Nordson A20A User manual

A20A Automatic Electric
Airless Spray Gun
Customer Product Manual
Part 108182-03
Issued 03/17
NORDSON CORPORATION •AMHERST, OHIO •USA
C
APPROVED
US
FM
For parts and technical support, call the Industrial Coating
Systems Customer Support Center at [phone] or
contact your local Nordson representative.
This document is subject to change without notice.
Check http://emanuals.nordson.com for the latest version.

Part 108182-03 E2017 Nordson Corporation
Table of Contents
Safety 1.......................................
Qualified Personnel 1.........................
Intended Use 1..............................
Regulations and Approvals 1..................
Personal Safety 2............................
High-Pressure Fluids 2.....................
Fire Safety 3................................
Halogenated Hydrocarbon Solvent Hazards 4.
Action in the Event of a Malfunction 4...........
Disposal 4..................................
Safety Labels 5..............................
Description 6..................................
Features 6...................................
Models 6...................................
Specifications 7...............................
Ratings and Label Information 7...............
Installation 8..................................
Mounting 8..................................
Fluid Connections 8..........................
Electrical Connections 8.......................
Baseefa Special Conditions
for Safe Use 9...............................
Spray Monitor System Installation 9.............
Transducer Installation 9....................
CO-Plate Installation 9......................
CO-Plate Selection 10.......................
Operation 11...................................
Maintenance 11................................
Troubleshooting 12.............................
Repair 13......................................
Ball and Seat Module Replacement 13...........
Removal 13................................
Installation 13..............................
Solenoid Coil Replacement 14..................
Armature Replacement 15.....................
Parts 17.......................................
Gun Models 17...............................
Service Kits 17...............................
Standard Short and Extended A20A Spray Guns 18
CE/ATEX Short and Extended A20A Spray Guns 20
8-Inch Extended Standard A20A Spray Gun 22...
Service Kits 24...............................
Ball and Seat Kit 24.........................
Standard Coil Kit 24........................
CE/ATEX Approved Coil Kit 24...............
Armature Kits 25...........................
Buna-N Soft Goods Kit 25...................
EPR Soft Goods Kit 25......................
Contact Us
Nordson Corporation welcomes requests for information, comments, and
inquiries about its products. General information about Nordson can be
found on the Internet using the following address:
http://www.nordson.com.
Address all correspondence to:
Nordson Corporation
Attn: Customer Service
555 Jackson Street
Amherst, OH 44001
Notice
This is a Nordson Corporation publication which is protected by copyright.
Original copyright date 1999. No part of this document may be
photocopied, reproduced, or translated to another language without the
prior written consent of Nordson Corporation. The information contained
in this publication is subject to change without notice.
Trademarks
CanWorks, CleanSleeve, Nordson, and the Nordson logo are registered
trademarks of Nordson Corporation.
All other trademarks are the property of their respective owners.

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A20A Automatic Electric Airless Spray Gun
Safety
Read and follow these safety instructions. Task- and equipment-specific
warnings, cautions, and instructions are included in equipment
documentation where appropriate.
Make sure all equipment documentation, including these instructions, is
accessible to persons operating or servicing equipment.
Qualified Personnel
Equipment owners are responsible for making sure that Nordson equipment
is installed, operated, and serviced by qualified personnel. Qualified
personnel are those employees or contractors who are trained to safely
perform their assigned tasks. They are familiar with all relevant safety rules
and regulations and are physically capable of performing their assigned
tasks.
Intended Use
Use of Nordson equipment in ways other than those described in the
documentation supplied with the equipment may result in injury to persons
or damage to property.
Some examples of unintended use of equipment include
Susing incompatible materials
Smaking unauthorized modifications
Sremoving or bypassing safety guards or interlocks
Susing incompatible or damaged parts
Susing unapproved auxiliary equipment
Soperating equipment in excess of maximum ratings
Regulations and Approvals
Make sure all equipment is rated and approved for the environment in which
it is used. Any approvals obtained for Nordson equipment will be voided if
instructions for installation, operation, and service are not followed.

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Personal Safety
To prevent injury follow these instructions.
SDo not operate or service equipment unless you are qualified.
SDo not operate equipment unless safety guards, doors, or covers are
intact and automatic interlocks are operating properly. Do not bypass or
disarm any safety devices.
SKeep clear of moving equipment. Before adjusting or servicing moving
equipment, shut off the power supply and wait until the equipment
comes to a complete stop. Lock out power and secure the equipment to
prevent unexpected movement.
SRelieve (bleed off) hydraulic and pneumatic pressure before adjusting or
servicing pressurized systems or components. Disconnect, lock out,
and tag switches before servicing electrical equipment.
SWhile operating manual spray guns, make sure you are grounded.
Wear electrically conductive gloves or a grounding strap connected to
the gun handle or other true earth ground. Do not wear or carry metallic
objects such as jewelry or tools.
SIf you receive even a slight electrical shock, shut down all electrical or
electrostatic equipment immediately. Do not restart the equipment until
the problem has been identified and corrected.
SObtain and read Material Safety Data Sheets (MSDS) for all materials
used. Follow the manufacturer’s instructions for safe handling and use
of materials, and use recommended personal protection devices.
SMake sure the spray area is adequately ventilated.
STo prevent injury, be aware of less-obvious dangers in the workplace
that often cannot be completely eliminated, such as hot surfaces, sharp
edges, energized electrical circuits, and moving parts that cannot be
enclosed or otherwise guarded for practical reasons.
High-Pressure Fluids
High-pressure fluids, unless they are safely contained, are extremely
hazardous. Always relieve fluid pressure before adjusting or servicing high
pressure equipment. A jet of high-pressure fluid can cut like a knife and
cause serious bodily injury, amputation, or death. Fluids penetrating the
skin can also cause toxic poisoning.
If you suffer a fluid injection injury, seek medical care immediately. If
possible, provide a copy of the MSDS for the injected fluid to the health care
provider.

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The National Spray Equipment Manufacturers Association has created a
wallet card that you should carry when you are operating high-pressure
spray equipment. These cards are supplied with your equipment. The
following is the text of this card:
WARNING: Any injury caused by high pressure liquid can be serious. If
you are injured or even suspect an injury:
SGo to an emergency room immediately.
STell the doctor that you suspect an injection injury.
SShow him this card
STell him what kind of material you were spraying
MEDICAL ALERT—AIRLESS SPRAY WOUNDS: NOTE TO PHYSICIAN
Injection in the skin is a serious traumatic injury. It is important to treat the
injury surgically as soon as possible. Do not delay treatment to research
toxicity. Toxicity is a concern with some exotic coatings injected directly into
the bloodstream.
Consultation with a plastic surgeon or a reconstructive hand surgeon may
be advisable.
The seriousness of the wound depends on where the injury is on the body,
whether the substance hit something on its way in and deflected causing
more damage, and many other variables including skin microflora residing
in the paint or gun which are blasted into the wound. If the injected paint
contains acrylic latex and titanium dioxide that damage the tissue’s
resistance to infection, bacterial growth will flourish. The treatment that
doctors recommend for an injection injury to the hand includes immediate
decompression of the closed vascular compartments of the hand to release
the underlying tissue distended by the injected paint, judicious wound
debridement, and immediate antibiotic treatment.
Fire Safety
To avoid a fire or explosion, follow these instructions.
SGround all conductive equipment. Use only grounded air and fluid
hoses. Check equipment and workpiece grounding devices regularly.
Resistance to ground must not exceed one megohm.
SShut down all equipment immediately if you notice static sparking or
arcing. Do not restart the equipment until the cause has been identified
and corrected.
SDo not smoke, weld, grind, or use open flames where flammable
materials are being used or stored.
SDo not heat materials to temperatures above those recommended by
the manufacturer. Make sure heat monitoring and limiting devices are
working properly.

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Fire Safety (contd)
SProvide adequate ventilation to prevent dangerous concentrations of
volatile particles or vapors. Refer to local codes or your material MSDS
for guidance.
SDo not disconnect live electrical circuits when working with flammable
materials. Shut off power at a disconnect switch first to prevent
sparking.
SKnow where emergency stop buttons, shutoff valves, and fire
extinguishers are located. If a fire starts in a spray booth, immediately
shut off the spray system and exhaust fans.
SShut off electrostatic power and ground the charging system before
adjusting, cleaning, or repairing electrostatic equipment.
SClean, maintain, test, and repair equipment according to the instructions
in your equipment documentation.
SUse only replacement parts that are designed for use with original
equipment. Contact your Nordson representative for parts information
and advice.
Halogenated Hydrocarbon Solvent Hazards
Do not use halogenated hydrocarbon solvents in a pressurized system that
contains aluminum components. Under pressure, these solvents can react
with aluminum and explode, causing injury, death, or property damage.
Halogenated hydrocarbon solvents contain one or more of the following
elements:
Element Symbol Prefix
Fluorine F “Fluoro-”
Chlorine Cl “Chloro-”
Bromine Br “Bromo-”
Iodine I “Iodo-”
Check your material MSDS or contact your material supplier for more
information. If you must use halogenated hydrocarbon solvents, contact
your Nordson representative for information about compatible Nordson
components.
Action in the Event of a Malfunction
If a system or any equipment in a system malfunctions, shut off the system
immediately and perform the following steps:
SDisconnect and lock out system electrical power. Close hydraulic and
pneumatic shutoff valves and relieve pressures.
SIdentify the reason for the malfunction and correct it before restarting the
system.
Disposal
Dispose of equipment and materials used in operation and servicing
according to local codes.

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Safety Labels
See Figure 1 for the location of the safety label on the applicator. The
safety label is provided to help you operate and maintain your equipment
safely. The label reads:
WARNING: Do not open when an explosive gas atmosphere is present.
Max ambient temperature: 140 _F (60 _C)
Safety Label
(All Models)
R
ATMOSPHERE IS AN EXPLOSIVE GAS
MODEL A20A
OHIO 44001 PRESENT.
NORDSON CORP. USA
DO NOT OPEN WHEN
WHEN
SPHERE
F(60 C)
Figure 1 Safety Label Location

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Description
The A20A Electric Spray Gun is a fast cycle, airless automatic spray gun
designed for use in high-speed container coating applications. The gun can
be used with the Nordson iTrax System or the Flow Sentry System.
Features
SOn-line removable valve/seat module
SIntegral electric solenoid
SNo packing cartridge or moving seals
SStainless steel construction of wetted parts
SCompatibility with a wide range of wide range of water-based and
solvent-based lacquers
SUses Nordson Controlled Pattern or Cross-Cut nozzles
SCan be used in dead-end or circulating systems
Models
See Figure 2. The A20A applicator is available in the following models:
Part Description Approvals
135576 Short Standard FM
141426 Short ATEX CE/ATEX
135575 Extended Standard FM
141425 Extended ATEX CE/ATEX
144466 8 in. Extended None
The CE/ATEX approved models have a covered solenoid end.
R
R
R
Short Standard Extended Standard
8 inch Extended Standard
R
R
Short ATEX Extended ATEX
Figure 2 A20A Models

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Specifications
Dimensions and Weight
Length:
SShort Standard 124 mm (4.88 in.)
SShort ATEX
SExtended Standard 168 mm (6.62 in.)
SExtended ATEX
S8 in. Extended
Width 75 mm (2.94 in.)
Height 67 mm (2.62 in.)
Weight:
SShort Standard 1.13 kg (2.5 lbs)
SShort ATEX
SExtended Standard 1.25 kg (2.75 lbs)
SExtended ATEX
S8 in. Extended
Electrical
Driver requirements 24 Vdc, 1.5 amps
Connection 1/2-in. NPT female conduit fitting
Fluid
Maximum fluid pressure 104 bar (1500 psi)
Maximum fluid temperature 60 _C (140 _F)
Connection 1/2-20 JIC elbow fittings
Ratings and Label Information
Ex db IIB T3 Gb
Baseefa02ATEX0049X
1180
10,500kPa Max Press
2 G
24 Vdc Max
1.5 amp Max
(Ta = −20 _C to
+60 _C)
CE/ATEX Approved
24 Vdc 1.5 amps
Max Press 1500 psi
(10400 kPa)
Class 1, Group D
T3C Ta=60 _C
FM −US and Canada Approved
US
C
Figure 3 Ratings and Label Information

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Installation
WARNING: Allow only qualified personnel to perform the following tasks.
Follow the safety instructions in this document and all other related
documentation.
WARNING: The purchaser should make the manufacturer aware of any
external effects or aggressive substances that the equipment may be
exposed to.
Mounting
Mount the gun to any mounting plate, using the two #10−32 x 2.5 in. screws
shipped with the gun and the two holes in the body. Refer to the
Specifications for gun dimensions.
Fluid Connections
WARNING: An approved pressure relief device set at 104 bar (1500 psi)
must be installed in the fluid line to the gun. The fluid hoses connected to
the gun must have a minimum burst pressure of 104 bar (1500 psi).
The supply and return hoses can be connected to either one of the fluid
fittings on the gun. The fittings are 1/2-20 JIC male connectors.
If using the gun in a dead-end system, replace the unused fitting with a
1/4in. NPT stainless steel plug.
Electrical Connections
The gun can be connected to any 24 Vdc driver that supplies a minimum of
1.5 amps (such as a Nordson FET-1 or FET-2 timer). The solenoid housing
has a 1/2-in. NPT female thread for connection to an electrical conduit.
The solenoid housing can be rotated by loosening or removing the jam nut
and housing nut, or on CE approved models, the set screw and housing nut.
R
R
1
4
3
2
5
67
8
Figure 4 Installation
1. Housing nut (CE)
2. Set screw (CE)
3. Jam nut
4. Housing nut
5. Fluid fittings
6. Conduit connection
7. CO-plate plug
8. Transducer plug

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Baseefa Special Conditions for Safe Use
1. The permanently attached cables shall be suitably terminated and
protected against impact.
2. The supply to the solenoid coil must be protected with a fuse rated up
to 2A.
3. It is considered the responsibility of the user/installer to provide an earth
connection facility at the termination point of the solenoid coil leads and
provide continuity between this facility and the external termination
facility on the spray gun.
Spray Monitor System Installation
To use the A20A spray gun with the Nordson iTrax System or the Flow
Sentry System, a CO-plate and pressure transducer must be installed in the
gun. These devices allow the systems to detect an abnormal changes in
spray pressure that could cause rejects.
Transducer Installation
See Figure 4. Remove the transducer plug (8). Install the transducer or
swivel assembly into the transducer port. Refer to the Canworks Pressure
Transducer/Swivel Assembly instruction sheet for installation procedures.
CO-Plate Installation
Refer to Table 1 to select the correct CO-plate for your application.
1. See Figure 4. Remove the CO-Plate plug (7).
2. Make sure the O-ring is in place on the CO-plate.
3. Loosely thread the CO-plate onto the CO-plate puller (shipped with the
gun).
4. Insert the puller into the port and push it to seat the O-ring.
5. Partially unscrew the puller from the CO-plate, then push it again to
make sure the CO-plate is seated.
6. Unscrew the puller from the CO-plate.
7. Make sure the O-ring is in place on the CO-plate plug. Install the
CO-plate plug and tighten it securely.

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CO-Plate Selection
Cross-reference your nozzle size with your spray pressure to find the
CO-plate part number.
Table 1 CO-Plate Selection
Spray Pressures
Nozzle
Size (in.)
27 Bar
(400 psi)
34 Bar
(500 psi)
41 Bar
(600 psi)
48 Bar
(700 psi)
55 Bar
(800 psi)
62 Bar
(900 psi)
69 Bar
(1000 psi)
76 Bar
(1100 psi)
0.015 247707
(015)
247707
(015)
247708
(02)
247708
(02)
247708
(02)
247709
(025)
247709
(025)
247709
(025)
0.03 247709
(025)
247710
(03)
247710
(03)
247711
(04)
247711
(04)
247711
(04)
247712
(05)
247712
(05)
0.04 247710
(03)
247711
(04)
247711
(04)
247712
(05)
247713
(06)
247713
(06)
247713
(06)
247714
(075)
0.06 247712
(05)
247713
(06)
247713
(06)
247714
(075)
247714
(075)
247715
(09)
247716
(105)
247716
(105)
0.075 247713
(06)
247714
(075)
247714
(075)
247715
(09)
247716
(105)
247717
(12)
247718
(14)
247718
(14)
0.09 247714
(075)
247715
(09)
247716
(105)
247717
(12)
247717
(12)
247718
(14)
247718
(14)
247719
(16)
0.12 247716
(105)
247717
(12)
247718
(14)
247719
(16)
247719
(16)
247720
(20)
247720
(20)
247720
(20)
0.14 247717
(12)
247718
(14)
247719
(16)
247719
(16)
247720
(20)
247720
(20)
247721
(25)
247721
(25)
0.20 247719
(16)
247720
(20)
247721
(25)
247721
(25)
247722
(30)
247722
(30)
0.30 247721
(25)
247722
(30) 247722
CO plate
CO-
p
late
NOTE: The CO-plate designation
is on the front of the CO-plate.
247722
(30)
CO
-p
l
ate
designation
part number
CO-plate

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Operation
WARNING: Allow only qualified personnel to perform the following tasks.
Follow the safety instructions in this document and all other related
documentation.
WARNING: This equipment can be dangerous unless it is used in
accordance with the rules laid down in the manual.
The A20A gun operation is controlled by the timer or pattern controller and
driver used to trigger the spray gun. Refer to controller and driver manuals
for operation procedures.
CAUTION: The gun is designed for high-cycle applications. It is not
designed to be triggered ON for long periods of time. Damage to the
solenoid coil may occur. When flushing the fluid system, the gun should not
triggered ON for more than 5 seconds.
Maintenance
WARNING: Allow only qualified personnel to perform the following tasks.
Follow the safety instructions in this document and all other related
documentation.
SFlush the gun periodically with a solvent or cleaning solution compatible
with your coating material. The interval required depends on the
application.
SClean the nozzle daily.
SLeave the system full of coating material on overnight shutdowns.
SFor longer shutdowns, flush the system and leave it full of solvent or
cleaning solution.

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Troubleshooting
WARNING: Allow only qualified personnel to perform the following tasks.
Follow the safety instructions in this document and all other related
documentation.
Problem Possible Cause Corrective Action
1. Gun fails to trigger Poor electrical connection Check the gun, driver, and timer
electrical connections.
Ball and seat module installed
incorrectly
Remove, clean, and reinstall the ball
and seat module. Refer to Ball and
Seat Module Replacement.
Failed solenoid coil Disconnect the coil wires and check
the coil resistance with an ohmmeter.
The reading should be approximately
18 ohms. Replace the coil if the
resistance check fails. Refer to
Solenoid Coil Replacement.
2. Fluid is spitting or
leaking from nozzle
Dirty or worn ball and seat module Clean or replace the ball and seat
module. Refer to Ball and Seat
Module Replacement.
3. Fluid is leaking
around nozzle nut
Dirty or damaged metal sealing
surfaces
Clean or replace the nozzle, nozzle
nut, or ball and seat module. Refer
to Ball and Seat Module
Replacement.
4. Fluid leaks between
gun body and
solenoid housing
and/or seat
Damaged O-rings Replace the O-rings. Refer to Ball
and Seat Module Replacement and
Armature Replacement.

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Repair
WARNING: Allow only qualified personnel to perform the following tasks.
Follow the safety instructions in this document and all other related
documentation.
Ball and Seat Module Replacement
WARNING: To prevent serious injury to personnel and damage to
equipment, relieve system fluid pressure and disconnect and lock out
system electrical power before repairing the spray gun.
CAUTION: If you disassemble the ball and seat module for inspection and
cleaning, mark the ball tip pin location so you can install the ball tip in the
same position it was in when it was removed. If you install it 180_out of
position, the ball tip will no longer seal against the seat, allowing fluid to leak
from the nozzle.
See Figure 5. Use the ball and seat service kit to replace the ball and seat
module. You do not have to remove the gun from its mounting.
Removal
1. Relieve system fluid pressure. Disconnect and lock out system
electrical power.
2. Remove the nozzle nut (1) and the nozzle (2).
3. Remove the retaining nut (3).
4. Unscrew the ball and seat module (4) from the armature shaft.
Installation
1. Install a new O-ring (5) in the gun body or extension groove. The O-ring
is included in the ball and seat service kit.
2. Carefully thread the new ball and seat module (4) onto the
armature shaft (6) until it bottoms out on the armature shaft flange.
Tighten the module finger tight. Do not apply more than 0.56 NDm
(5 in.-lbs) of torque.
3. Rotate the seat housing (8) counterclockwise (1/4turn maximum) until
the first set of slots engage with the gun body pins (7). Do not loosen
the threaded connection to engage the slots with the body pins.
4. Place the retaining nut over your finger. Using this finger to hold the ball
and seat module tight against the gun body, screw the retaining nut onto
the gun body or extension. Tighten the retaining nut to 14−20 NDm
(10−15 ft-lbs).
5. Install the nozzle and nozzle nut. Tighten the nozzle nut to 34 NDm
(25 ft-lbs) maximum.

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Ball and Seat Module Replacement (contd)
6
5
4
3
2
1
8
7
S
SS
Figure 5 Ball and Seat Module Installation
1. Nozzle nut
2. Nozzle
3. Retaining nut
4. Ball and seat module*
5. O-ring*
6. Armature shaft
7. Body pins
8. Seat housing
Note: Parts marked with * are included in ball and seat kit.
Solenoid Coil Replacement
WARNING: To prevent serious injury to personnel and damage to
equipment, relieve system fluid pressure and disconnect and lock out
system electrical power before repairing the spray gun.
See Figure 6. Use the coil service kit to replace the solenoid coil.
1. Relieve system fluid pressure. Disconnect and lock out system
electrical power.
2. Remove the gun from its mounting if necessary.
3. Disconnect the coil wires (4) from the driver or driver cable.
4. Disconnect the conduit from the solenoid housing (4). Pull the coil wires
from the conduit.

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5. Unscrew the jam nut or loosen the set screw (5 or 6). Unscrew the
housing nut (3) and remove the solenoid housing from the solenoid
sleeve (1). Discard the parts you removed.
6. Slide the new solenoid housing over the solenoid sleeve.
7. Thread the new housing nut on the sleeve and tighten securely.
8. Thread the new jam nut on the sleeve and tighten securely, or install and
tighten the set screw securely.
9. Run the new coil wires through the conduit. Reconnect the conduit and
coil wires.
MODEL US PATENT NO 5,078,325
OTHER PAT.PEND
NORDSON MFG.
A20A
CORP
USA
R
MODEL US PATENT NO 5,078,325
OTHER PAT.PEND
NORDSON MFG.
A20A
CORP
USA
R
1
2
3
5
4
1
2
3
6
4
Figure 6 Solenoid Coil Replacement
1. Solenoid sleeve
2. Solenoid housing and coil*
3. Housing nut*
4. Coil wires
5. Set screw (CE approved
models)*
6. Jam nut*
Note: Parts marked with * are included in the coil service kit.
Armature Replacement
WARNING: To prevent serious injury to personnel and damage to
equipment, relieve system fluid pressure and disconnect and lock out
system electrical power before repairing the spray gun.
See Figure 7. Use the armature service kit to replace the armature.
1. Relieve system fluid pressure. Disconnect and lock out system
electrical power.
2. Remove the gun from its mounting.

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Armature Replacement (contd)
3. Remove the nozzle nut, nozzle, and ball and seat module. Refer to Ball
and Seat Replacement in this section.
NOTE: On guns with 8-in. extensions, you do not have to remove the
extension assembly.
4. Remove the solenoid coil. Refer to Solenoid Coil Replacement in this
section. You do not have to disconnect the solenoid wires or conduit.
5. Unscrew the fillister-head screw (not shown) and solenoid sleeve (1).
Remove the long and short springs (2, 3).
6. Pull the armature (4) and fluid guide (6) out of the body. If it cannot be
removed by hand, turn the gun upside down and tap on the threaded
end of the armature with a small diameter brass rod or other soft tool.
7. Insert the armature into the body, making sure the pins on the shaft go
into the slots in the body. Press the fluid guide into the body with your
fingers.
8. Rebuild the gun, using the rest of the new parts from the armature kit.
Tighten threaded parts securely. Refer to Solenoid Coil Replacement
and Ball and Seat Replacement in this section.
S
S
S S
123
4
56
7
Figure 7 Armature Replacement
1. Solenoid sleeve
2. Short outer spring*
3. Long inner spring*
4. Armature*
5. O-ring*
6. Fluid guide
7. O-ring*
Note: Parts marked with * are included in the armature service kit.

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Parts
To order parts, call the Nordson Finishing Customer Support Center at
(800) 433−9319 or your local Nordson representative. Use these parts
lists and illustrations to locate and describe parts correctly.
Gun Models
Refer to the indicated pages for the model parts lists.
Part Description Page
135576 GUN, A20A standard (FM) 18
135575 GUN, A20A, extended (FM) 18
141426 GUN, A20A standard, ATEX 20
141425 GUN, A20A, extended, ATEX 20
144466 GUN, A20A, extended, 8-inch 22
Service Kits
Keep one of each type of service kit for your gun on hand to reduce
downtime.
Part Service Kit
Gun Models
135576 135575 141426 141425 144466 Page
135557 Ball and seat X X X X X 24
106300 Coil, standard X X X 24
141447 Coil, ATEX X X 24
135560 Armature, standard X X 25
135559 Armature, extended X X 25
144704 Armature, 8-inch extended X 25
135558 Buna-N soft goods X X X X X 25
334842 EPR soft goods X X X X X 25

A20A Automatic Electric Airless Spray Gun
18
Part 108182-03 E2017 Nordson Corporation
Standard Short and Extended A20A Spray Guns
See Figure 8. This parts list covers the standard short and extended
models. The only difference between the short and extended models is the
length of the gun body and the armature.
Item Part Description Quantity Note
−135576 GUN, A20A standard 1
−135575 GUN, A20A, extended 1
1 984171 SNUT, hex, jam, 1/2-20, steel, zinc 1 A
2 247641 SRETAINER, CO-Plate 1
3 945020 SO-RING, hotpaint, 3/16 in. tube 1 C
4 123200 SNUT, nozzle, anti-foul, stainless steel 1
5 135571 SNUT, retaining 1
6 973299 SPLUG, O-ring, straight thread, 3/8−24 2
7- - - - - - SBODY, A20A standard or extended gun 1
8 981022 SSCREW, fillister head, #6−32 x 0.375 in.,
slotted, zinc
1C, D
9- - - - - - SHOUSING, solenoid 1 A
10 246067 SCAP, solenoid housing 1 A
11 246066 SNUT, housing 1 A
12 - - - - - - SMODULE, ball & seat 1 B
13 940150 SO-RING, hotpaint, 0.563 x 0.688 x 0.063 in. 1B, C, D
14 - - - - - - SARMATURE, standard or extended 1 D
15 135562 SGUIDE, fluid 1
16 940190 SO-RING, hotpaint, 0.813 x 0.938 x 0.063 in. 1C, D
17 246051 SSLEEVE, solenoid 1
18 972029 SCONNECTOR, male, 37_, 1/2−20 x 1/4in. NPT,
stainless steel
2
19 270863 SSPRING, compression, 0.415 x 0.247 OD x
0.015 in.
1 D
20 270905 SSPRING, compression, 1.00 x 0.157 OD x
0.022 in.
1 D
21 901109 SCOIL, solenoid 1 A
22 983604 SSPRING, washer, curved 1 A
NS 981116 SSCREW, fillister head, #10−32 x 2.50 in., steel,
zinc
2 E
NS 983120 SWASHER, lock, split, #10, steel, nickel 2 E
NS 247638 SPULLER, CO-Plate 1
NS 247646 SCARD, medical alert, injection 1
NS 152999 SWRENCH 1
NS 901905 SBRUSH 1
NS 149237 SCOVER, CleanSleeve, mini, 500 pieces 1
NOTE A: Included in standard coil service kit.
B: Included in ball and seat service kit.
C: Included in soft goods service kit. To replace with EPR O-rings refer to EPR Soft Goods kit on page 25.
D: Included in standard and extended armature service kit.
E: Use for mounting gun.
NS: Not Shown