Desa D20N User manual

IMPORTANT:Readandunderstandthismanualbeforeassembling,start-
ing or servicing heater. Improper use of heater can cause serious injury.
Keep this manual for future reference.
Models: D20N, D30N, and D44N
PORTABLE
FORCED
AIR HEATERS
OWNER’S MANUAL

2
105843
PORTABLE FORCED AIR HEATERS
D20N, D30N AND D44N MODELS
SAFETY
INFORMATION
WARNINGS
IMPORTANT: Read this Owner’s
Manual carefully and completely
before trying to assemble, oper-
ate, or service this heater. Im-
proper use of this heater can
causeseriousinjuryordeathfrom
burns, fire, explosion, electrical
shock, and carbon monoxide
poisoning.
DANGER: Carbon monoxide
poisoning may lead to death!
Carbon Monoxide Poisoning: Early signs
ofcarbonmonoxidepoisoningresemblethe
flu, with headaches, dizziness, and/or nau-
sea. If you have these signs, the heater may
not be working properly. Get fresh air at
once! Have heater serviced. Some people
are more affected by carbon monoxide than
others.Theseincludepregnantwomen,per-
sons with heart or lung disease or anemia,
those under the influence of alcohol, and
those at high altitudes.
Make certain you read and understand all
warnings.Keepthismanualforreference.It
isyourguidetosafeandproperoperationof
this heater.
• Use only kerosene or No. 1 fuel oil to
avoid risk of fire or explosion. Never use
gasoline,naphtha, paintthinners, alcohol,
or other highly flammable fuels.
• Fueling
a) Personnel involved with fueling shall
be qualified and thoroughly familiar
with the manufacturer's instructions
and applicable regulations regarding
the safe fueling of heating units.
b) Only the type of fuel specified on the
heater's data plate shall be used.
c) All flame, including the pilot light, if
any, shall be extinguished and the
heater allowed to cool, prior to
fueling.
d) During fueling,all fuel linesand fuel-
lineconnections shallbe inspectedfor
leaks. Any leaks shall be repaired
priorto returningthe heaterto service.
e) At no time shall more than one day's
supply of heater fuel be stored inside
abuilding in the vicinity of the heater.
Bulk fuel storage shall be outside the
structure.
f) All fuel storage shall be located a
minimum of 762cm (25 feet) from
heaters, torches, welding equipment,
and similar sources of ignition
(exception: the fuel reservoir integral
with the heater unit).
g) Whenever possible, fuel storage shall
be confined to areas where floor
penetrationsdo not permitfuel to drip
onto or be ignited by a fire at lower
elevation.
h) Fuel storage shall be in accordance
withthe authority havingjurisdiction.
• Never use heater where gasoline, paint
thinner,or otherhighly flammablevapors
are present.
• Follow all local ordinances and codes
when using heater.
• Heaters used in the vicinity of tarpaulins,
canvas, or similar enclosure materials
shall be located a safe distance from such
materials. The recommended minimum
safe distance is 304.8cm (10 feet). It is
further recommended that these enclo-
sure materials be of a fire retardant na-
ture. These enclosure materials shall be
securely fastened to prevent them from
igniting or from upsetting the heater due
to wind action.
• Use only in well-vented areas. Before us-
ing heater, provide at least a 2800 square
cm (three-square-foot) opening of fresh,
outside air for each 100,000 Btu/Hr of
rating.
• Use only in places free of flammable va-
pors or high dust content.
• Use only the electrical voltage and fre-
quency specified on model plate.
• Use only a three-prong, grounded exten-
sion cord.
• Minimum heater clearances from com-
bustibles:
Outlet: 250 cm (8 Ft.)
Sides, Top, and Rear: 125 cm (4 Ft.)
• Locate heater on a stable and level sur-
face if heater is hot or running or a fire
may occur.
• When moving or storing heater, keep
heater in a level position or fuel spillage
may occur.
• Keep children and animals away from
heater.
• Unplug heater when not in use.
• When used with thermostat, heater may
start anytime.
• Never use heater in living or sleeping
areas.
• Never block air inlet (rear) or air outlet
(front) of heater.
• Never move, handle, refuel, or service a
hot, operating, or plugged-in heater.
• Never attach duct work to front or rear
of heater.

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105843
OWNER’S MANUAL
Side Cover
Lower
Shell
Fuel Cap
Hot Air Outlet
Upper Shell
Power Cord
Fuel Tank
Fan Guard
Lower Shell
Side Cover
Fuel Tank
Upper Shell
Hot Air Outlet
Fan Guard
Air Filter
End Cover
Fuel Cap
Power
Cord
ON/OFF Switch
with Light
ON/OFF Switch
with Light
PRODUCT
IDENTIFICATION
Figure 1 - D20N Model
Figure 2 - D30N and D44N Models
UNPACKING
1. Remove all packing items applied to
heater for shipment.
2. Remove all items from carton.
3. Check items for any shipping damage.
If heater is damaged, promptly inform
dealer where you bought heater.
FUELS
WARNING:Useonlykerosene
orNo.1fueloiltoavoidriskoffire
orexplosion.Never usegasoline,
naphtha, paint thinners, alcohol
or other highly flammable fuels.
Donotuseheavyfuelssuchas No. 2fueloil
or No. 2 Diesel. Using heavy fuels will
result in:
• clogged fuel filter and nozzle
• use of non-toxic anti-icer in fuel during
very cold weather
IMPORTANT: Use a KEROSENE ONLY
container.Besurestoragecontainerisclean.
Foreign matter such as rust, dirt, or water
will cause the flame-out control to shut
down heater. Foreign matter may also re-
quire you to clean fuel system often.

4
105843
PORTABLE FORCED AIR HEATERS
D20N, D30N AND D44N MODELS
ASSEMBLY
Thesemodelsarefurnishedwithwheelsand
handles.Wheels,handles,andthemounting
hardware are found in the shipping carton.
TOOLS NEEDED
• Medium Phillips Screwdriver
• 3/8" Open orAdjustable Wrench
• Hammer
1. Slide axle through wheel support
frame. Install wheels on axle.
IMPORTANT: When installing wheels,
point extended hub of wheels toward
wheel support frame (see Figure 3).
2. Place cap nuts on axle ends. Gently tap
with hammer to secure.
3. Place heater on wheel support frame.
For D20N model, make sure outlet end
(front) of heater is over wheels. For
D30Nand D44N models,make sure air
inletend (rear) ofheater is overwheels.
Line up holes on fuel tank flange with
holes on wheel support frame.
4. For D20N model, place rear handle on
top of fuel tank flange. For D30N and
D44N models, place front handle and
rear handle on top of fuel tank flange.
Insert screws through handle(s), fuel
tank flange, and wheel support frame.
Attach nut finger tight after each screw
is inserted.
5. After all screws are inserted, tighten
nuts firmly.
Figure 3 - Wheel and Handle Assembly
Handle
Sleeve Cap Screw
Hot Air
Outlet
Air
Inlet
Wheel Support
Frame
Wheel
Fuel
Tank
Flange
Cap Nut
Nut Extended
Hub
Axle
Screw
Wheel
Support
Frame
Wheel
Cap Nut
Nut
Extended
Hub
Front
Handle
Axle
Rear
Handle
Air
Inlet
Fuel
Tank
Flange
Hot Air
Outlet
D20N Model
VENTILATION
WARNING: Follow the mini-
mumfresh,outsideairventilation
requirements.Ifproperfresh,out-
sideairventilationisnotprovided,
carbon monoxide poisoning can
occur. Provide proper fresh, out-
sideairventilationbeforerunning
heater.
D30N and D44N Models
Provide a fresh air opening of at least 2800
square cm (three square feet) for each
100,000 Btu/Hr rating. Provide extra fresh
air if more heaters are being used.
Example: A150,000Btu/Hrheaterrequires
one of the following:
• atwo-car garagedoor [4.9m (16ft.) open-
ing] raised 9 cm (3.5 inches)
• a single-car garage door [2.75 m (9 ft.)
opening] raised 15.25 cm (6 inches)
• two, 76 cm (30 inch) windows raised 28
cm (11 inches)

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105843
OWNER’S MANUAL
OPERATION
WARNING: Review and un-
derstand the warnings in the
Safety Information section, page
2. They are needed to safely op-
erate this heater. Follow all local
codes when using this heater.
TO START HEATER
1. Follow all ventilation and safety infor-
mation.
2. Fill fuel tank with kerosene or No. 1
fuel oil.
3. Attach fuel cap.
4. Plug powercord of heaterinto standard
230 volt/50 hertz, grounded (earthed)
outlet. Use an extension cord if needed.
Use only a three-prong, grounded
(earthed) extension cord.
Figure 5 - ON/OFF Switch, D20N Model
Figure 6 - ON/OFF Switch, D30N and
D44N Models
THEORY OF
OPERATION
The Fuel System: The air pump forces air
through the air line. The air is then pushed
through the burner head nozzle. This air
causes fuel to lift from the tank. A fine mist
offuelissprayedintothecombustioncham-
ber.
The Air System: The motor turns the fan.
The fan pushes air into and around the
combustion chamber. This air is heated and
provides a stream of clean, hot air.
The Ignition System: The ignition control
assembly provides power to the ignitor.
This ignites the fuel/air mixture in the com-
bustion chamber.
The Flame-Out Control System: Thissys-
tem causes the heater to shut down if the
flame goes out.
Extension Cord Wire Size
Requirements
Up to 30.5 meters (100 feet) long, use 1.0
mm2 (16 AWG) conductor
30.6to 61 meters(101 to200feet) long,use
1.5 mm2 (14 AWG) conductor
Push ON/OFF switch to ON (|) position and
heater should start in 5 seconds. If ON/OFF
switch light does not come on or heater does
notstart,seeTroubleshooting(pages6and7).
TO STOP HEATER
1. Push ON/OFF switch to OFF (O)
position.
TO RESET HEATER
1. Push ON/OFF switch to OFF (O) posi-
tion and wait 10 seconds (2 minutes if
heater has been running).
2. Repeat steps under To Start Heater.
Figure 4 - Cross Section Operational View
|
O
ON/OFF Switch with Light
|
O
ON/OFF Switch
with Light
Clean
Heated
Air Out
Fuel
Filter Air Line
To Burner
Air
Output
Filter
Air Pump
Air Intake
Filter
Cool
Air
In
Fan
Combustion ChamberIgnitor Motor
Ignition Control
Assembly
Air For Fuel System Air For Combustion
And Heating Fuel
Nozzle
Fuel
Tank

6
105843
PORTABLE FORCED AIR HEATERS
D20N, D30N AND D44N MODELS
STORING,
TRANSPORTING,
OR SHIPPING
Note: If shipping, transport companies re-
quire fuel tanks to be empty.
1. Drain fuel tank.
Note: Some models have drain plug on
underside of fuel tank. If so, remove
drain plug to drain all fuel. If heater
does not have drain plug, drain fuel
through fuel cap opening. Be sure all
fuel is removed.
2. Replace drain plug if provided.
3. If any debris is noted in old fuel, add 1
or 2 quarts of clean kerosene to tank,
stir, and drain again. This will prevent
excess debris from clogging filters dur-
ing future use.
4. Replace fuel cap or drain plug. Prop-
erlydispose ofold anddirty fuel. Check
with local automotive service stations
that recycle oil.
5. If storing, store heater in dry place.
Make sure storage place is free of dust
and corrosive fumes.
IMPORTANT: Do not store kerosene over
summer months for use during next heating
season.Usingoldfuelcoulddamageheater.
PREVENTATIVE
MAINTENANCE
SCHEDULE
How To
SeeStoring,Transporting, orShip-
ping
SeeAirOutput,AirIntake,andLint
Filters, page 10
SeeAirOutput,AirIntake,andLint
Filters, page 10
See Fuel Filter, page 8
See Fan, page 13
WARNING: Never service heater
while it is plugged in, operating, or hot.
Severe burns and electrical shock can
occur.
Item
Fuel tank
Air output and
lint filters
Air intake filter
Fuel filter
Ignitor
Fan blades
Motor
How Often
Flush every 150-200 hours of
operation or as needed
Replace every 500 hours of
operation or once a year
Wash and dry with soap and
water every 500 hours of op-
eration or as needed
Clean twice a heating season
or as needed
No maintenance required
Clean every season or as
needed
Notrequired/permanently lu-
bricated
REMEDY
1. Check all electrical connections. See
Wiring Diagram, page 21
2. See Ignition Control Assembly, page 13
3. If fan does not turn freely, see Pump
Rotor, page 12
4. Replace ignition control assembly
5. Replace motor
POSSIBLE CAUSE
1. Bad electricalconnection betweenmotor
andignition control assemblyor ignition
control assembly and power cord
2. Blown fuse on ignition control assembly
3. Binding pump rotor
4. Defective ignition control assembly
5. Defective motor
TROUBLESHOOTING WARNING: Never service heater while it is plugged in, operating, or
hot. Severe burns and electrical shock can occur.
WARNING: High voltage!
FAULT CONDITION
Motordoesnotstartfivesecondsafterheater
ispluggedin(ON/OFFswitchlightremains
on)
ATTENTION: The ignition control has built-in protection against current overloads. Use
the light in the ON/OFF switch to troubleshoot the fault condition.

7
105843
OWNER’S MANUAL
REMEDY
1. Fill tank with kerosene
2. See Pump PressureAdjustment, page 10
3. See Fuel Filter, page 8
4. See Nozzle Assembly, page 11
5. Drain and flush fuel tank with clean
kerosene. See Storing, Transporting, or
Shipping, page 6
6. Check electricalconnections. SeeWiring
Diagram, page 21
7. Replace ignitor, see page 9
8. Replace ignition control assembly
1. See Pump PressureAdjustment, page 10
2. See Air Output, Air Intake, and Lint
Filters, page 10
3. See Fuel Filter, page 8
4. See Nozzle Assembly, page 11
5. Make sure photocell boot is properly
seated in bracket
6. Clean photocell lens
7. Check electricalconnections. SeeWiring
Diagram, page 21
8. Replace photocell
9. Replace ignition control assembly
1. Verify that power cord is plugged into
an electrical outlet and that the circuit
breaker in the electral panel is reset
2. Check electricalwiring andconnections.
See Wiring Diagram, page 21
3. Check ignitor wiring. If no problems are
found, replace ignitor (see page 9)
1. Check motor wiring. If no problems are
found, replace motor
POSSIBLE CAUSE
1. No fuel in tank
2. Pump pressure incorrect
3. Dirty fuel filter
4. Obstruction in nozzle assembly
5. Water in fuel tank
6. Bad electrical connection between
ignitor and ignition control assembly
7. Defective ignitor
8. Defective ignition control assembly
1. Pump pressure incorrect
2. Dirty air intake, air output, and/or lint
filter
3. Dirty fuel filter
4. Obstruction in nozzle assembly
5. Photocell assembly not properly
installed (not seeing the flame)
6. Dirty photocell lens
7. Bad electrical connection between
photocell and ignition control assembly
8. Defective photocell
9. Defective ignition control assembly
1. No power to heater
2. Bad electrical connections
3. Electrical short in ignitor
1. Electrical short in motor
TROUBLESHOOTING
Continued
WARNING: High voltage!
FAULT CONDITION
Motor starts and runs but heater does not
ignite (ON/OFF switch light remains on)
Heaterignitesbutignitioncontrolassembly
shuts heater off after a short period of time
(ON/OFF switch light remains on)
ON/OFF switch light does not come on
when switch is turned to the ON(I) position
and heater does not start
ON/OFFswitchlightcomesonwhenswitch
is turned to the ON(I) Position but turns off
after five seconds
WARNING: High voltage!
WARNING: High voltage!
WARNING: High voltage!

8
105843
PORTABLE FORCED AIR HEATERS
D20N, D30N AND D44N MODELS
Figure 9 - Fuel Filter Removal, D20N Model
UPPER SHELL REMOVAL
1. Remove screwsand lockwashers along
each side of heater using 5/16" nut-
driver. These screws attach upper and
lower shells together.
2. Lift upper shell off.
3. Remove fan guard.
FUEL FILTER
(D20N Model)
1. Remove side cover screws using 5/16"
nut-driver.
2. Remove side cover.
3. Pull rubber fuel line off fuel filter neck.
4. Carefully prybushing andfuel filter out
of fuel tank.
5. Wash fuel filter with clean fuel and re-
place in tank.
6. Attach rubber fuel line to fuel filter
neck.
7. Replace side cover.
FUEL FILTER
(D30N and D44N Models)
1. Remove side cover screws using 5/16"
nut-driver.
2. Remove side cover.
3. Pull upper fuel line off fuel filter neck.
4. Carefully pry bushing, lower fuel line,
and fuel filter out of fuel tank.
5. Wash fuel filter with clean fuel and re-
place in tank.
6. Attach upperfuel lineto fuelfilter neck.
7. Replace side cover.
SERVICE
PROCEDURES
WARNING: Never service
heater while it is plugged in, op-
erating,orhot.Severeburnsand
electrical shock can occur.
Upper Shell
Fan
Guard
Figure 7 - Upper Shell Removal, D20N
Model Figure 8 - Upper Shell Removal, D30N
and D44N Models
Fuel Filter
Side Cover
Fuel Line
Fan
Guard
Upper
Shell
Fuel Filter, Bushing,
and Lower Fuel Line
Upper Fuel
Line
Side Cover
Figure 10 - Fuel Filter Removal, D30N and D44N Models

9
105843
OWNER’S MANUAL
SERVICE
PROCEDURES
Continued
Continued
IGNITOR
1. Remove upper shell and fan guard (see
page 8).
2. Remove fan (see page 13).
3. Remove 4 side cover screws with a
5/16" nut driver. Remove side cover
(see Figure 9 or 10, page 8).
4. Disconnect ignitor wires (gray) from
ignition control assembly (see Figure
11). Pull the ignitor wires up through
the hole in the lower shell.
5. Disconnect fuel line hose and air line
hose.Removephotocell fromphotocell
bracket (see Figure 11).
Combustion
Chamber
Photocell
Bracket
Photocell
Assembly
Air
Line
Hose
Fuel
Line
Hose
Combustion
Chamber
Photocell
Bracket
Ignitor
Wires
Ignitor
Nozzle
Adapter
Bracket
Ignition
Control
Assembly
Side Cover
Figure 11 - Disconnecting Ignitor Wires
from Ignition Control Assembly
Ignitor
Ignitor Screw/Washer
Assembly
Nozzle
Adapter
Bracket
Nozzle Adapter
Bracket Opening
Ignitor
Element
Figure 12 - Ignitor Replacement
CAUTION:Donotbendorstrike
ignitor element. Handle with care.
6. Remove combustion chamber. Stand
combustion chamber on end with
nozzle adapter bracket on top (see Fig-
ure 12).
7. Remove ignitor screw with a 1/4" nut
driver. Carefully remove ignitor from
nozzle adapter bracket.
10. Replace combustion chamber.
11. Route the ignitor wires back down
through the hole in the lower shell.
Connect wires to the ignition control
assembly.
12. Replace side cover (see Figure 9 or 10,
page 8).
13. Connect and route fuel line hose and
air line hose to burner head. See Fuel
and Air Line Replacement and Proper
Routing, page 11.
14. Replace photocell in photocell
bracket. Route wires as shown in Fig-
ures 17, 18, and 19 page 11.
15. Replace fan (see page 13).
16. Replace fan guard and upper shell (see
page 8).
8. Carefully remove replacement ignitor
from styrofoam packing.
9. Carefully guide ignitor into opening in
nozzle adapter bracket. Do not strike
ignitor element. Attach ignitor to
nozzle adapter bracket with screw us-
ing a 1/4" nut driver (see Figure 12).
Torque 8 to 15 in. lbs. Do not over
torque.

10
105843
PORTABLE FORCED AIR HEATERS
D20N, D30N AND D44N MODELS
AIR OUTPUT, AIR INTAKE,
AND LINT FILTERS
1. Remove upper shell (see page 8).
2. Remove filter end cover screws using
5/16" nut-driver.
3. Remove filter end cover.
4. Replace air output and lint filters.
5. Wash or replace air intake filter (see
Preventative Maintenance Schedule,
page 6).
6. Replace filter end cover.
7. Replace fan guard and upper shell.
IMPORTANT: Do not oil filters
PUMP PRESSURE
ADJUSTMENT
1. Remove pressuregauge plugfrom filter
end cover.
2. Install accessory pressure gauge (part
number HA1180).
3. Start heater (see Operation, page 5).
Allow motor to reach full speed.
4. Adjust pressure. Turn relief valve to
right to increase pressure. Turn relief
valve to left to decrease pressure. See
specifications below for correct pres-
sure for each model.
5. Remove pressure gauge. Replace pres-
sure gauge plug in filter end cover.
Figure 13 - Air Output, Air Intake, and Lint Filters, D20N Model
Figure 15 - Pressure Gauge Plug Removal
Pressure
Gauge
Plug
Pressure
Gauge
Figure 16 - Adjusting Pump Pressure
Pump
Pressure
Model (PSI/Bar)
D20N 4.7/0.324
D30N 4.9/0.338
D44N 5.5/0.380
(D20N Model Shown)
Relief
Valve
SERVICE
PROCEDURES
Continued
Air Intake Filter
Lint Filter
Filter End
Cover
Air Output
Filter
Fan Guard
Air Intake Filter
Filter End
Cover
Lint Filter Air Output
Filter
Figure 14 - Air Output, Air Intake, and Lint Filters, D30N and D44N Models
Fan Guard

11
105843
OWNER’S MANUAL
Continued
SERVICE
PROCEDURES
Continued
Fuel Line
Hose
Nozzle/
Adapter
Assembly
Combustion
Chamber
Air Line
Hose
Figure 18 - Removing Air and Fuel Line
Hoses (D30N Model Only)
Nozzle/
Adapter
Assembly
Combustion
Chamber
Figure 20 - Removing Nozzle/Adapter
Assembly
Nozzle Face
Nozzle
Nozzle
Seal
Nozzle
Adapter
Air Line
Fitting Fuel Line Fitting
Figure 21 - Nozzle and Nozzle Adapter
NOZZLE ASSEMBLY
1. Remove upper shell (see page 8).
2. Remove fan (see page 13).
3. Removefuelandairlinehosesfromnozzle
assembly (see Figure 17, 18, or 19).
4. Turn nozzle assembly 1/4 turn to left
and pull toward motor to remove (see
Figure 20).
5. Place plastic hex-body into vise and
lightly tighten.
6. Carefully remove nozzle from the
nozzle adapter using 5/8" socket
wrench (see Figure 21).
7. Blow compressed air through face of
nozzle. This will free any dirt in nozzle
area.
8. Inspect nozzle seal for damage.
9. Replace nozzle into nozzle adapter un-
til nozzle seats. Tighten 1/3 turn more
using 5/8" socket wrench (40-45 inch-
pounds). See Figure 21.
10. Attach nozzle assembly to burnerstrap.
11. Attach fuel and airline hoses to nozzle
assembly. See Fuel and Airline Re-
placement and Proper Routing.
12. Replace fan (see page 13).
13. Replace fan guard and upper shell (see
page 8).
Burner
Strap
Continued
Photocell Bracket
Fuel Line
Hose
Nozzle/
Adapter
Assembly
Combustion
Chamber
Figure 19 - Removing Air and Fuel Line
Hoses (D44N Model Only)
Burner
Strap
Photocell
Bracket
FUEL AND AIR LINE
REPLACEMENT AND
PROPER ROUTING
1. Remove upper shell (see page 8).
2. Remove side cover screws using 5/16"
nut driver.
3. Remove side cover.
4. Inspect fueland airline hosesfor cracks
and/or holes. If fuel line hose is dam-
aged, disconnect from nozzle adapter
(see Figure 17, 18, or 19) and from fuel
filter (see page 8). If air line hose is
damaged, disconnect from nozzle
adapter (see Figure 17, 18, or 19) and
from barb fitting on pump end cover
(see Figure 22).
5. Install new air and/or fuel line. Attach
one end of air line hose to barb fitting
on pump end cover (see Figure 22) and
the other end to nozzle adapter (see
Figure 17, 18, or 19). Attach one end
of fuel line hose to fuel filter (see page
8) and the other end to nozzle adapter
(see Figure 17, 18,or 19).
Route air and fuel line approximately
as shown. For D20N model heater, see
Figure 17. For D30N model heater, see
Figure 18. For D44N model heater, see
Figure 19.
Note: Hoses arenot tobe touchingpho-
tocell bracket.
6. Replace side cover.
7. Replace upper shell and fan guard (see
page 8).
Figure 22 - Air Hose to Barb FItting
Barb Fitting
Air Hose
Pump End Cover
Air Line
Hose
Fuel Line
Hose
Nozzle/
Adapter
Assembly
Combustion
Chamber
Figure 17 - Removing Air and Fuel Line
Hoses (D20N Model Only)
Burner
Strap
Photocell
Bracket
Air Line
Hose

12
105843
PORTABLE FORCED AIR HEATERS
D20N, D30N AND D44N MODELS
PUMP ROTOR
(Procedure if Rotor is Binding)
1. Remove upper shell (see page 8).
2. Remove filter end cover screws using
5/16" nut-driver.
3. Remove filter end cover and air filters.
4. Remove pumpplate screwsusing 5/16"
nut-driver.
5. Remove pump plate.
6. Remove rotor, insert, and blades.
7. Check for debris in pump. If debris is
found, blow out with compressed air.
8. Install insert and rotor.
9. Check gap on rotor.Adjust to .076/.101
mm (.003"/.004") if needed (see Fig-
ure 25).
Note: Rotate rotor one full turn to ensure
the gap is .076/.101 mm (.003"/.004") at
tightest position. Adjust if needed.
10. Install blades, pump plate, air filters,
and filter end cover.
11. Replace fan guard and upper shell.
12. Adjust pump pressure (see page 10).
Note: If rotor is still binding, proceed as
follows.
13. Perform steps 1 through 6 above.
14. Place fine grade sandpaper (600 grit)
on flat surface. Sand rotor lightly in
“figure 8” motion four times (see Fig-
ure 26).
15. Reinstall insert and rotor.
16. Perform steps 10 through 12 above.
Figure 23 - Rotor Location, D20N Model
Figure 24 - Rotor Location, D30N and D44N Models
Insert
Blade
Rotor
Pump
Plate Air Intake Filter
Air Output
Filter
Pump
Plate
Insert Rotor
Blade
Filter End
Cover
Air
Intake
Filter
Air Output
Filter
Fan Guard
Fan Guard
Filter End
Cover
Figure 26 - Sanding Rotor
Figure25-GapAdjustingScrewLocations
SERVICE
PROCEDURES
Continued
Gap Adjusting
Screw
Gap Adjusting
Screw
Blade .076/.101 mm (.003"/.004") Gap
Measured With Feeler Gauge
Rotor Sandpaper

13
105843
OWNER’S MANUAL
FAN
IMPORTANT: Remove fan from motor
shaft before removing motor from heater.
The weight of the motor resting on the fan
could damage the fan pitch.
1. Remove upper shell (see page 8).
2. Use 1/8" allen wrench to loosen set-
screw which holds fan to motor shaft.
3. Slip fan off motor shaft.
4. Clean fan using a soft cloth moistened
with kerosene or solvent.
5. Dry fan thoroughly.
6. Replace fan on motor shaft. Place fan
hub flush with end of motor shaft (see
Figure 28).
7. Place setscrew on flat of shaft.Tighten
setscrew firmly (40-50 inch-pounds/
4.5-5.6 n-m).
8. Replace fan guard and upper shell.
Motor
Shaft
Setscrew
Figure27-Fan,MotorShaft,andSetscrew
Location
Motor
Shaft
Fan
Setscrew
Figure 28 - Fan Cross Section
Fan
Flush
SERVICE
PROCEDURES
Continued
Unacceptable Acceptable
WARNING: Unplug heater
before servicing.
Remove Old Assembly
1. Using the 5/16" nut driver or socket
wrench, remove the four side cover
screws (see Figure 29).
2. Disconnect the nine wires from the
ignition control assembly.
3. Usingneedlenosepliers,squeezethetab
on the printed circuit board support and
lift up on the edge of the ignition control
assembly(seeFigure30).Repeatthisfor
the other four printed circuit board sup-
ports then remove the assembly.
CAUTION: Ignition control
assemblycontainselectrostatic
components.Handletheassem-
bly by the edges of the printed
circuit board. Do not touch any
of the quick connect terminals
or electronic components.
Figure 29 - Removing Cover
Side
Cover
Figure 30 - Removing Circuit Board
Side Cover
Ignition
Control
Assembly Printed Circuit
Board Supports (5)
Installing the New Assembly
1. Align the five holes in the assembly
withthe five printedcircuit board sup-
ports in the side cover.
2. Holding the assembly by the edges of
the printed circuit board, apply down-
ward pressure until all five tabs on the
printedcircuitboardsupportsspringlock
intoplace.Pullupon assembly toverify
this (see Figure 31).
3. Connect the nine wire leads to the
ignition control assembly as shown
in the wiring diagram on page 21.
Figure 31 - Attaching Circuit Board to
Tabs
CAUTION: Double check
connections. Connecting igni-
tion control assembly wrong
could result in damage to the
ignition control assembly and/
or other components in the
heater assembly.
4. Using the 5/16" nut driver or socket
wrench reinstall side cover to heater.
Tightenscrewsuntil snug.Do not over
torque!
Unacceptable Acceptable
IGNITION CONTROL
ASSEMBLY

14
105843
PORTABLE FORCED AIR HEATERS
D20N, D30N AND D44N MODELS
2
4
5
6
7
8
9
10
11
12
13
16
9-2
9-1
9-3
9-4
9-5
17
18
19
20
21
22
23
24
26
27
28
29
30
34
35
32 33
9-6
15 14
31
3
1
36
40
38
37
39
25
ILLUSTRATED
PARTS
BREAKDOWN
D20N MODEL
Motor and Pump Assembly
12-11
12-18
12-1712-16
12-1512-14 12-13
12-12
12-10
12-1
12-3 12-4 12-5
12-6
12-7
12-8
12-9
12-2
12-19

15
105843
OWNER’S MANUAL
PARTS LIST
D20N MODEL
This list contains replaceable parts used in your heater. When ordering parts, be sure to
provide the correct model and serial numbers (from the model plate), then the part number
and description of the desired part.
KEY PART
NO. NUMBER DESCRIPTION QTY.
1 105793-01 ON/OFF Switch 1
2 098511-264 Upper Shell 1
3 079919-01 Switch Cover 1
4 102432-01 Screw/Lockwasher, 1/2" 6
5 098512-64 Combustion Chamber 1
6 M10908-2 Screw, #6-32 x 3/8" 2
7 103154-03 Photocell Bracket 1
8 M16656-24 Photocell Assembly 1
9 *** Burner Strap Assembly 1
9-1 100735-25 Nozzle Assembly 1
9-2 102548-05 Ignitor Kit 1
9-3 104056-01 Nozzle Adapter 1
9-4 102336-01 Nozzle Adapter Bracket 1
9-5 M10908-75 Screw, #6-32 x 7/8" 1
9-6 103347-01 Belleville Washer 1
10 102431-01 Screw/Lockwasher, 1/2" 2
11 103684-01 Fan 1
12 *** Motor and Pump Assembly 1
12-1 102001-23 Motor (230V/50 Hz) 1
12-2 079975-02 Pump Body 1
12-3 M22009 Insert 1
12-4 M22456-1 Rotor 1
12-5 M29608 Pump End Cover 1
12-6 M29632 Lint Filter 1
12-7 M29633 Intake Filter 1
12-8 M29609 Filter End Cover 1
12-9 M12461-31 Screw, #10-32 x 1" 3
12-10 M27694 Adjusting Screw 1
12-11 M10993-1 Pressure Relief Spring 1
12-12 M22997 Plug 1
12-13 M8940 Steel Ball, 1/4" Diameter 1
12-14 M29612-01 Output Filter 1
12-15 M12461-31 Screw #10-32 x 1" 6
12-16 103676-01 Nylon Elbow, 90° 1
12-17 M8643 Blade 4
12-18 FHPF3-5C Screw, #10-32 x 5/8" 2
KEY PART
NO. NUMBER DESCRIPTION QTY.
*** Not available as an assembly; order parts separately
12-19 105780-01 Plastic Cap 1
13 M51105-01 Fan Guard 1
14 079673-07 Power Cord 1
15 M50400 Strain Relief Bushing 1
16 NTC-4C Hex Lock Nut, 1/4-20 2
17 102431-01 Screw/Lockwasher, 1/2" 4
18 M50631 Rubber Bumper 2
19 097461-03AA Side Cover 1
20 101205-01 Motor Bracket 1
21 M30865-02 Bushing 1
22 M11271-8 Clip Nut 6
23 M50104-02 Bushing 1
24 102431-01 Screw/Lockwasher, 1/2" 6
25 RF3-5B Screw, #10-32 x 5/8" 1
26 098511-235 Lower Shell 1
27 M50814-06 Rubber Airline 1
28 M29652-05 Fuel Line 1
29 M50876-05 Fuel Filter with bushing 1
30 M10990-3 Rubber Bushing 1
31 102861-01 Nylon Locknut 1
32 102349-01 PCB Support 5
33 104068-04 Ignition Control Assembly 1
34 097702-01 Fuel Cap (Includes Gasket) 1
35 098513-102 Fuel Tank 1
36 079010-40 Wire Assembly (White) 1
37 NPF-3B Nut, #10-32 3
38 097785-01 Vinyl Foam Gasket 1
39 WLE-3 Lockwasher, #10 1
40 079010-39 Wire Assembly (Brown) 1
PARTS AVAILABLE - NOT SHOWN
HA2210 Filler Neck Screen 1
103814-01 Wire Tie 1
103238-01 Tradename Decal 2
105852-01 Decal Package 1

16
105843
PORTABLE FORCED AIR HEATERS
D20N, D30N AND D44N MODELS
1
2
3
23 19
910
16
11
12
15
25
27
24
28
20
22
21
30
31
17
14
14
35
36 32
26
13
18
5
46
7
8
7-2
7-1
7-5
7-4
7-3
7-6
43
4241
33 34
37
40
39
44
38
29
ILLUSTRATED
PARTS
BREAKDOWN
D30N MODEL
Motor and Pump Assembly
10-1
10-2
10-3
10-4 10-5
10-6
10-7 10-8
10-9 10-10
10-11
10-12
10-13 10-14
10-15
10-16
10-17
10-13

17
105843
OWNER’S MANUAL
KEY PART
NO. NUMBER DESCRIPTION QTY.
1 098511-138 Upper Shell 1
2 102432-01 Screw/Lockwasher, 1/2" 8
3 098512-65 Combustion Chamber 1
4 103971-01 Photocell Bracket 1
5 M10908-2 Screw, #6-32 x 3/8" 2
6 M16656-24 Photocell Assembly 1
7 *** Burner Strap Assembly 1
7-1 100735-23 Nozzle Assembly 1
7-2 102548-05 Ignitor Kit 1
7-3 M10908-75 Screw, #6-32 x 7/8" 1
7-4 102336-01 Nozzle Adapter Bracket 1
7-5 104054-01 Nozzle Adapter 1
7-6 103347-01 Belleville Washer 1
8 102431-01 Screw/Lockwasher, 1/2" 2
9 102042-01 Fan 1
10 *** Motor and Pump Assembly 1
10-1 102001-24 Motor 1
10-2 079975-02 Pump Body 1
10-3 FHPF3-5C Screw, #10-32 x 5/8" 2
10-4 M22009 Rotor Insert 1
10-5 M22456-1 Pump Rotor 1
10-6 M50545 Pump End Cover 1
10-7 M12179 Intake Filter 1
10-8 M16545 Filter End Cover 1
10-9 M8940 Steel Ball, 1/4" Diameter 1
10-10 M10993-1 Relief Spring 1
10-11 M27694 Adjusting Screw 1
10-12 M22997 Plug 1
10-13 M12461-31 Screw, #10-32 x 1" 10
10-14 M12244-1 Output Filter 1
10-15 M11637 Lint Filter 1
10-16 M50820-02 Barb Fitting 1
10-17 M8643 Blade 4
11 M50631 Rubber Bumper 2
12 101206-01 Motor Mounting Bracket 1
13 101695-01 Button Plug 1
14 104068-04 Ignition Control Assembly 1
PARTS LIST
D30N MODEL
This list contains replaceable parts used in your heater. When ordering parts, be sure to provide the
correct model and serial numbers (from the model plate), then the part number and description of the
desired part.
*** Not available as an assembly; order parts separately
KEY PART
NO. NUMBER DESCRIPTION QTY.
15 NTC-4C Hex Lock Nut, 1/4-20 2
16 M51114-01 Fan Guard 1
17 M27417 Drain Plug (Includes “o”Ring) 1
18 099213-01 Button Plug 1
19 M51345-06 Fuel Line 1
20 099743-01 Fuel Filter 1
21 M51151-01 Fuel Line Tube 1
22 M10990-3 Rubber Bushing 1
23 M50814-03 Airline 1
24 098511-236 Lower Shell 1
25 M50104-03 Bushing 2
26 M50104-01 Bushing 1
27 102431-01 Screw/Lockwasher, 1/2" 6
28 M11271-8 Clip Nut 8
29 RF3-5B Screw, #10-32 x 5/8" 1
30 098513-91 Fuel Tank 1
31 097702-01 Fuel Cap (Includes Gasket) 1
32 102349-01 P.C. Board Support 5
33 M50400 Strain Relief Bushing 1
34 079673-07 Power Cord 1
35 M51077-09AA Side Cover 1
36 102431-01 Screw/Lockwasher, 1/2" 4
37 102861-01 Nylon Locknut 1
38 079010-39 Wire Assembly (Brown) 1
39 105793-01 ON/OFF Switch 1
40 079919-01 Switch Cover 1
41 WLE-3 Lockwasher, #10 1
42 NPF-3B Nut, #10-32 3
43 097468-01 Edge Liner 1
44 079010-40 Wire Assembly (White) 1
PARTS AVAILABLE - NOT SHOWN
HA2210 Filler Neck Screen 1
103814-01 Wire Tie 1
103238-01 Tradename Decal 2
105852-02 Decal Package 1

18
105843
PORTABLE FORCED AIR HEATERS
D20N, D30N AND D44N MODELS
1
2
3
23 19
910
16
11
12
15
25
27
24
28
20
22
21
30
31
17
14
14
35
36 32
26
13
18
5
46
7
8
7-2
7-1
7-5
7-4
7-3
7-6
43
4241
33 34
37
40
39
44
38
29
ILLUSTRATED
PARTS
BREAKDOWN
D44N MODEL
Motor and Pump Assembly
10-1
10-2
10-3
10-4 10-5
10-6
10-7 10-8
10-9 10-10
10-11
10-12
10-18 10-14
10-15
10-16
10-17
10-13

19
105843
OWNER’S MANUAL
KEY PART
NO. NUMBER DESCRIPTION QTY.
1 098511-138 Upper Shell 1
2 102432-01 Screw/Lockwasher, 1/2" 8
3 098512-66 Combustion Chamber 1
4 103154-05 Photocell Bracket 1
5 M10908-2 Screw, #6-32 x 3/8" 2
6 M16656-24 Photocell Assembly 1
7 *** Burner Strap Assembly 1
7-1 100735-24 Nozzle Assembly 1
7-2 102548-05 Ignitor Kit 1
7-3 M10908-75 Screw, #6-32 x 7/8" 1
7-4 102336-01 Nozzle Adapter Bracket 1
7-5 104054-01 Nozzle Adapter 1
7-6 103347-01 Belleville Washer 1
8 102431-01 Screw/Lockwasher, 1/2" 2
9 102042-01 Fan 1
10 *** Motor and Pump Assembly 1
10-1 102001-24 Motor 1
10-2 079975-03 Pump Body 1
10-3 FHPF3-6C Screw, #10-32 x 3/4" 2
10-4 M22009 Rotor Insert 1
10-5 M22456-2 Pump Rotor 1
10-6 M50545 Pump End Cover 1
10-7 M12179 Intake Filter 1
10-8 M16545 Filter End Cover 1
10-9 M8940 Steel Ball, 1/4" Diameter 1
10-10 M10993-1 Relief Spring 1
10-11 M27694 Adjusting Screw 1
10-12 M22997 Plug 1
10-13 M12461-31 Screw, #10-32 x 1" 4
10-14 M12244-1 Output Filter 1
10-15 M11637 Lint Filter 1
10-16 M50820-02 Barb Fitting 1
10-17 M8643-2 Blade 4
10-18 M12461-32 Screw, #10-32 x 11/8"6
11 M50631 Rubber Bumper 2
12 101206-01 Motor Mounting Bracket 1
13 101695-01 Button Plug 1
PARTS LIST
D44N Model
This list contains replaceable parts used in your heater. When ordering parts, be sure to provide the
correct model and serial numbers (from the model plate), then the part number and description of the
desired part.
*** Not available as an assembly; order parts separately
KEY PART
NO. NUMBER DESCRIPTION QTY.
14 104068-04 Ignition Control Assembly 1
15 NTC-4C Hex Lock Nut, 1/4-20 2
16 M51114-01 Fan Guard 1
17 M27417 Drain Plug (Includes “o”Ring) 1
18 099213-01 Button Plug 1
19 M51345-06 Fuel Line 1
20 099743-01 Fuel Filter 1
21 M51151-02 Fuel Line Tube 1
22 M10990-3 Rubber Bushing 1
23 M50814-03 Airline 1
24 098511-236 Lower Shell 1
25 M50104-03 Bushing 2
26 M50104-01 Bushing 1
27 102431-01 Screw/Lockwasher, 1/2" 6
28 M11271-8 Clip Nut 8
29 RF3-5B Screw, #10-32 x 5/8" 1
30 098513-92 Fuel Tank 1
31 097702-01 Fuel Cap (Includes Gasket) 1
32 102349-01 P.C. Board Support 5
33 M50400 Strain Relief Bushing 1
34 079673-07 Power Cord 1
35 M51077-09AA Side Cover 1
36 102431-01 Screw/Lockwasher, 1/2" 4
37 102861-01 Nylon Locknut 1
38 079010-39 Wire Assembly (Brown) 1
39 105793-01 ON/OFF Switch 1
40 079919-01 Switch Cover 1
41 WLE-3 Lockwasher, #10 1
42 NPF-3B Nut, #10-32 3
43 097468-01 Edge Liner 1
44 079010-40 Wire Assembly (White) 1
PARTS AVAILABLE - NOT SHOWN
HA2210 Filler Neck Screen 1
103814-01 Wire Tie 1
103238-02 Tradename Decal 2
105852-03 Decal Package 1

20
105843
PORTABLE FORCED AIR HEATERS
D20N, D30N AND D44N MODELS
WHEELS AND HANDLES
KEY PART PART D20N D30N D44N
NO. NUMBER DESCRIPTION QTY. QTY. QTY.
1 HA2203 Handles —2—
HA2204 Handles —— 2
097198-02 Handles 1 ——
2 M12345-33 Screw, #10-24 x 1 3/4"48 8
3 M12342-3 Wheel Support Frame —1—
M12831-3 Wheel Support Frame —— 1
097197-02 Wheel Support Frame 1 ——
4 NTC-3C Hex Nut, #10-24 4 8 8
5 107426-01 Wheel (Qty 2) 1 1 1
6 M28526 Cap Nut 2 2 2
7 M51015-01 Axle —1—
M16801-2 Axle —— 1
M51015-04 Axle 1 ——
8 078978-02 Sleeve Cap 2 ——
1
2
3
5
6
4
7
3
1
8
4
2
5
6
7
D30N and
D44N
Models
D20N Model