Donaldson Torit WSO 20 User manual

IOM AK0300801 (ENG)
Revision 3

Process owners/operators have important responsibilities relating to combustible hazards.
Process owners/operators must determine whether their process creates combustible dust,
fume, or mist. If combustible dust, fume, or mist is generated, process owners/operators should at a
minimum:
• Comply with all applicable codes and standards. Among other considerations, current NFPA standards
require owners/operators whose processes involve potentially combustible materials to have a current
Hazard Analysis, which can serve as the foundation for their process hazard mitigation strategies.
• Prevent all ignition sources from entering any dust collection equipment.
• Design, select, and implement fire and explosion mitigation, suppression, and isolation strategies that
are appropriate for the risks associated with their application.
• Develop and implement maintenance work practices to maintain a safe operating environment, ensuring
that combustible dust, fume, or mist does not accumulate within the plant.
Donaldson recommends process owners/operators consult with experts to insure each of these
responsibilities are met.
As a manufacturer and supplier of Industrial Filtration Products, Donaldson can assist process owners/
operators in the selection of filtration technologies. However, process owners/operators retain all
responsibility for the suitability of fire and explosion hazard mitigation, suppression, and isolation strategies.
Donaldson assumes no responsibility or liability for the suitability of any fire and/or explosion mitigation
strategy, or any items incorporated into a collector as part of an owner/operators hazard mitigation strategy.
Improper operation of a dust control system may contribute to conditions in the work area or facility that
could result in severe personal injury and product or property damage. Check that all collection equipment is
properly selected and sized for the intended use.
DO NOT operate this equipment until you have read and understand the instruction warnings in the
Installation and Operations Manual. For a replacement manual, contact Donaldson Torit.
This manual contains specific precautionary statements relative to worker safety. Read thoroughly and comply
as directed. Discuss the use and application of this equipment with a Donaldson Torit representative. Instruct all
personnel on safe use and maintenance procedures.
Donaldson Company, Inc.
Model Number _____________________________ Serial Number ______________________________
Ship Date _________________________________ Installation Date _____________________________
Customer Name _______________________________________________________________________
Address _____________________________________________________________________________
____________________________________________________________________________________
Filter Type ____________________________________________________________________________
Accessories __________________________________________________________________________
Other________________________________________________________________________________
Data Sheet

DANGER indicates a hazardous situation which, if not avoided, will result
in death or serious injury.
WARNING indicates a hazardous situation which, if not avoided, could
result in death or serious injury.
CAUTION, used with the safety alert symbol, indicates a hazardous
situation which, if not avoided, could result in minor or moderate injury.
NOTICE is used to address practices not related to personal injury that
may result in damage to equipment.
NOTICE
WSO Mist Collector,WSO 20, 25-1, 25-2, and 25-3
i
Magnehelic®and Minihelic®are registered trademarks of Dwyer Instruments, Inc.
Contents
Description................................................................................1
Purpose and Intended Use.....................................................1
Rating and Specification Information...................................2
Operation...................................................................................3
Inspection on Arrival...............................................................4
Installation Codes and Procedures ......................................4
Installation.................................................................................4
Site Selection, Grade-Mounted Units ..............................4
Site Selection, Ceiling-Mounted Units (WSO 20
and 25-1): ...............................................................................5
Unit Location.............................................................................5
Rigging Instructions.................................................................6
Hoisting Information ............................................................6
Electrical Wiring.......................................................................6
Standard Equipment................................................................7
Typical Floor Mount Installation ........................................7
Blower and Motor (Unpowered WSO 25-2 and 25-3).....9
Ceiling Mount (WSO 20 and 25-1)...................................11
P-Trap Installation..............................................................12
Inlet Collar Installation ......................................................12
Electrical Connection .......................................................13
Motor Starter Control Box ................................................13
Preliminary Start-Up Check .................................................14
Maintenance Information.....................................................15
Operational Checklist ........................................................15
Filter Removal and Installation.........................................15
First Stage Filter Cleaning and Installation ................15
Primary Filter Installation ..............................................16
Final Filter Installation (WSO 20 and 25-1)..................17
Final Filter Installation (WSO 25-2 and 25-3) ..............17
P-Trap Service ....................................................................18
P-Trap with Y-Strainer, Screen Cleaning and Removal18
Drain Collection Container................................................19
Optional Equipment................................................................20
Factory-Installed HEPA/95% DOP Filter..........................20
Field Installation (WSO 20 and 25-1) ...............................20
Latch and Afterfilter Installation ..................................20
Magnehelic®or Minihelic® Installation.........................21
Remote-Mount Magnehelic Installation ........................21
Damper and Silencer, TBI.................................................23
Sprinkler Installation..........................................................24
WSO 20 Sprinkler Installation.......................................24
WSO 25-1 Sprinkler Installation ...................................25
WSO 25-2 and 25-3 Sprinkler Installation...................25
Drain Collection Container................................................25
Troubleshooting......................................................................26

Combustible materials such as buffing lint, paper, wood, metal dusts, weld fume, or flammable
coolants or solvents represent potential fire and/or explosion hazards. Use special care when
selecting, installing, and operating all dust, fume, or mist collection equipment when such combustible
materials may be present in order to protect workers and property from serious injury or damage due to a
fire and/or explosion.
Consult and comply with all National and Local Codes related to fire and/or explosion properties of
combustible materials when determining the location and operation of all dust, fume, or mist collection
equipment.
Standard Donaldson Torit equipment is not equipped with fire extinguishing or explosion protection systems.
1
Donaldson Company, Inc.
Description
Designed for versatility, the WSO (Water, Smoke, and Oil)
mist collector is specifically engineered for water-based,
smoke, and oil-based mist applications. WSO mist
collector, Models WSO 20, 25-1, 25-2, and 25-3 collect
airborne mist such as oil, water-soluble, semi-synthetic
and synthetic coolant from machining operations. Two
stages of filtration, plus an optional HEPA or 95% DOP
filter, provide a cleaner, healthier work environment as
well as a more cost effective means of mist collection.
With maximum airflow capacities up to 2,000 cfm for
WSO 20 and 25-1 and 5,500 cfm for WSO 25-2 and 25-3,
the WSO is a strategic component to meeting industrial
and government air-quality standards. The high
efficiency filter cartridges allow air and coolants to be
recycled.
Designed to increase the versatility of the unit, a variety
of filter media specifically designed for mist collection
is a standard offering on the product line. The WSO
20 contains a 20 inch tall primary filter and the WSO
25-1, 25-2, and 25-3 contain a 25 inch tall primary filter
uniquely designed for either water-based coolants,
straight oils, or thermally-generated smoky applications.
Standard options include drain collection containers,
P-Traps, and afterfilters.
WSO models 20 and 25-1 include the blower and motor.
WSO models 25-2 and 25-3 are available with or without
a blower and motor.
Purpose and Intended Use
Misuse or modification of
this equipment may result in
personal injury.
Do not misuse or modify.
Airborne mist is small droplets of metalworking fluids
suspended in the air. Metalworking fluids include
straight oils, water-soluble coolants, semi-synthetic and
synthetic coolants. These fluids perform a variety of
functions such as lubricating or cooling the part or the
tool, flushing chips away from the part, and suppressing
dust and smoke.
Mist is created two ways: mechanical action or thermal
effects. Mechanical action involves coolant used for
light lubrication and generally creates mist greater than
one micron in size. Thermal effects occur when heat
vaporizes the coolant, the vapor cools and recondenses
into a mist. Thermal effects create mist from 0.01 to 1
micron in size. Other contaminants, such as dust from
the part or the tool or smoke from the vaporization
of the oil or coolant are also generated when using
metalworking fluids.
The WSO mist collector is not designed to handle water
mist alone. There should be some type of oil content
to allow coalescing or water vapor will simply pass
through the filters. The extremes of very heavy oil and
light, thin oil should be avoided. Very heavy oil, similar
to tar consistency, will not drain while very light, thin oil,
similar to paint thinner consistency, may evaporate.

200-Volt, 380-Volt, 3 Ph, 50Hz/60 Hz

3
Donaldson Company, Inc.
primary filter cartridge
clean-air outlet
coalesced
large droplets
first-stage filter
dirty-air inlet
clean-air plenum
blower and motor
p-trap (drain)
optional afterfilter
Unit Operation, WSO 25-1 shown
Operation
During normal operation, contaminated air enters the
unit through one or both dirty-air inlets located on each
side, toward the bottom of the unit. The incoming air
slows and turns upward, causing large mist droplets
and particles to fall out of the air stream and into the
hopper. The air passes through a reusable first-stage
filter designed to collect and coalesce large droplets
and particles.
The primary stage of filtration is the pleated filter
cartridge specifically designed to collect, coalesce, and
drain fine mist. As the mist coalesce, the droplets are big
enough to run down the cartridge and drain back into
the collector. The droplets will drain on both the inside
and outside of the cartridge. Liquid that collects on the
inside of the cartridge drains through the bottom portion
of the porous media and into the hopper. Clean, mist-free
air exits the cartridge and discharges through the top of
the collector.

WSO Mist Collector,WSO 20, 25-1, 25-2, and 25-3
4
Inspection on Arrival
1. Inspect unit on delivery.
2. Report any damage to the delivery carrier.
3. Request a written inspection report from the Claims
Inspector to substantiate any damage claim.
4. File claims with the delivery carrier.
5. Compare unit received with description of product
ordered.
6. Report incomplete shipments to the delivery carrier
and your Donaldson Torit representative.
7. Remove crates and shipping straps. Remove loose
components and accessory packages before lifting
unit from truck.
8. Check for hardware that may have loosened during
shipping.
9. Use caution removing temporary covers.
Installation Codes and Procedures
Codes may regulate recirculating
filtered air in your facility.
Consult with the appropriate authorities
having jurisdiction to ensure compliance
with all national and local codes regarding
recirculating filtered air.
Safe and efficient operation of the unit depends on
proper installation.
Authorities with jurisdiction should be consulted
before installing to verify local codes and installation
procedures. In the absence of such codes, install unit
according to the National Electric Code, NFPA No.
70-latest edition and NFPA 91 (NFPA 654 if combustible
dust is present).
A qualified installation and service agent must complete
installation and service of this equipment.
All shipping materials, including shipping covers,
must be removed from the unit prior to, or during unit
installation.
Failure to remove shipping
materials from the unit will
compromise unit performance.
Inspect unit to ensure all hardware is properly installed
and tight prior to operating collector.
Installation
Site selection must account
for wind, seismic zone, and
other live-load conditions when selecting the
location for all units.
Codes may regulate acceptable locations for
installing dust collectors. Consult with the
appropriate authorities having jurisdiction to
ensure compliance with all national and local
codes regarding dust collector installation.
Site Selection, Grade-Mounted Units
Ensure weight of oil-laden unit
plus weight of required materials
and equipment will be adequately supported.
Failure to comply may result in personal injury
and/or property damage.
When outdoor locations are
selected, always mount motors
with drain holes pointed down for proper
drainage of moisture.
The unit can be located on a flat reinforced concrete
foundation.
Provide clearance from heat sources and interference
with utilities when selecting the location.
Prepare the foundation in the selected location.
Install anchor bolts a minimum of 1 3/4-inches above
foundation.
Locate the collector to ensure easy access to
electrical and compressed-air connections and routine
maintenance.
NOTICE
NOTICE

5
Donaldson Company, Inc.
Site Selection, Ceiling-Mounted Units
(WSO 20 and 25-1):
Lifting lugs on the unpowered unit
(25-2 or 25-3) are not intended
for ceiling suspension. Unit is floor-mount only.
Failure to comply may result in personal injury
and/or property damage.
Ensure weight of oil-laden unit plus weight
of required materials and equipment will
be adequately supported. Failure to comply
may result in personal injury and/or property
damage.
WSO 20 and 25-1 can be suspended or hung from
overhead supports. The supports must be adequate to
carry the live load of the unit and installation performed
to reduce sway or vibration to the unit. The dry unit
weight is shown on the specification control drawing
shipped with the unit.
The live load will include the weight of all ancillary
hardware attached to the mist collector, as well as the
weight of the mist-laden, wet filters. Consult the coolant
MSDS for the specific gravity of the coolant to estimate
the weight of the mist-laden, wet filters.
Provide clearance from heat sources and interference
with utilities when selecting the location for suspended
units.
Unit Location
Donaldson Torit equipment
is not designed to support
site-installed ducts, interconnecting piping,
or electrical services. All ducts, piping, or
electrical services supplied by others must
be adequately supported to prevent severe
personal injury and/or property damage.
When hazardous conditions or materials are
present, consult with local authorities for the
proper location of the collector.
If combustible materials will
be processed through this
collector, local codes may require the collector
be located either outside or adjacent to an
exterior wall to accommodate devices related
to a fire or explosion mitigation strategy.
Consult local codes prior to installation.
Foundation or overhead (for WSO 20 and 25-1) support
must be sized to accommodate the entire weight of the
unit, plus the weight of the collected material, piping,
and ductwork.

Refer to applicable OSHA regulations and local codes
when using cranes,forklifts, and other lifting equipment.
9/16-in Socket)

7
Donaldson Company, Inc.
Standard Equipment
The collector has a high center-
of-gravity and may overturn if not
secured properly.
Secure the collector to the lifting device.
Use care when moving the unit.
The WSO mist collector is shipped in two sections, an
inlet plenum with legs and a filter cabinet section with
a blower and motor (for powered WSO 20 and 25-1
models) or without a blower and motor (for unpowered
WSO 25-2 and 25-3 models).
Typical Floor Mount Installation
1. Prepare the foundation in the selected location.
Install customer-supplied 3/8-16 anchor bolts a
minimum of 1 1/2-inches above foundation. Anchor
bolt pattern is shown on the Specification Control
drawing.
2. Using a crane or forklift, raise the inlet plenum to the
required height.
Note: When using a crane, use clevis pins and a sling
attached to four lifting lugs.
3. For the WSO 20, attach legs to the outside of the
unit’s stub legs with supplied fasteners. Do not
tighten hardware at this time.
4. Lower the inlet plenum with legs to the anchor bolts.
5. Level inlet plenum and secure all hardware.
6. Apply supplied sealant to the top flange of the
inlet plenum.
7. Remove the first stage and primary filters from the
filter cabinet and set aside.
8. Using a crane or forklift, raise the filter cabinet
section to the required height. See below illustration
for correct lifting orientation.
9. Set cabinet on top of the inlet plenum flange and
attach with the supplied fasteners.
10. Remove crane or forklift.
11. Re-install the first stage and primary filters.
inlet plenum
foundation anchor bolt
leg
Inlet Plenum Installation, WSO 25-2 shown

WSO Mist Collector,WSO 20, 25-1, 25-2, and 25-3
8
Completed Installation
Filter Cabinet Installation
Lifting Lug Angle
Incorrect Lifting Orientation
(correct lifting orientation
shown to the right)
filter
cabinet
sealant
inlet
plenum
lifting lug
Correct Lifting
Orientation
angle not to exceed
30° from vertical
(minimum 60°
from horizontal)
clevis
pin
lifting
lug
spreader bar
Completed Installation, Powered WSO 25-2 shown

9
Donaldson Company, Inc.
Blower and Motor (Unpowered WSO 25-2
and 25-3)
The two types of blowers, Torit Backward Incline, TBI,
and Torit Radial Blade, TRB, are installed following the
same procedure. Both can be ordered for top mount.
1. The blower and motor are shipped assembled and
partial disassembly is required before installing.
2. Remove eight motor-mount bracket fasteners;
remove the motor, motor-mount bracket, and blower
wheel as an assembly as shown.
3. Turn housing over and apply sealant to the outside-
edge of the bolt pattern on the blower housing.
Mount the blower housing to the collector using the
inlet cone fasteners.
4. Apply sealant to the outside-edge of the bolt pattern
on the blower housing. Reinstall the motor, bracket,
and blower wheel assembly. Align the tab on the
blower housing with the slot in the motor-mount
bracket.
5. Rotate blower wheel after installation to ensure
proper clearance between the inlet cone and the
blower wheel.
Do not allow the fan wheel to
come loose from the motor as it
may cause severe injury or property damage.
To ensure proper attachment of the fan wheel:
Tighten all setscrews in fan wheel.*
Tighten all setscrews in bearings.*
Repeat after 8 hours of operation.
Repeat again after two weeks of operation.
Reference Wheel Setscrew Torque Table.
Wheel Setscrew Torque
Setscrew Size
Diameter
Carbon Steel Setscrew
Torque*
In. Lb. - In. Lb. - Ft.
1/4 75 6.2
5/16 144 12
3/8 252 21
7/16 396 33
1/2 600 50
5/8 1164 97
3/4 2016 168
7/8 3204 267
1 4800 400
*Stainless steel setscrews are not hardened and should not
be tightened to more than half of the values shown.

WSO Mist Collector,WSO 20, 25-1, 25-2, and 25-3
10
blower
housing
sealant
collector
mounting surface
sealant
motor mount
blower wheel
sealant
spacer ring
Top Mount Power Pack
with Spacer Ring
Blower and Motor, TBI with Spacer Ring

11
Donaldson Company, Inc.
Ceiling Mount (WSO 20 and 25-1)
Failure to lift the collector
correctly can result in severe
personal injury or property damage.
Use appropriate lifting equipment and adopt
all safety precautions needed for moving and
handling the equipment.
A crane or forklift is recommended for
unloading, assembly, and installation of the
collector.
Location must be clear of all obstructions,
such as utility lines or roof overhang.
Ensure weight of oil-laden unit plus weight
of required materials and equipment will be
adequately supported. Failure to comply may
result in personal injury and/or property damage.
Top View
45°
Front View
60°
Isometric View
customer-supplied
chain or cable
eye bolt
Ceiling Mount Installation, WSO 20 shown
1. Verify that the ceiling attachment points can bear the
live load.
2. Use properly sized cable or chain to attach to each
of the four WSO attachment lugs (WSO 25-1) or
eyebolts (WSO 20) to suspend the unit from the
ceiling.
3. To prevent sway, position the chain or cable to form
a 60 degree angle to the top of the unit and a 45
degree angle along the sides.

WSO Mist Collector,WSO 20, 25-1, 25-2, and 25-3
12
P-Trap Installation
Ensure collected material
properly flows through the
P-Trap. The P-Trap dimensions should
accommodate a column of coolant greater
than the static capacity of the fan to avoid
coolant pooling in the collector and potentially
causing property damage.
1. Install the P-Trap as shown in P-Trap Installation.
2. Position the P-Trap outlet to the proper location and
tighten the union.
3. Plumb the P-Trap to a receptacle or install a return
line back to the machine center.
4. Fill P-Trap before starting unit.
Note: The characteristics of some machining fluids
change with time, use, and exposure to air.
Check the condition of the collected fluid
before re-using.
Inlet Collar Installation
(WSO 20 and 25-1)
1. Install the inlet collar to the desired inlet location
using the supplied sealant and hardware.
2. For single-inlet configurations, install the inlet
blank to the inlet opposite the inlet collar using the
supplied sealant and hardware.
(WSO 25-2 and 25-3)
1. Refer to the Specification Control Drawing to get the
dimensions and bolt pattern of the inlet. Typically,
a rectangle-to-round transition, custom to your
particular installation, is obtained from the ducting
supplier. Install the rectangle-to-round transition to
the desired inlet location using the supplied sealant
and hardware.
2. For single-inlet configurations, install the inlet
blank to the inlet opposite the inlet collar using the
supplied sealant and hardware.
hopper
maximum
fill level
union
pipe plug
NPT pipe
P-Trap Installation
sealant
inlet collar
Inlet Collar Installation, WSO 25-1 shown
NOTICE

13
Donaldson Company, Inc.
Electrical Connection
(WSO 20, 25-1, and Powered WSO 25-2,
25-3)
Electrical service or
maintenance work must be
performed by a qualified electrician and
comply with all applicable national and local
codes.
Turn power off and lock out electrical
power sources before performing service or
maintenance work.
Do not install in classified hazardous
atmospheres without an enclosure rated for
the application.
WSO mist collectors must be equipped with a customer-
supplied safety disconnect with short circuit protection,
contactors, and overload protection. Complete the
wiring as shown in Motor Starter Wiring.
1FU
2FU
3FU
1M 1OL
1T2
1T3
fan
motor
Disconnect
L1
L2
L3
1T1
1L1
1L2
1L3
208/230/460/575/60/3
Motor Starter Wiring
Motor Starter Control Box
Mount the motor starter control box in a convenient
location. For the WSO 20 and 25-1, an electrical
knockout, sized for 1/2-in fittings, is provided on the left-
hand side of the blower cabinet. Increase knockout size
using a drill as required.
1. Using the wiring diagram supplied inside the control
box and the instructions on the motor decal, make
the connections to the blower motor.
Note: If the unit is supplied with an optional
junction box, wire the motor starter to the
terminal strip located inside the junction box
according to the wiring diagram supplied
with the junction box.
2. Turn the blower motor ON then OFF and check for
proper rotation: clockwise for WSO 25-1, powered
WSO 25-2 and 25-3 and see rotation arrow on the
motor’s mounting plate for WSO 20.
To reverse rotation, three-phase power supply: Turn
electrical power OFF at source, properly lock-out
power, and switch any two leads on the output-side
of the blower motor starter.
Do not interchange a power lead
with the ground wire. Severe
personal injury or equipment damage may
result.
Do not look into fan outlet to determine
rotation. View the fan rotation from the back of
the motor.
Check that the exhaust plenum is free of tools
or debris before checking blower/fan rotation.
Stand clear of exhaust to avoid personal injury.
3. Ground cabinet according to local electric codes.

WSO Mist Collector,WSO 20, 25-1, 25-2, and 25-3
14
Preliminary Start-Up Check
Instruct all personnel on safe use and maintenance
procedures.
Electrical work during
installation must be performed
by a qualified electrician and comply with all
applicable national and local codes.
Turn power off and lock out electrical
power sources before performing service or
maintenance work.
Turn compressed air supply OFF and bleed
lines before performing service or maintenance
work
Check that the collector is clear and free of all
debris before starting.
Do not install in classified hazardous
atmospheres without an enclosure rated for
the application.
Optional fans over 600 lbs must be
independently supported.
1. Check all electrical connections for tightness and
contact.
2. Motor and fan should be wired for clockwise rotation
when viewed from the back of the motor.
To reverse rotation, three-phase power supply:
Turn electrical power OFF at source and switch any
two leads on the motor junction box.
Do not interchange a power lead
with the ground wire. Severe
damage or personal injury may result.
3. Check that all filters are properly installed.
4. All access panels should be sealed and secure.
5. Check that exhaust damper is set to the fully-closed
position.
6. Check and remove all loose items in or near the inlet
and outlet of the unit.
7. Check that all remote controls and solenoid
enclosures (if applicable) are properly wired and all
service switches are in the OFF position.
8. Check that hopper discharge is open and the storage
container is sealed, if equipped.
9. Fill P-Trap if equipped, or close faucet valve on drain
collection container if used.
10. Check that all optional accessories are installed
properly and secured.
11. Turn blower fan motor ON.
Do not look into fan outlet to
determine rotation. View the fan
rotation through the back of the motor.
Check that the exhaust plenum is free of tools
or debris before checking blower/fan rotation.
Stand clear of exhaust to avoid personal injury.
12. Adjust airflow with the exhaust damper.
Excess airflow can shorten filter
life, cause electrical system
failure, and blower motor failure.
NOTICE

15
Donaldson Company, Inc.
Maintenance Information
Instruct all personnel on safe use and maintenance
procedures.
Use proper equipment and adopt
all safety precautions needed
for servicing equipment. Electrical service
or maintenance work must be performed by
a qualified electrician and comply with all
applicable national and local codes.
Turn power off and lock out electrical
power sources before performing service or
maintenance work.
Do not install in classified hazardous
atmospheres without an enclosure rated for
the application.
Operational Checklist
1. Monitor the physical condition of the collector and
repair or replace any damaged components.
Routine inspections will minimize downtime and
maintain optimum system performance. This
is particularly important on continuous-duty
applications.
Periodically check the compressed air components
and replace compressed air filters.
Drain moisture following the manufacturer’s
instructions. With the compressed air supply ON,
check the cleaning valves, solenoid valves, and
tubing for leaks. Replace as necessary.
2. Monitor pressure drop across filters.
Abnormal changes in pressure drop indicate a
change in operating conditions and possibly a fault
to be corrected. For example, prolonged lack of
compressed air will cause an excess build-up of dust
on the filters resulting in increased pressure drop.
Cleaning off-line with no flow usually restores the
filters to normal pressure drop.
3. Monitor exhaust.
4. Monitor hopper drainage. If slow or stopped, check
hopper for obstructions and clean as necessary.
5. Check that the P-Trap is full. Refill if low or dry.
6. If equipped with a HEPA or 95% DOP, monitor
pressure drop across after filter. Initial final filter
pressure drop is approximately 1-2”wg. Replace the
final filter when the gauge reads 3.5 to 4.0”wg. Do
not attempt to clean or wash the final filter. Replace
only.
Do not operate the unit without
the first- or primary-stage filter
in place. Significant reduction in final filter life
can result.
Filter Removal and Installation
Use proper safety and protective
equipment when removing
contaminants and filters.
Dirty filters may be heavier than they appear.
Use care when removing filters to avoid
personal injury.
First Stage Filter Cleaning and Installation
Remove the first stage filter through the lower access
door. Clean the first-stage screen by tapping it gently
over an appropriate waste container. If further cleaning
is required, wash in an appropriate wash tank. To clean
the first-stage filter, soak in an appropriate wash tank,
rinse, dry, and re-install.
High temperature, steam-
cleaning methods should not be
used with the polypropylene filters due to the
temperature limitations.
Do not operate the WSO mist collector without
the first-stage filter in place. Significant
reduction in primary filter life can result.
NOTICE
NOTICE

WSO Mist Collector,WSO 20, 25-1, 25-2, and 25-3
16
Primary Filter Installation
Note: With the unit’s airflow off, allow mist-laden, wet
filter to drain into the inlet plenum for at least 15
minutes prior to removal.
1. Remove the filter cartridge by pulling the filter
retention lever down to a horizontal position. Remove
cartridge from unit and dispose of properly for the
materials collected.
Note: A large plastic garbage bag placed over the top
of the used filter allows cleaner filter change out.
The filter can be tipped forward and out of the
unit while the bag is pulled up over the bottom of
the cartridge.
2. Place new filter on the filter retention platform,
gasket side up. Slide filter back as far as it will go.
Note: The primary filter must be replaced. Do not wash.
3. Lift the filter retention lever up and close access
door.
primary
filter cartridge
filter retention lever
pull down
Primary Filter Replacement, WSO 25-1 shown

17
Donaldson Company, Inc.
Final Filter Installation (WSO 20 and 25-1)
Note: The final filter must be replaced. Do not wash.
1. Unlatch the final filter on top of the unit.
2. Remove the filter and dispose of properly for the
materials collected.
Dirty filters may be heavier than
they appear. Provide a support
platform or have two people, one on each side
of the filter and pull the filter out.
3. Install the replacement filter gasket-side down.
4. Latch the new filter in place.
NOTICE
Final Filter Installation (WSO 25-2 and 25-3)
Note: The final filter must be replaced. Do not wash.
1. Open the final filter access door and lower the
retention handles to release the filter.
2. Remove the filter and dispose of properly for the
materials collected.
Dirty filters may be heavier than
they appear. Provide a support
platform or have two people, one on each side
of the filter and pull the filter out.
3. Install the replacement filter gasket-side up.
4. Seal the filter in place by lifting the retention handles
to the upright position.
NOTICE
final filter
(gasket-side
down)
latch
Final Filter Installation, WSO 25-1 shown
final filter
(gasket-side up)
retention
handle
Final Filter Installation, Powered WSO 25-2 shown