Cleaning The Solenoid Valve - Grundfos AQtap Service Instructions With Installation And Operating Instructions

16. Cleaning the solenoid valve

WARNING
If the solenoid valve is continuously operated, the
surface can be hot. Make sure that persons cannot
accidentally come into contact with hot surfaces.
Cleaning and maintenance intervals
Clean and maintain the solenoid valve in the following intervals:
• At least every 12 months.
• In the event of a fault.
Dismounting the solenoid valve
1. Prepare the AQtap for internal servicing, see section
17.3 Preparing the AQtap cabinet for internal servicing.
2. Dismount the solenoid valve, see section 17.6 Replacing the
solenoid valve (valve kit, complete).
Disassembling and cleaning of the solenoid valve
See exploded view Fig. 2 for identification and placement of
parts.
1. Disconnect the coil plug (3).
2. Remove the retaining clip (1) and slip the coil (2) off the
solenoid base subassembly (5).
When the retaining clip (1) disengages, it can spring
Note
upwards.
3. Remove the spring washer (4) and unscrew the solenoid base
sub assembly (5) from the bonnet (8), remove its O-ring (6).
4. Unscrew the bonnet screws (7) and remove the bonnet (8).
Remove the spring (9) and the diaphragm/core-assembly
(10).
5. Remove the valve body O-ring (11).
– All parts are now accessible for cleaning.
6. Clean all parts and examine for excessive wear.
– Replace the complete solenoid valve, if necessary.
Reassembling the solenoid valve
Reassemble in reverse order of disassembly. See exploded view
Fig. 2 for identification and placement of parts, and see Torque
chart for the required torques.
Lubricate all O-rings with drinking water approved
Note
high quality silicone grease.
1. Replace the valve body O-ring (11).
2. Replace diaphragm/core-assembly.
Locate the pilot hole (10a) in diaphragm/core-
Caution
assembly (10) at 45 degrees from the solenoid valve
outlet.
3. Install the spring (9) properly into the core of the diaphragm/
core-assembly (10).
4. Replace the bonnet (8) and bonnet screws (7). Torque the
bonnet screws (4x) in a crisscross manner according to the
torque chart.
5. Replace the solenoid base sub-assembly O-ring (6) and the
solenoid base sub-assembly (5), and torque according to the
torque chart.
6. Replace the spring washer (4), coil (2) and retaining clip (1).
7. Connect the coil plug (3) and torque the screw according to
the torque chart.
Mounting the solenoid valve
1. Mount the solenoid valve, see section 17.6 Replacing the
solenoid valve (valve kit, complete).
2. Complete the cleaning of the solenoid valve in the same way
as for internal servicing of the AQtap, see section
17.14 Completing steps after internal servicing.
3. Operate the solenoid valve a few times to make sure that it
operates properly.
26
1
2
3
4
5
6
7
8
9
10
11
12
Fig. 2 Solenoid valve, exploded view
Legend
Pos. Description
1 Retaining clip
2 Coil & nameplate
3 Coil plug
4 Spring washer
5 Solenoid base sub-assembly
6 O-ring, s.b.sub-assembly
7 Screw (4x)
8 Bonnet
9 Spring
10 Diaphragm/core-assembly
10a Pilot hole
11 O-ring, valve body
12 Solenoid valve body
Torque chart
Pos. Torque in Nm
A 0.6 ±0.2
B 20 ±3
C 5.6 ±0.5
A: Torque [Nm]
0.6 ± 0.2
A
B
C
C: Torque [Nm]
5.6 ± 0.5
10a