Stuart Turner 28474 User manual

Cont ...
INSTALLATION INSTRUCTIONS
SERVICE KIT - MONSOON NEGATIVE PUMPS (Pre - 2008) Part No. 28474
- N1.5, N2.0 & N3.0 bar variants only.
Note: 1) Quantities are to cover a twin pump, singles use half.
2) See relevant section for detailed instructions.
Fig. 1
24 (Section 2)
Capacitor (note ratings)
25 (Section 3)
PCB
26 (Sections 2, 3 & 4)
Adhesive foam pad
7 (Section 1)
Woodruff key
9 (Sections 1 & 6)
‘O’-ring
(ID 24.6 mm)
3 (Section 1)
Stainless washer
(OD ¾ ")
14 (Section 1)
Screws (M4 x 16 mm)
16 (Section 8)
Clip
4 (Section 1)
Rotary seal
5 (Section 1)
Seal Counterface
6 (Section 1)
‘O’-ring
(ID 66.4 mm)
1 (Sections 1 & 6)
Screws (M6 x 35 mm)
28 (Section 4)
Reed switch
23 (Sections 2, 3 & 5)
Screws (K40 x 16 mm)
29 (Section 4)
Strain relief bush
18 (Sections 1 & 6)
‘O’-ring (ID 15.0 mm)
11 (Section 2)
Non-return
valve assembly
22 (Section 5)
Pressure switch
20 (Section 7)
Pressure vessel (0.6 litre)
19 (Sections 1 & 5)
Rubber washer (G ½ “)
27 (Section 1 & 4)
Reed switch tie wrap
17 (Section 1)
‘O’-ring (ID 14.0 mm)
17
17
21 (Sections 1 & 5)
Bonded seal
15 (Section 8)
Magnetic float
13 (Section 1)
‘O’-ring (ID 19 mm)
2 (Section 1)
Circlip
12 (Section 2)
‘O’-ring
(ID 21 mm)
10 (Section 2)
Non-return
valve holder
8 (Section 1)
Thrower
31 Strainer

- 2 -
Cont ...
• COMPLETE KIT CONTENTS
This kit contains parts for a range of different pump types - please ensure you correctly identify
the relevant parts for the pump being serviced before commencing. Also refer to the relevant
section for detailed instructions for the correct installation of the parts.
Fitting of incorrectly identified parts could lead to pump failure. If in doubt
contact PumpAssist on [phone].
ITEM QTY ITEM QTY
1 Screws (M6 x 35 mm) 8 17 ‘O’-Ring (ID 14 mm) 3
2 Circlip 2 18 ‘O’-Ring (ID 15 mm) 2
3 Stainless Washer (OD ¾ ") 2 19 Rubber Washer (G ½ “) 1
4 Rotary Seal Assembly 2 20 Pressure Vessel (0.6 litre) 1
5 Seal Counterface 2 21 Bonded Seal 1
6 ‘O’-Ring (ID 66.4 mm) 2 22 Pressure Switch 1
7 Woodruff Key 2 23 Screws (K40 x 16 mm) 4
8 Thrower 2 24 Capacitor (1 off each variant) 2
9 ‘O’-Ring (ID 24.6 mm) 4 25 PCB 1
10 Non-Return Valve Holder 2 26 Adhesive Foam Pad 1
11 Non-Return Valve Assembly 2 27 Reed Switch Tie Wrap 2
12 ‘O’-Ring (ID 21 mm) 2 28 Reed Switch 2
13 ‘O’-Ring (ID 19 mm) 2 29 Strain Relief Bush 3
14 Screws (M4 x 16 mm) 4 30 Applicator Tool (not shown) 1
15 Magnetic Float 2 31 Strainer 2
16 Clip 2
Check to see that you have all the above items and that they are not damaged. If any damage is
found contact Stuart Turner Ltd within 24 hours of receipt.
• PUMP PREPARATION
To prepare the pump to accept the service kit parts, each pump part must be removed noting
its exact position and sequence (Fig. 1).
Now clean all the individual parts. Before fitting the new service kit parts, the pump and seal
type must be identified.
• CONTENTS PAGE
Section 1 Mechanical seal replacement .................................. 3
Section 2 Capacitor replacement ....................................... 7
Section 3 Printed circuit board replacement ............................... 9
Section 4 Reed switch replacement ..................................... 13
Section 5 Pressure switch replacement .................................. 16
Section 6 Non-return valve replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Section 7 Pressure vessel replacement ................................... 21
Section 8 Magnetic float replacement ................................... 23
Section 9 Strainer ................................................... 24

- 3 -
Cont ...
SECTION 1 - MECHANICAL SEAL REPLACEMENT
The parts required to replace the seal (one end only) are:
ITEM QTY ITEM QTY
1 Screws, (M6 x 35 mm) 4 9 ‘O’-Ring (ID 24.6 mm x 2.4 mm c/sec) 2
2 Circlip 1 14 Screws (M4 x 16 mm) 4
3 Stainless Washer (OD ¾ ”) 1 17 ‘O’-Ring (ID 14 mm) 2
4 Rotary Seal Assembly 1 19 Rubber Washer (G ½ “) 1
5 Seal Counterface 1 21 Bonded Seal 1
6 ‘O’-Ring (ID 66.4 mm x 1.78 mm c/sec) 1 27 Reed Switch Tie Wrap 2
7 Woodruff Key 1 30 Seal Applicator Tool (not shown) 1
8 Thrower 1
• DISASSEMBLY
To access the mechanical seal assembly the flow switch assemblies must first be removed
(Fig. 2).
Flow Switch Assemblies:-
Fig. 2
*Flow switch body assembly
*
*
*
Note: Alternative pressure
vessels shown
This kit can be used to service the
pump only.
The control module is not included
and needs to be purchased
separately.

- 4 -
Cont ...
To identify which components are required, the following exploded view details the pump
components along with the serviceable parts.
Fig. 4
10
A
A
Flow switch, transfer pipe
& pressure vessel assembly
Fig. 3
20
19
17
18
27
17
21
22
15
16
14
13
28
11
9
12
1
3
5
2
4
6
8
7
17
20
19
17
21
22
17
13
28
14
16
27
Single variation pump head.
Control module not shown.
15
Note: Alternative pressure
vessel (20) shown.

- 5 -
Cont ...
To disassemble the pump, the following items are required to be removed in the sequence
detailed (Fig. 4).
• Remove screws (A) and lift complete assembly away and position next to pump ensuring no
stress is placed on the cables.
• Remove 4 screws (item 1) and gently prise off the pump body – note ‘O’-ring (item 6)
between pump body and mounting plate.
• Slide impeller away from shaft and remove woodruff key (item 7) – (see note: Fig. 5).
• Remove circlip (item 2) and mechanical seal parts. (items 3 & 4).
• Gently prise off mounting plate.
• Remove Counterface (item 5) from its mounting plate location.
• Note: Other parts are supplied in this kit and can be used as shown in Fig. 4 if replacement
required.
Note:
Difficulties may be experienced in the removal of the impeller. To overcome this, two
screwdrivers can be used to gently lever the impeller away from the shaft as detailed (Fig. 5),
ensuring equal pressure is applied to each side of the component to avoid bending the shaft.
• MAINTENANCE & CARE BEFORE REASSEMBLY
To allow ease of reassembly, along with correct functioning of the pump, the following points
on reassembly are necessary:
• All pump parts must be free from debris and assembled in the correct order.
• The impeller must be a slide fit on the shaft.
• The seal must always be replaced as a complete unit.
• SEAL IDENTIFICATION & ASSEMBLY
The seal is shown in order of identification in Fig 6.
A Seal Counterface complete with rubber cup washer.
B Rotary seal assembly.
C Stainless steel Washer.
D Seal retaining clip.
Fig. 5
NOTE: DO NOT USE EXCESSIVE
FORCE, AS THIS MAY DAMAGE THE
COMPONENTS
Fig. 6
A
B
Rotary seal assembly
Location plate
Spring
Counterface
Rubber cup washer
C
D

- 6 -
Cont ...
To assemble the seal correctly, the shaft must be clean and the following steps carried out.
1. Use End 1 of the applicator tool to push the seal counterface (item A) firmly into the
housing, ensuring it is located flat against the back of the mounting plate housing.
2. Now use End 2 of the applicator tool to push the rotary section of the seal assembly (item B)
onto the motor shaft until it is flat against the seal counterface (Fig. 7). The shaft may be
lubricated with clean water to assist assembly.
Assemble the spring and location plate onto the shaft so as to complete the rotary seal
assembly (Fig. 8)
3. The washer (item C) can then be placed on the shaft and the whole assembly held into
position by locating the Circlip (item D) in the groove and pushing it into position (Fig. 9)
WARNING: Do not install the circlip onto full shaft diameter, it must only be located in the
groove.
• REASSEMBLY
• Reassembly of the remaining pump parts is the reverse of disassembly instructions, ensuring
all re-used parts are clean, and new replacement parts fitted as required.
• Secure pump body screws to a torque of 2.6 Nm (item 1).
• Screws (A) to be tightened to 1.5 Nm of torque.
• INITIAL OPERATING INSTRUCTIONS
• Consult instruction manual for commissioning instructions.
• Do not run pump dry. Allow the water to be pumped to enter the pump body thus
ensuring the seal is lubricated before switching the pump on. Failure to do this will
damage the seal.
• Carefully check pump and pipework for leaks whilst pump running and stationary before
leaving the installation unattended.
Fig. 7 Fig. 8 Fig. 9
End 2 Applicator Tool (Item 30)
End 1
Fig. 10

- 7 -
Cont ...
SECTION 2 - CAPACITOR REPLACEMENT
The parts required to replace the capacitor are:
ITEM QTY ITEM QTY
23 Screws, Self Tapping (K40 x 16 mm) 4 26 Adhesive Foam Pad 1
24 Capacitor 1
• CAPACITOR - USED ON MONSOON UNIVERSAL PUMPS
7 µf - N1.5, N2.0, N3.0 bar Single
N1.5, N2.0 bar Twin
10 µf - N3.0 bar Twin
• DISASSEMBLY
• Isolate electrical supply before fitting replacement part.
• Replacing the capacitor, should only be carried out by a competent
person.
• The supply cord and internal wiring within the terminal box are routed
and secured to ensure compliance with the electrical standard
EN 60335-1. It is essential that prior to any disturbance of this internal
wiring, all cable routing and securing details are carefully noted to
ensure reassembly to the same factory pattern is always maintained.
Fig. 12
Capacitor
rating
24
26
23
Terminal box lid
Fig. 11

- 8 -
Cont ...
Reference Fig 11:
• Remove 4 screws (item 23), and carefully remove terminal box lid.
• IMPORTANT: Take note of capacitor wiring connection and colours before removal.
Disconnect and remove capacitor (item 24) and foam securing pad (item 26), make note of
pad fitted position.
Damaged components must be replaced. Contact Stuart Turner for
advice on replacements not supplied with kit.
• REASSEMBLY
Reassembly is the reverse of the disassembly instructions, with new replacement parts fitted
as required.
Note: For correct installation the capacitor must be connected, secured and positioned as
detailed (Figs. 13 & 14).
Secure terminal box lid screws to a torque of 0.8 Nm (item 23).
IMPORTANT NOTE: For correct pump rotation, ensure both blue wires are connected to the
linked capacitor terminals as shown.
• INITIAL OPERATING INSTRUCTIONS
• Consult instruction manual for commissiong instructions.
• Do not run pump dry. Allow the water to be pumped to enter the pump body thus ensuring
the seal is lubricated before switching the pump on. Failure to do this will damage the
seal.
• Carefully check pump and pipework for leaks whilst pump running and stationary before
leaving the installation unattended.
Receptacle at 45o
(approximately)
Fig. 13 Fig. 14
24 Receptacle at 45o
(approximately)
26

- 9 -
Cont ...
SECTION 3 - PRINTED CIRCUIT BOARD REPLACEMENT
The parts required to replace the printed circuit board are:
ITEM QTY ITEM QTY
23 Screws, Self Tapping (K40 x 16 mm) 4 26 Adhesive Foam Pad 1
25 Printed Circuit Board 1
Note: - When fitted this printed circuit board will detect the following fault conditions:
• Dry running caused by water starvation to the pump.
If the above fault condition occurs, then the pump will stop.
The fault should therefore be rectified before restarting the pump.
Check that there is sufficient water supply to the pump and also ensure that all outlets are
closed.
• Protective Logic Sequence
If water starvation occurs and the power supply to the pump remains uninterrupted, the pump
controller will perform the following protective sequence.
1) If the pump detects water starvation, it will stop operation after a 1 minute period.
2) The pump will remain in the off condition for a period of 5 minutes.
3) The pump will then re-start and if the water starvation condition remains present, the pump
will then stop operation after a 1 minute period.
4) The pump will remain in the off condition for a period of 5 minutes.
5) The pump will then re-start and if the water starvation condition remains present, the pump
will then stop operation after a 1 minute period.
6) The pump will remain in the off condition for a period of 5 minutes.
7) The pump will then re-start and if the water starvation condition remains present, the pump
will then stop operation after a 1 minute period.
8) After three consecutive resets are performed the pump will remain in the off condition
indefinitely.
9) To restart the pump, the power supply should be first isolated for a period of at least 10
seconds before switching on again.
If the pump fails to operate normally after three attempts to re-start, then please consult Stuart
Turner PumpAssist [phone].
• Fault Finding
The PCB is also fitted with a “power on” indicator light. This will remain illuminated when
mains power is supplied to the board.
The indicator light is located on the PCB within the terminal box.
This operation should only be carried out by a competent person

- 10 -
Cont ...
To view the light the following procedure must be followed:-
• Isolate the mains electrical power supply from the pump.
• Remove the four screws (item 23) retaining the terminal box lid.
• Lift the terminal box lid off.
• IMPORTANT – Ensure there is no contact with any of the internal parts of the terminal box.
• Briefly reconnect the mains power supply to the pump – the indicator light should illuminate if
the pump has been correctly wired.
• Isolate the mains electrical power supply from the pump.
• Re fit the terminal box lid ensuring no cables are trapped.
• Re fit the four terminal box lid retaining screws, tighten to 0.8 Nm.
• DISASSEMBLY
• Isolate electrical supply before fitting replacement part.
• Replacing the PCB should only be carried out by a competent person.
• The supply cord and internal wiring within the terminal box are routed
and secured to ensure compliance with the electrical standard
EN 60335-1. It is essential that prior to any disturbance of this internal
wiring, all cable routing and securing details are carefully noted to
ensure reassembly to the same factory pattern is always maintained.
Indication light
Terminal box lid
23
Fig. 15 Wiring removed for clarity
N
S1
S2 S2S3 S3
MAIN WINDING
THERMOTRIP CAPACITOR
START WINDING
FLOWSWITCH
REED (S3)
BLUE
BROWN
BLACK RED
GREEN/
YELLOW
BLUE
BROWN L
M
N
N
S2 S3 S3 S2
LE
N
FLOWSWITCH
REED (S2)
S1
S1
PRESSURE
SWITCH (S1)
230 VAC/1PH/50Hz
SUPPLY
S1
Fig. 16 Twin

- 11 -
Cont ...
Reference Fig 18.
• Remove four screws (Item 23) and carefully remove terminal box lid.
• IMPORTANT: Take note of capacitor wiring connection and colours before removal.
• Disconnect and remove capacitor, and foam securing pad (Item 26) make note of pad fitted
position.
• Remove M4 nut (Item A) then M4 lock washer (Item B) and plain washer (Item C), this
allows removal of earth wire and cup washer (Item D).
• Disconnect all wiring from terminal blocks on printed circuit board (PCB Item 25).
• Remove two M4 nuts (item A) and carefully lift PCB (Item 25) away from terminal box.
Damaged components must be replaced. Contact Stuart Turner for advice
on replacements not supplied with kit.
Fig. 18
D
Capacitor
23
26
A
C
B
A
Capacitor
25
A
MAIN WINDING
THERMOTRIP CAPACITOR
START WINDING
FLOWSWITCH
REED (S3)
BLUE
BROWN
BLACK RED
GREEN/
YELLOW
BLUE
BROWN L
M
N
N
S3 S3
LE
N
S1
S1
PRESSURE
SWITCH (S1)
S1
S2 S2S3 S3
S1
230 VAC/1PH/50Hz
SUPPLY
Fig. 17 Single

- 12 -
Cont ...
• INITIAL OPERATING INSTRUCTIONS
• Consult instruction manual for commissioning instructions.
• Do not run pump dry. Allow the water to be pumped to enter the pump body thus ensuring
the seal is lubricated before switching the pump on. Failure to do this will damage the
seal.
• Carefully check pump and pipework for leaks whilst pump running and stationary before
leaving the installation unattended.
• REASSEMBLY
Reassembly is the reverse of the disassembly instructions with the new replacement parts
fitted as required.
Note: For correct installation the capacitor must be secured and positioned as detailed in
Figs. 19 & 20.
Secure PCB nuts to a torque of 1.5 Nm (item A).
Secure terminal box lid screws to a torque of 0.8 Nm (item 23).
IMPORTANT NOTE: For correct pump rotation, ensure both blue wires are connected to the
linked capacitor terminals as shown.
Receptacles at 45o(approximately)
26
Fig. 19
Fig. 20 Receptacles at 45o(approximately)

- 13 -
Cont ...
SECTION 4 - REED SWITCH REPLACEMENT
The parts required to replace the reed switch are:
ITEM QTY ITEM QTY
23 Screws (K40 x 16 mm) 4 28 Reed Switch 1
27 Reed Switch Tie Wrap 1 29 Strain Relief Bush 3
• WIRING DIAGRAMS
N
S1
S2 S2S3 S3
MAIN WINDING
THERMOTRIP CAPACITOR
START WINDING
FLOWSWITCH
REED (S3)
BLUE
BROWN
BLACK RED
GREEN/
YELLOW
BLUE
BROWN L
M
N
N
S2 S3 S3 S2
LE
N
FLOWSWITCH
REED (S2)
S1
S1
PRESSURE
SWITCH (S1)
230 VAC/1PH/50Hz
SUPPLY
S1
Fig. 21 Twin
• DISASSEMBLY
• Isolate electrical supply before fitting replacement part.
• Replacing the reed switch components should only be carried out by a
competent person.
• The supply cord and internal wiring within the terminal box are routed
and secured to ensure compliance with the electrical standard
EN 60335-1. It is essential that prior to any disturbance of this internal
wiring, all cable routing and securing details are carefully noted to
ensure reassembly to the same factory pattern is always maintained.
• Remove four screws and carefully remove terminal box lid (item 23).
• Note the cable routing within the terminal box (Figs. 21 & 22).
• Slacken the two screws retaining the reed switch wires on the PCB.
• Remove the strain relief bush and reed switch cable by gripping with pliers (Fig. 23) and
pulling downwards from the terminal box.
• Remove the existing reed switch by cutting the securing tie wrap and pulling away from
the flow switch body (Fig. 23)
MAIN WINDING
THERMOTRIP CAPACITOR
START WINDING
FLOWSWITCH
REED (S3)
BLUE
BROWN
BLACK RED
GREEN/
YELLOW
BLUE
BROWN L
M
N
N
S3 S3
LE
N
S1
S1
PRESSURE
SWITCH (S1)
S1
S2 S2S3 S3
S1
230 VAC/1PH/50Hz
SUPPLY
Fig. 22 Single

- 14 -
Cont ...
Damaged components must be replaced. Contact Stuart Turner for advice on
replacements not supplied with kit.
• REASSEMBLY
• Fit the new strain relief bush around the reed switch cable and squeeze the strain relief bush
with pliers to compress the cable.
• Push the cable and bush into the base of the terminal box ensuring the bush is fully seated
into its location.
• Connect the two reed switch wires to the PCB (Figs. 21 & 22)
• For correct operation of the flow switch, the reed must be secured to the body (Fig. 25)
• Firstly feed the tie wrap (item 13) through the retainer on the reed switch, ensuring that the tie
wrap serrations are facing outwards (Fig. 24).
23
Terminal
box lid
Bush
Pliers
Terminal box
base
Cut tie wrap
Fig. 23
Fig. 24
28
Catch
Retainer
Serrations
27

- 15 -
Cont ...
• Locate the reed switch within the body groove as highlighted X-X (Fig. 25), and feed the tie
wrap through the second catch.
• The tie wrap can now be pulled tight to secure the reed and excess cut to length as shown
(Fig. 26)
• INITIAL OPERATING INSTRUCTIONS
• Consult instruction manual for commissioning instructions.
• Do not run pump dry. Allow the water to be pumped to enter the pump body thus ensuring
the seal is lubricated before switching the pump on. Failure to do this will damage the seal.
• Carefully check pump and pipework for leaks whilst pump running and stationary before
leaving the installation unattended.
X
X
Fig. 25 Fig. 26

- 16 -
Cont ...
SECTION 5 - PRESSURE SWITCH REPLACEMENT
The parts required to replace the pressure switch are:
ITEM QTY ITEM QTY
19 Rubber Washer (G ½ ") 1 22 Pressure Switch 1
21 Bonded Seal 1 23 Screws, Self Tapping (K40 x 16 mm) 4
• PRESSURE SWITCHES
Number Used on Monsoon Negative Pumps
19784 N1.5 / N2.0 bar Twins
19785 N2.0 / N3.0 bar Twins, N2.0 / N3.0 bar Single
• WIRING DIAGRAMS
N
S1
S2 S2S3 S3
MAIN WINDING
THERMOTRIP CAPACITOR
START WINDING
FLOWSWITCH
REED (S3)
BLUE
BROWN
BLACK RED
GREEN/
YELLOW
BLUE
BROWN L
M
N
N
S2 S3 S3 S2
LE
N
FLOWSWITCH
REED (S2)
S1
S1
PRESSURE
SWITCH (S1)
230 VAC/1PH/50Hz
SUPPLY
S1
Fig. 28 Twin
Part number
location
Fig. 27
MAIN WINDING
THERMOTRIP CAPACITOR
START WINDING
FLOWSWITCH
REED (S3)
BLUE
BROWN
BLACK RED
GREEN/
YELLOW
BLUE
BROWN L
M
N
N
S3 S3
LE
N
S1
S1
PRESSURE
SWITCH (S1)
S1
S2 S2S3 S3
S1
230 VAC/1PH/50Hz
SUPPLY
Fig. 29 Single

- 17 -
Cont ...
• DISASSEMBLY
• Isolate electrical supply before fitting replacement part.
• Replacing the pressure switch components should only be carried out
by a competent person.
• The supply cord and internal wiring within the terminal box are routed
and secured to ensure compliance with the electrical standard
EN 60335-1. It is essential that prior to any disturbance of this internal
wiring, all cable routing and securing details are carefully noted to
ensure reassembly to the same factory pattern is always maintained.
Note:
The switch supplied with this kit may appear different to the unit being replaced. The variation
is due to product evolution and is intentional.
• Unscrew pressure vessel and remove rubber washer.
• Remove four screws (item 23) and carefully remove terminal box lid (Fig. 30).
• Note the cable routing within the terminal box (Figs. 28, 29).
• Identify and remove the pressure switch wiring from the terminal block on PCB.
• IMPORTANT: Take note of cable clamp position before removal as reassembly in the
original factory orientation is essential - Remove two screws and cable clamp, this allows
the pressure switch cables to be removed from the terminal box (Figs. 28, 29).
• Remove the strain relief bush and reed switch cable by gripping with pliers (Fig. 30) and
pulling downwards from the terminal box.
• Remove the existing reed switch by cutting the securing tie wrap and pulling away from
the flow switch body (Fig. 30)
23
Terminal
box lid
Bush
Pliers
Terminal box
base
Cut tie wrap
Fig. 30

- 18 -
Cont ...
• Remove the pressure switch cable from the terminal box by gently sliding the cable out
through the sealing grommet, ensuring no damage to the seal area (Fig. 31).
• Unscrew the pressure switch and seal from the flow switch manifold body (Fig 31).
Damaged components must be replaced. Contact Stuart Turner for advice
on replacements not supplied with kit.
• REASSEMBLY
Reassembly is the reverse of the disassembly instructions with the new replacement parts
fitted as required.
• Pressure switch (item 22) to be tightened to a torque of 7-8 Nm.
• Secure two cable clamp screws (item 23) and four terminal box lid screws, to a torque of
0.8 Nm (Fig. 31).
• INITIAL OPERATING INSTRUCTIONS
• Consult instruction manual for commissioning instructions.
• Do not run pump dry. Allow the water to be pumped to enter the pump body thus ensuring
the seal is lubricated before switching the pump on. Failure to do this will damage the
seal.
• Carefully check pump and pipework for leaks whilst pump running and stationary before
leaving the installation unattended.
Fig. 31
Flow switch
manifold body
21
22

- 19 -
Cont ...
SECTION 6 - NON-RETURN VALVE (NRV) REPLACEMENT
The parts required to replace the non-return valve are:
ITEM QTY ITEM QTY
9 ‘O’-Ring (ID 24.6 mm x 2.4 mm sec) 4 11 Non-Return Valve Assembly (NRV) 2
10 Non-Return Valve Holder 2 14 Screws (M4 x 16 mm) 4
• DISASSEMBLY
To access the NRV, the flow switch body assemblies must first be removed (Fig. 32).
Please refer to the following, dependant on pump.
Note: The NRV is part of the flow switch body assemblies - see Figs. 33 & 34 for reference.
Flow Switch Assemblies:-
• Remove screws (item 14) and lift complete assembly away ensuring no stress is placed on
the cables.
*Flow switch body assembly
Fig. 32
*
*
Fig. 33
14
Flow switch manifold
assembly
Manifold clamp
Pump body
*
Single Twin

- 20 -
Cont ...
Once the flow switch assemblies have been removed the NRV is now accessible as shown in
Fig. 33.
• Remove ‘O’-ring (item 9) from between pump body and flow switch assembly.
• Firmly pull the NRV assembly (items 10/11) from the lower end of the flow switch body
assembly (Fig. 34).
• Remove ‘O’-ring (item 12).
• REASSEMBLY
Reassembly is reverse of disassembly instructions, ensuring all re-used parts are clean, and
new replacement parts fitted as required.
Secure flow switch manifold clamp screws to a torque of 1.5 Nm (item 9).
• INITIAL OPERATING INSTRUCTIONS
• Consult instruction manual for commissioning instructions.
• Do not run pump dry. Allow the water to be pumped to enter the pump body thus ensuring
the seal is lubricated before switching the pump on. Failure to do this will damage the
seal.
• Carefully check pump and pipework for leaks whilst pump running and stationary before
leaving the installation unattended.
Fig. 34
Flow switch body
11
9
10
12