KNF NF 1.25 Series, NF 1.25 DCB-B, NF 1.25 DC, NF 1.25 DCB-4B Operating And Installation Instructions
KNF Flodos AG BA_NF1.25_EN_03_163242
Translation of Original Operating and Installation Instructions, English Keep for future reference!
DIAPHRAGM LIQUID PUMP
NF 1.25
Operating and
Installation
Instructions
Read and observe these Operating and Installation Instructions!
An additional letter prefixing
the NF model code is a country-specific designation, with no
technical relevance.
Contents Page
1. About this document ................................................................. 2
2. Use ........................................................................................... 3
3. Safety ....................................................................................... 4
4. Technical data .......................................................................... 6
5. Assembly and function ............................................................. 9
6. Installation and connection ..................................................... 10
7. Operation ................................................................................ 13
8. Servicing ................................................................................. 16
9. Troubleshooting ...................................................................... 18
10. Decontamination declaration .................................................. 20
KNF Flodos AG
Wassermatte 2
6210 Sursee, Switzerland
Tel. +41 (0)41 925 00 25
Fax +41 (0)41 925 00 35
www.knf-flodos.ch
info@knf-flodos.ch
NF 1.25 RP DC 12V
DC / DCB-B / DCB-4B
RP / RT [Ch. 4]
NF / UNF
Supply voltage [Ch. 4]
1.25
- / PMLxxxx / PLxxxx [Ch. 1]
Diaphragm liquid pump NF 1.25 About this document
KNF Flodos AG BA_NF1.25_EN_03_163242
Translation of Original Operating and Installation Instructions, English 2
1. About this document
1.1. Use of the Operating and Installation Instructions
The Operating and Installation Instructions are part of the pump.
➔ Forward the Operating and Installation Instructions to any
subsequent owners of the pump.
Customer-specific project pumps (pump models which begin with
"PL" or "PML") may differ from the Operating and Installation
Instructions.
➔ In the case of project pumps, take note of any additionally
agreed specifications.
1.2. Symbols and markings
Warning
WARNING
This symbol indicates a potential danger.
It also indicates the possible consequences of failure
to observe the warning. The signal word (e.g. "Warning") indicates the level of danger.
➔ Here you will see actions for avoiding the danger
and potential consequences.
Danger levels
Signal word
Meaning
Consequences if not observed
DANGER
warns of immediate danger
Consequences include death or
serious injuries and/or serious
property damage
WARNING
warns of potential
danger
Death or serious injuries and/or
serious property damage are
possible
CAUTION
warns of a potentially dangerous
situation
Minor injuries or damage to
property are possible
Tab. 1
Other information and symbols
➔ This indicates an activity (step) that must be carried out.
This indicates the first step of an activity to be carried out. Any
additional steps required are numbered consecutively.
This symbol indicates important information.
Project pumps
Diaphragm liquid pump NF 1.25 Use
KNF Flodos AG BA_NF1.25_EN_03_163242
Translation of Original Operating and Installation Instructions, English 3
2. Use
2.1. Intended use
The pumps are intended for transferring and metering liquids.
Owner's responsibility
Only install and operate the pumps under the operating parameters
and conditions described in Chapter 4, Technical data.
Only complete pumps may be taken into service.
Before transferring or metering a medium, check whether the
medium can be transferred danger-free in the specific application
case.
Before using a medium, check the compatibility of the materials of
the pump head, pump housing, diaphragm and valves with the
medium.
The temperature of the medium must lie within the permissible
temperature range (see Chapter 4).
The pumped medium should not contain particles as these can
prevent the pump from working correctly. If this cannot be ensured,
a < 50 m filter with a sufficiently large filter area must be used
upstream of the pump.
2.2. Improper use
The pumps must not be operated in an explosive atmosphere.
For special modifications outside the standard technical specifications, please contact your KNF technical adviser.
Operating parameters and
conditions
Requirements for
transferred medium
Diaphragm liquid pump NF 1.25 Safety
KNF Flodos AG BA_NF1.25_EN_03_163242
Translation of Original Operating and Installation Instructions, English 4
3. Safety
Observe the safety precautions in Chapters
6. Installation and connection, and 7. Operation.
The pumps are built according to the generally recognised rules of
technology and in accordance with the pertinent occupational
safety and accident prevention regulations. Nevertheless, dangers
can result during their use which lead to injuries to the user or
others, or to damage to the pump or other property.
Only use the pumps when they are in a good technical and proper
working order, in accordance with their intended use, observing the
safety advice within the Operating and Installation Instructions, at
all times.
Make sure that only trained and instructed personnel or specially
trained personnel work on the pumps. This especially applies to
assembly, connection and servicing work.
Make sure that all personnel have read and understood the Operating and Installation Instructions, and in particular the "Safety"
chapter.
Always ensure adherence to all pertinent accident prevention and
safety regulations when working on and operating the pump.
When transferring dangerous media, observe the safety regulations for handling such media.
Always ensure adherence to all information stickers on the pumps,
such as flow direction arrows and type plates, and keep stickers in
legible condition.
All replacement parts should be properly stored and disposed of in
accordance with the applicable environmental protection regulations. Ensure adherence to the pertinent national and international
regulations. This especially applies to parts contaminated with toxic
substances.
Dispose of all packaging in an environmentally-appropriate
manner. The packaging materials are recyclable.
Ensure that the old appliance is disposed of in an environmentally-appropriate manner. Use appropriate waste
collection systems for the disposal of end-of-life equipment. Used pumps contain valuable recyclable materials.
Personnel
Working in a
safety-conscious manner
Handling dangerous media
Notes
Environmental protection
Disposal
Diaphragm liquid pump NF 1.25 Safety
KNF Flodos AG BA_NF1.25_EN_03_163242
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The pumps are in accordance with the requirements of the guidelines 2011/65/EU (ROHS2)
The pumps conform to the safety requirements regarding electromagnetic compatibility in EC Directive 2004/108/EC.
For the purposes of the Machinery Directive 2006/42/EC, pumps
are “partly completed machinery", and are therefore to be regarded
as not ready for use. Partly completed machinery may not be
commissioned until such time as it has been determined that the
machine in which the partly completed machinery is to be assembled conforms to the provisions of the Machinery Directive
2006/42/EC. The essential requirements of Annex I of Directive
2006/42/EC (general principles) are applied and observed.
The following harmonised standards are met:
NF 1.25 DC
▪ EN 55014
NF 1.25 DCB-B / DCB-4B
▪ IEC/EN 61000-6-2
▪ IEC/EN 61000-6-3
All repairs to the pump(s) must be carried out by the relevant KNF
Customer Service team.
Only use genuine parts from KNF for servicing work.
EU directives/standards
Customer services and
repairs
Diaphragm liquid pump NF 1.25 Technical data
KNF Flodos AG BA_NF1.25_EN_03_163242
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4. Technical data
Pump materials
The pump type RP stands for:
Assembly
Material1)
Pump head*
PPS
Anchor valves / seals
EPDM
Diaphragm
EPDM
Resonating diaphragm
EPDM
Tab. 2 1) according to DIN ISO 1629 and 1043.1
* Pump head (Fig. 1) comprises an intermediate plate and a connecting
plate
The pump type RT stands for:
Assembly
Material1)
Pump head*
PPS
Anchor valves / seals
FFKM
Diaphragm
PTFE-coated
Resonating diaphragm
FFKM
Tab. 3 1) according to DIN ISO 1629 and 1043.1
* Pump head (Fig. 1) comprises an intermediate plate and a connecting
plate
Hydraulic ratings
Parameter
Value
Flow rate DC [ml/min]
1), 2)
300
Flow rate DCB-B [ml/min]
1), 2)
300
Flow rate DCB-4B [ml/min]
1), 2)
50-300
Permissible pressure [bar g]
6
Permissible pressure (with restricted operating time) [bar g]
10
Suction head [mWG]
3
Tab. 4
1) Measured with water at 20°C / at atmospheric pressure
2) Flow rates may vary from the values shown, depending on fluid viscosi-
ty, pump head material and the hoses / hose connectors used.
Hydraulic connections
Parameter
Value
Hose connection NF1.25 ID / OD [mm]
4 / 6
Hose connection UNF1.25 ID / OD [Inch]
1/8" / 1/4"
Tab. 5
Diaphragm liquid pump NF 1.25 Technical data
KNF Flodos AG BA_NF1.25_EN_03_163242
Translation of Original Operating and Installation Instructions, English 7
Specifications NF 1.25 DC
Motor voltage
12V
24V
Power consumption [W]
4.9
4.9
Max. I load [A]
0.41
0.20
Protection class [-]
IP00
Weight [g]
157
Tab. 6
Specifications NF 1.25 DCB-4B
Motor voltage
DCB-B
DCB-B
DCB-4B
Supply voltage [V]
12
24
10..26.4
Power consumption [W]
5.8
6.2
7.0
Max. I load [A]
0.48
0.26
0.53..0.25
Protection class [-]
IP50
Weight [g]
185
Tab. 7
Electrical specifications for motor DCB-4B
Electrical connections
Lead assignment
Function
Wire colour
Signal
name
Size
+ Supply voltage
red
+ Vs
AWG 24
- Supply voltage
black
- Vs / GND
AWG 24
Speed control – input
signal
white
Vctrl
AWG 24
Frequency output –
output signal
green
FG
AWG 24
DC control input Vctrl
Control voltage range DC
[VDC]
0..10
Speed range
[rpm]
250..4500
Resistant to surge voltages
[VDC]
± 30
Input resistance (Vctrl ≤ 11.1VDC)
[k]
102
Threshold voltage
[VDC]
0.19
Control voltage characteristic
Diaphragm liquid pump NF 1.25 Technical data
KNF Flodos AG BA_NF1.25_EN_03_163242
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FG frequency output
FG pulses per mech. revolution
[ ] 6 Pulse length "low"
[%]
50
Output series resistance
[k]
2.2
Output level 'high'
[V]
≥ 2.8
Output level 'low'
[V]
≤ 0.5
Tab. 8
In the case of type NF 1.25 DCB-4B the supply voltage is not
designed for operation with pulse-width modulated voltages
(PWM).
It is permissible to actuate the control voltage with a PWM
signal (frequency: 1 … 20kHz).
Electrostatic sensitive components (ESD)
Other parameters
Parameter
Value
Permissible
ambient temperature range [°C]
+ 5 to + 40
Permissible media temperature range [°C]
+ 5 to + 80
Permissible kinematic viscosity of medium
[cSt]
≤ 150
Tab. 9
Diaphragm liquid pump NF 1.25 Assembly and function
KNF Flodos AG BA_NF1.25_EN_03_163242
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5. Assembly and function
Basic elements
1 Outlet
2 Inlet
3 Connecting plate
4 Drive
5 Connecting leads
6 Head plate
7 Intermediate plate
Fig. 1: Diaphragm liquid pump NF1.25
1 Outlet valve
2 Inlet valve
3 Working chamber
4 Diaphragm
5 Eccentric
6 Connecting rod
7 Pump drive
Fig. 2: Pump assembly
Diaphragm liquid pumps are based on reciprocating displacement
pump technology. The elastic diaphragm (4) is moved up and
down by the eccentric (5) and the connecting rod (6). In the downward stroke it aspirates the medium to be transferred via the inlet
valve (2). In the upward stroke, the diaphragm pushes the medium
out of the pump head via the outlet valve (1). The diaphragm
hermetically seals off the working chamber (3) from the pump drive
(7).
Diaphragm liquid pump NF 1.25 Installation and connection
KNF Flodos AG BA_NF1.25_EN_03_163242
Translation of Original Operating and Installation Instructions, English 10
6. Installation and connection
Only install the pumps under the operating parameters and conditions described in Chapter 4, Technical data.
Observe the safety precautions (see Chapter 3).
6.1. Installation
➔ Before installation, store the pump at the installation location to
bring it up to ambient temperature.
➔ Mounting dimensions (see Fig. 3 to 5)
Fig. 3: Mounting dimensions NF 1.25 DC
Fig. 4: Mounting dimensions NF 1.25 DCB-B
Mounting dimensions
Diaphragm liquid pump NF 1.25 Installation and connection
KNF Flodos AG BA_NF1.25_EN_03_163242
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Fig. 5: Mounting dimensions NF 1.25 DCB-4B
➔ Make sure that the installation location is dry and the pump is
protected against water in the form of rain, spray, splashes and
drips.
➔ Protect the pump against dust.
➔ Protect the pump against vibration and impact.
➔ Generally speaking, the pump can be mounted in any installa-
tion position. For maximum precision and rapid venting, install
pump as shown in the illustration (Fig. 5).
6.2. Electrical connection
➔ Only have the pump connected by an authorized specialist.
➔ Only have the pump connected when the power supply is
disconnected.
➔ When connecting the device to a power source, the relevant
norms, directives, regulations and technical standards must be
observed.
Connecting the pump
Make sure that the power supply data match the data on the
motor's type plate. The current consumption can be found on
the type plate.
Connect the motor cables. For electrical data see Chapter 4.
Installation location
Installation position
Fig. 6: Optimal mounting
orientation
Diaphragm liquid pump NF 1.25 Installation and connection
KNF Flodos AG BA_NF1.25_EN_03_163242
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Note the proper polarity.
For DC motors:
red motor cable: +
black motor cable: -
In the case of brushless DC motors:
incorrect polarity may damage the electronics!
6.3. Hydraulic connection
➔ Only connect components to the pump that are designed to
handle the hydraulic data of the pump (see
Chapter 4, Technical data).
➔ Only use hoses that are suitable for the maximum operating
pressure of the pump (see Chapter 4).
➔ Only use hoses that are sufficiently chemically resistant to the
liquids being pumped.
6.3.1. Connecting the pump
Arrows on the pump head indicate the flow direction.
Remove the protective caps from the connections.
Connect the suction and pressure lines.
Keep the suction line as short as possible in order to keep the
priming process as brief as possible.
If the pump is used to build up pressure, make sure that all
transition joints between hose and pump are secure in order to
ensure that the hoses cannot come off.
Check that the hoses and transition joints are fitted correctly
and securely.
Check that the system is leak-tight.
Connected
components
Hoses
Diaphragm liquid pump NF 1.25 Operation
KNF Flodos AG BA_NF1.25_EN_03_163242
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7. Operation
➔ Operate the pumps only under the operating parameters and
conditions described in Chapter 4, Technical data.
➔ Make sure the pumps are being used properly (see Chapter
2.1).
➔ Avoid improper use of the pumps (see Chapter 2.2).
➔ Observe the safety precautions (see Chapter 3).
➔ The pumps are components that are intended to be incorpo-
rated into another machine. Before putting them into service it
must be established that the machinery or equipment in which
they are installed meet the relevant regulations.
CAUTION
Risk of burning
The drive heats up.
➔ Avoid contact with the pump drive.
➔ Avoid contact with flammable materials.
Excessive pressure and the inherent dangers thereof can be
prevented by placing a bypass line with a pressure relief valve
between the pressure and suction side of the pump. For
further information, contact your KNF technical adviser (telephone number: see first page).
➔ If the pump stops running, restore the system to normal at-
mospheric pressure.
For pumps with thermal switch or electronic overload protection:
WARNING
Risk of physical injury and damage to the pump due
to automatic start
If the pump overheats and pump operation is
stopped by the thermal switch / electronics, the
pumps will restart automatically as soon as they have
had time to cool down.
➔ Take steps to ensure that this cannot produce a
hazardous situation.
Switching the pumps on and off
The motor speed of the pump, and thus the flow rate, is adjustable
and can also be regulated to some extent.
For more details, see Chapter 4, Technical data
Duty cycle / short cycle operation
KNF pumps are designed for continuous operation.
Short start and stop cycles may adversely affect the service life of
the brushed motors.
If the pump is operated with short cycles in your application,
please contact your KNF technical adviser for further information (Telephone number: see first page).
Pump standstill
Setting and regulating motor
speed
Impulse operation
Diaphragm liquid pump NF 1.25 Operation
KNF Flodos AG BA_NF1.25_EN_03_163242
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Switching on the pump
➔ In order to guarantee that the pump can start every time it is
advisable to reduce the back pressure to an acceptable level. If
you experience a brief power interruption, check for the presence of pressure or vacuum before restarting.
For more specific information contact your KNF technical
adviser.
Switching off the pump
➔ KNF recommends: If transferring aggressive liquids, the pump
should be flushed thoroughly prior to switch off (see Chapter
8.2.1), as this will help to lengthen the service life of the diaphragm.
➔ Restore the system to normal atmospheric pressure (release
hydraulic pressure in pump).
NF1.25 flow rate
Fig. 7: Flow rate of the pump NF 1.25 DC
Fig. 8: Flow rate of the pump NF 1.25 DCB-B / DCB-4B
Diaphragm liquid pump NF 1.25 Operation
KNF Flodos AG BA_NF1.25_EN_03_163242
Translation of Original Operating and Installation Instructions, English 15
Fig. 9: Flow rate of pump NF 1.25 DCB-4B, depending on control voltage
Diaphragm liquid pump NF 1.25 Servicing
KNF Flodos AG BA_NF1.25_EN_03_163242
Translation of Original Operating and Installation Instructions, English 16
8. Servicing
8.1. Servicing schedule
Component
Servicing interval
Pump
- Regular inspection for external
damage or leaks
Pump head
- Clean if the flow rate decreases, the
pump does not work or no vacuum
is created (Chapter 8.2)
Diaphragm, anchor
valves and seals
- Change as soon as pumping capac-
ity decreases, preferably sooner
Tab. 10
8.2. Cleaning
WARNING
Health hazard due to dangerous
substances in the pump
Depending on the substance transferred, caustic
burns or poisoning are possible.
➔ Wear protective clothing if necessary, e.g. pro-
tective gloves.
➔ Flush the pump with a neutral liquid and pump
empty.
8.2.1. Flushing the pump
➔ If transferring aggressive media, KNF recommends flushing
the pump with a neutral fluid under atmospheric conditions for
a few minutes before switching off, to extend the service life of
valves and diaphragm.
8.2.2. Cleaning the pump
➔ Where possible, wipe the components with a dry cloth. Do not
use cleaning solvents as these may corrode plastic parts.
➔ If there is compressed air available, blow off components.
▪ Pump or drive disconnected from the mains and de-
energized.
▪ The pump must be free of any hazardous substances
▪ Hoses must be disconnected from the pump head
▪ We recommend replacing the diaphragm when the head
parts are removed.
Qty.
Tool
1
T6 Torx screwdriver
Tab. 11
Information on procedure
Prior requirements
Tool
Diaphragm liquid pump NF 1.25 Servicing
KNF Flodos AG BA_NF1.25_EN_03_163242
Translation of Original Operating and Installation Instructions, English 17
Disassemble pump head
Undo the four head screws (1) using a Torx screwdriver T6
Remove the resonating diaphragm (3) from the connecting
plate (4).
Disassemble pump head
Remove both anchor valves (7) from the intermediate plate (9)
and the connecting plate (4)
Remove the two anchor valve seals (6) from the intermediate
plate (9)
Undo the diaphragm (10) by means of the head plate (2). Make
sure that no washers (11) fall into the housing.
We recommend replacing the diaphragm (10).
Cleaning the parts
Clean the anchor valves (7), the anchor valve seals (6) and the
diaphragm (10) with a cloth and then blow off with compressed
air.
Blow off the intermediate plate (9), connecting plate (4) and
head plate (2) with compressed air
Mounting the diaphragm
Screw diaphragm (10) with washer (11) into connecting rod
and tighten firmly. Make sure that no washers (8) fall into the
pump housing.
Use the head plate (2) to carefully tighten the diaphragm.
Mounting the valves and seals
Insert the seals (6) in the connecting plate (4).
Insert the anchor valves (7) in the intermediate plate (9) and
the connecting plate (4).
Mounting the pump head
Insert the intermediate plate (9).
ATTENTION: Make sure that the orientation is correct so that
the connections point in the right direction!
A pin and hole system prevents incorrect assembly.
Place the connecting plate (4) on top of the intermediate plate
(9)
Place head plate (2) on connecting plate (4) and secure using
the 4 head screws (1)
8.3. Replacing diaphragms, valves and seals
Same procedure as in Chapter 8.2, "Cleaning", except that instead
of cleaning the diaphragm (10), anchor valves (7) and seals (6),
these components must be replaced.
Fig. 10
1 Head screws
2 Head plate
3 Resonating diaphragm
4 Connecting plate
5 Clamp ring
6 Anchor valve seal
7 Anchor valve
8 Union nut
9 Intermediate plate
10 Diaphragm
11 Washer
Diaphragm liquid pump NF 1.25 Troubleshooting
KNF Flodos AG BA_NF1.25_EN_03_163242
Translation of Original Operating and Installation Instructions, English 18
9. Troubleshooting
➔ Disconnect the pump power supply before working on the
pump.
➔ Make sure that the pump is de-energised.
Pump does not work
Cause
Fault remedy
Pump not connected to mains
power supply
➔ Connect pump to mains supply
Power supply is not switched on
➔ Switch on power supply
Connections or hoses are
blocked
➔ Check connections and hoses
➔ Remove blockage
External valve is closed or filter
is clogged.
➔ Check external valves and filters
Diaphragm, anchor valves or
seals are worn.
➔ Replace diaphragm, anchor valves and seals
(see Chapter 8.3).
Tab. 12
Pump is not priming
Cause
Fault remedy
Suction side of pump not connected
➔ Connect the suction side of the pump
Liquid in the priming container is
too low
➔ Fill priming container
Hose connections are not leaktight
➔ Secure transition joints between hose and connections with
clamps or other clamping elements
System valve is closed or filter
is clogged
➔ Open system valve
➔ Clean filter
Pump head is filled with gas:
the system is unable to handle
the pressure on the pressure
side
➔ Reduce pressure at pressure side
Particles in the pump
➔ Clean the pump head (see Chapter 8.2)
The pump parts are not resistant to the medium to be
pumped
➔ Replace the pump head with a compatible version
Incorrect interchange of pressure and suction line connections
➔ Remove pressure and suction lines and re-connect correctly
Tab. 13
Diaphragm liquid pump NF 1.25 Troubleshooting
KNF Flodos AG BA_NF1.25_EN_03_163242
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Flow rate, suction head or pressure head is too low
The pump does not achieve the performance stated in the technical data or on the data sheet.
Cause
Fault remedy
Components in the system
connected to the suction and
pressure sides, such as hoses,
valves or filters, are causing too
much resistance
➔ Modify installation, check cross-sections of components
Hose connections are not leaktight
➔ Secure transition joints between hose and hose connectors
with clamps or other clamping elements
Particles in the pump
➔ Clean the pump head, install suction-side filter if required
(see Chapter 8.2).
Viscosity of the transferred
medium is too high
➔ Contact KNF
Incorrect interchange of pressure and suction line connections
➔ Remove pressure and suction lines and re-connect correctly
The pump parts are not resistant to the medium to be
pumped
➔ Replace the pump head with a compatible version
Tab. 14
Fault cannot be rectified
If you are unable to identify any of the above causes, please send the pump to KNF customer services
(see address on last page).
Flush the pump to clear the pump head of any hazardous or
aggressive fluids (see Chapter 8.2.1).
Dismantle the pump.
Clean the pump (see Chapter 8.2.2).
Send the pump to KNF customer services along with the
completed decontamination declaration (see Chapter 10).
Please indicate the medium that the pump is used to transfer.
Diaphragm liquid pump NF 1.25 Decontamination declaration
KNF Flodos AG BA_NF1.25_EN_03_163242
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10. Decontamination declaration
KNF shall only undertake to repair the pump on condition that
the customer provides certification of the transferred media
and the cleaning of the pump (decontamination declaration).
➔ In order to send a product back use the decontamination
declaration, which either was delivered with the product or is
available on www.knf.com (Downloads).
Please fill in the pump type, serial number, pumped media and all
other required information. Send the signed form together with the
product to your KNF representative.
Diaphragm liquid pump NF 1.25 For your notes
KNF Flodos AG BA_NF1.25_EN_03_163242
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Diaphragm liquid pump NF 1.25 For your notes
KNF Flodos AG BA_NF1.25_EN_03_163242
Translation of Original Operating and Installation Instructions, English 22
Diaphragm liquid pump NF 1.25 For your notes
KNF Flodos AG BA_NF1.25_EN_03_163242
Translation of Original Operating and Installation Instructions, English 23
KNF worldwide
Please find your local KNF partners at: www.knf.com
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