in the suction port .................................................................... 2
Dismantling the pump.......................................................................................................... 3
Assembling the pump........................................................................................................ 10
Replacing the capacitor..................................................................................................... 18
Replacing the flow sensor ................................................................................................. 20
Replacing the pressure switch........................................................................................... 24
Replacing the non-return valve of the outlet...................................................................... 27

3
Fitting the non-return valve
in the suction port
Remove the suction port.
1
Fit the non-return valve into the suction port.
2
Fit and tighten the suction port.
3

4
Dismantling the pump
Remove the screw of the clamp.
1
Remove the clamp.
2
Remove the screws of the pump sleeve.
3
Loosen the pump sleeve using a screwdriver.
4

5
Remove the pump sleeve.
5
Pull out the self-priming part.
6
Remove the inlet part.
7
Remove the O-ring from the self-priming part.
8
Pull the valve seat out of the self-priming part.
9
Remove the O-ring from the valve seat.
10

6
Remove the O-ring from the inlet part.
11
Remove the plug in the middle of the motor cover.
12
Hold the shaft with a screwdriver.
13
Slacken the impeller nut while holding the shaft.
14
Remove the washers.
15
Remove the impellers and chambers.
16

7
Remove the washers.
17
Pull off the rotating shaft seal part using two screw-
drivers.
18
Remove the stationary shaft seal part if the motor is
not to be pulled out.
19
Insert a screwdriver between the pump housing and
the rubber ring, and prise out the stationary shaft seal
part.
20
Pull the rubber ring out of the pump housing using a
screwdriver, and remove both rings.
21
Remove the four screws of the terminal box cover.
22

8
Take off the cover.
23
Remove the screws of the control unit.
24
Remove the retaining clip of the capacitor.
25
Disconnect the red and white motor conductors from
the capacitor.
26
Disconnect the blue motor conductor from the terminal
block.
27
Slacken the screw which fixes the earth conductor of
the motor.
28

9
Loosen the cover of the pressure tank with a light
blow.
29
Unscrew the pressure tank.
30
The pressure tank.
31
Remove the screws of the end cover.
32
Remove the four screws in the hole for pressure tank.
33
Disengage the end cover from the pump using a
screwdriver.
34

10
Pull out the motor conductors.
35
Push out the motor.
36
Remove the O-ring from the motor.
37
Remove the O-ring on the shaft using a screwdriver.
38
Remove the stationary shaft seal part if it has not been
removed (picture 19).
39
Remove the rubber ring.
40

11
Assembling the pump
Lubricate the O-ring for the motor shaft with O-ring
grease, and fit it on the shaft.
1
Fit the O-ring on the motor, and lubricate it with O-ring
grease.
2
Push the motor home in the pump housing.
3
Take the motor conductors through the hole into the
terminal box.
4

12
The conductors enter the terminal box through the
bottom.
5
Lubricate the O-ring of the end cover with O-ring
grease.
6
Fit the end cover.
7
Lubricate the O-ring of the pressure tank with O-ring
grease.
8
Screw the pressure tank into the hole. Tighten the
pressure tank by hand.
9
Fit the cover on the pressure tank.
10

13
Connect the motor conductors to the capacitor. The
red conductor together with the blue one. The white
one by itself.
11
Fit the blue conductor from the motor into the terminal
block, and fix it.
12
Fit the retaining clip on the capacitor.
13
Fasten the control unit.
14
Tighten the screw to fix the earth conductor.
15
Fit the terminal box cover with the four screws.
16

14
Spray soapy water on the shaft.
17
Fit the stationary shaft seal part on the shaft.
18
Press the stationary shaft seal part home in the pump
housing with a punch.
19
Fit the rotating shaft seal part on the shaft.
20
Push the rotating shaft seal part against the stationary
part using a punch.
21
Fit the washers on the shaft.
22

15
Fit the first chamber.
23
Fit the first impeller.
24
Fit an O-ring on each of the remaining chambers.
25
Lubricate the O-rings with O-ring grease.
26
Fit the remaining chambers and impellers.
27
Fit the washers and the impeller nut on the shaft.
28

16
Hold the shaft with a screwdriver.
29
Tighten the impeller nut while holding the shaft with
the screwdriver. Tightening torque: 7 Nm.
30
Fit the O-rings on the inlet part.
31
Lubricate the O-rings with O-ring grease.
32
Lubricate the O-ring of the self-priming part.
33
Fit the inlet part in the self-priming part.
34

17
Fit the O-ring on the valve seat, and lubricate it with O-
ring grease.
35
Fit the valve seat in the self-priming part.
36
Fit the self-priming part in the pump sleeve.
37
Fit the O-ring on the pump housing.
38
Lubricate the O-ring with O-ring grease.
39
Fit the pump sleeve to the pump housing with the
holes opposite the holes in the pump housing.
40

18
Fasten the pump sleeve.
41
Fit the clamp on the pump.
42
Fit the screw in the clamp and tighten.
43
Fit the plug into the end cover.
44
Tigten the drain plug lightly.
45

19
Replacing the capacitor
Remove the screws of the terminal box cover.
1
Take off the terminal box cover.
2
Remove the screw between the earth terminals.
3
Remove the other screw in the control unit.
4

20
Remove the retaining clip of the capacitor.
5
Remove the conductors from the capacitor. Note their
colour and position.
6
Connect the conductors with the new capacitor. The
red conductor together with the blue one. The white
one by itself.
7
Fit the retaining clip of the capacitor.
8
Fix the control unit and earth terminals with two
screws.
9
Fit the terminal box cover.
10