Desa 100,000 BTU/Hr Models User manual

IMPORTANT: Read and understand this manual before
assembling, starting or servicing heater. Improper use
of heater can cause serious injury. Keep this manual for
future reference.
HEATER SIZES:
100,000, 150,000 AND 200,000 BTU/HR
KEROSENE/DIESEL HEATER WITH BUILT-IN THERMOSTAT
PORTABLE FORCED AIR HEATERS
OWNER’S MANUAL
Save this manual for future reference.
For more information, visit www.desatech.com
1
1
5
3
9
0
1
Heater is suitable
for outdoor use.
Never use heater
in living or
sleeping areas.
Wire Guard
for Canadian
models only.
TABLE OF CONTENTS
Safety .................................................................. 2
Unpacking............................................................ 3
Product Identication........................................... 3
Specications ...................................................... 4
Assembly............................................................. 5
Fuels.................................................................... 8
Ventilation............................................................ 9
Theory of Operation............................................. 9
Operation........................................................... 10
Operation with Portable Generator.....................11
Storing, Transporting or Shipping...................... 12
Preventative Maintenance Schedule................. 12
Troubleshooting................................................. 13
Service Procedures ........................................... 15
Wiring Diagram.................................................. 20
Technical Service............................................... 21
Accessories ....................................................... 21
Parts .................................................................. 22
Replacement Parts............................................ 27
Parts Central...................................................... 27
Warranty ............................................................ 28

www.desatech.com 118419-01E2
SAFETY
d) During fueling, all fuel lines and fuel-
line connections shall be inspected for
leaks.Any leaks shall be repaired prior
to returning the heater to service.
e) At no time shall more than one day's
supply of heater fuel be stored inside
a building in the vicinity of the heater.
Bulk fuel storage shall be outside the
structure.
f) All fuel storage shall be located a
minimum of 762 cm (25 feet) from
heaters, torches, welding equipment
and similar sources of ignition (excep-
tion: fuel reservoir integral with heater
unit or any authorized auxiliary tank
connected to heater unit).
g) Whenever possible, fuel storage
shall be conned to areas where oor
penetrations do not permit fuel to drip
onto or be ignited by a re at lower
elevation.
h) Fuel storage shall be in accordance
with the authority having jurisdiction.
3. Use only the electrical voltage and fre-
quency specied on model plate.
4. Heater is suitable for outdoor use.
5. Heater must be grounded. Use only a
properly grounded three-wire extension
cord. Plug into grounded outlet only.
6. Use only in areas free of ammable va-
pors or high dust content.
7. Minimum clearance from any combust ble
materials: 8 feet (244 cm) from hot air
outlet, 6 feet (183 cm) from top, and 4 feet
(120 cm) from sides and inlet.
8. Locate heater on a stable and level sur-
face while hot or operating or a re may
occur.
9. Heater is acceptable for use on ooring
such as wood (a combust ble material).
10. 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 30 kw (100,000 Btu/Hr)
of rating.
11. Keep children and animals away from
heater at all times.
12. Never start heater when combustion
chamber is hot or if fuel has accumulated
in combustion chamber.
13. This heater is equipped with a thermostat.
Heater may start at anytime.
WARNING: This product
contains and/or generates
chemicals known to the State
of California to cause cancer or
birth defects or other reproduc-
tive harm.
IMPORTANT: Read this owner’s
manualcarefullyandcompletely
before trying to assemble,
operate or service this heater.
Improper use of this heater can
cause serious injury or death
from burns, fire, explosion,
electrical shock and carbon
monoxide poisoning.
DANGER: Carbon monoxide
poisoning may lead to death!
Carbon Monoxide Poisoning: Early signs
of carbon monoxide poisoning resemble the
u, with headaches, dizziness and/or nausea.
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.
These include pregnant women, persons
with heart or lung disease or anemia, those
under the inuence of alcohol and those at
high altitudes.
Make certain you read and understand all
warnings. Keep this manual for reference. It
is your guide to safe and proper operation of
this heater.
1. Use only kerosene, #1/#2 diesel/fuel oil,
JET A or JP-8 fuels to avoid risk of re or
explosion. Never use gasoline, oil from
crank cases, naphtha, paint thinners,
alcohol or other highly ammable fuels.
2. Fueling
a) Personnel involved with fueling shall
be qualied and thoroughly familiar
with the manufacturer's instructions
and applicable regulations regarding
the safe fueling of heating units.
b) Only the type of fuel specied on the
heater's data plate shall be used.
c) All ame shall be extinguished and the
heater allowed to cool, prior to fueling.

www.desatech.com
118419-01E 3
14. Never leave a heater plugged in without
adult supervision if children or animals are
likely to be present.
15. Use caution when moving or storing
heater when fuel tank contains fuel. Fuel
spillage can occur.
16. Use heater only in accordance with lo-
cal ordinances and codes. Canadian
residents should refer to CSA standard
B139, Installation Code for Oil Burning
Equipment for recommended installation
practice.
17. Never use gasoline, crankcase drainings,
naphtha, paint thinners, alcohol or other
highly ammable fuels.
18. Never use heater where gasoline, paint
thinner or other highly ammable vapors
are present.
19. Never use heater in living or sleeping
areas.
20. Never move, handle, refuel or service a
hot, operating or plugged-in heater.
SAFETY
Continued
21. Never attach duct work to front or rear of
heater.
22. Heaters used in the vicinity of tarpaulins,
canvas or similar enclosure materials shall
be located a safe distance from such ma-
terials. The recommended minimum safe
distance is 304.8 cm (10 feet). It is further
recommended that these enclosure ma-
terials be of a re retardant nature. These
enclosure materials shall be securely fas-
tened to prevent them from igniting or from
upsetting the heater due to wind action.
23. Unplug heater when not in use.
24. Never block air inlet (rear) or air outlet
(front) of heater.
25. Warning to New York City Residents
For Use Only At Construction Sites in
accordance with applicable NYC codes
under NYCFD certificate of approval
#4803, #4899 and #4909.
26. Never use external fuel sources or tanks
that are not specically designed for use
with this heater.
Hot Air
Outlet
Fuel Cap
Fuel Tank
ON/OFF Switch
Lower Shroud
Front
Handle
Figure 1 - 100, 150 and 200 Models
UNPACKING
Upper Shroud
Cold Air Inlet
Thermostat
Touch Pad
Fuel Gauge
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 call DESA Heating,
LLC at 1-866-672-6040 for replacement
parts before returning to dealer.
PRODUCT IDENTIFICATION
Wire Guard
(Canadian
models only,
see page 24)
Extension
Cord Wrap
Temperature
Display
Rubber Foot
Handle
Grip
Handle Crossbar

www.desatech.com 118419-01E4
SPECIFICATIONS
100 Models
• Output Rating: 100,000 Btu/Hr
• Fuel: Use only kerosene, #1/#2 diesel*/fuel oil, JET A or JP-8 fuels
• Fuel Tank Capacity: 13.5 gal (51.1 liters)
• Fuel Consumption per Hr: 0.75 gal (2.84 liters)
• Pump Pressure (psi): 5.9
• Electric Requirements: 120 V/60 HZ
• Amperage (Normal Run): 4.2
• Typical Motor Speed (RPM): 3315
• Motor Horsepower: 1/5
• Shipping Weight (Approx.): 71 lb (32.2 kg)
• Heater Weight without Fuel (Approx.): 60 lb (27.2 kg)
150 Models
• Output Rating: 150,000 Btu/Hr
• Fuel: Use only kerosene, #1/#2 diesel*/fuel oil, JET A or JP-8 fuels
• Fuel Tank Capacity: 13.5 gal (51.1 liters)
• Fuel Consumption per Hr: 1.13 gal (4.28 liters)
• Pump Pressure (psi): 6.4
• Electric Requirements: 120 V/60 HZ
• Amperage (Normal Run): 4.2
• Typical Motor Speed (RPM): 3300
• Motor Horsepower: 1/4
• Shipping Weight (Approx.): 71 lb (32.2 kg)
• Heater Weight without Fuel (Approx.): 60.5 b (27.4 kg)
200 Models
• Output Rating: 200,000 Btu/Hr
• Fuel: Use only kerosene, #1/#2 diesel*/fuel oil, JET A or JP-8 fuels
• Fuel Tank Capacity: 13.5 gal (51.1 liters)
• Fuel Consumption per Hr: 1.45 gal (5.49 liters)
• Pump Pressure (psi): 7.1
• Electric Requirements: 120 V/60 HZ
• Amperage (Normal Run): 4.2
• Typical Motor Speed (RPM): 3300
• Motor Horsepower: 1/4
• Shipping Weight (Approx.): 73 lb (33.1 kg)
• Heater Weight without Fuel (Approx.): 62.5 b (28.3 kg)
* Use of #2 diesel/fuel oil will result in noticeable odor and could require additional fuel lter
maintenance. Use in extreme cold temperatures may require nontoxic anti-icer additives.

www.desatech.com
118419-01E 5
ASSEMBLY
Estimated assembly time: 20 minutes
Tools Needed
• 5/16" nut driver or wrench
• 7/16" socket/ratchet or wrenches
• #4 Phillips screw driver
All models are furnished with a wheel, mounting hardware and handles. Parts will be found
in shipping carton.
You should have the following assembly parts:
Wheel (1),Axle (1), Handle Crossbar (1), Rear Cross Support (1), Legs (2), Rubber Feet (2), Rear
Handles (2), Front Handle (1), Handle Grips (2), Extension Cord Wraps (2) (see page 26).
Parts are referenced by designated letter throughout assembly instructions. Hardware packet
provided with heater may contain more parts than needed for heater assembly. Hardware
packet, part number 122094-01, contains the following (quantity used in parenthesis):
D
A
AE
B
B
D
C
C
C
A
B
CD
E
Description Part No.
A 5/16" - 18 x 7/8 PPH (4) 121123-03
B Spacer (2) 113497-02
C 5/16" - 18 x 1 1/2PPH (4) 121123-04
D 1/4" - 20 x 2 3/4Bolt (4) HC4-22C
E 1/4 - 20 Nut (4) NTC-4C

www.desatech.com 118419-01E6
ASSEMBLY
Continued
Figure 2 - Attaching Wire Guard
Wire Guard (Canadian Models)
1. Remove two screws securing front of up-
per shell to lower shell (see Figure 2).
2. Place wire guard on top of upper shell
ange.
3. Insert screws through wire guard and up-
per shell ange. Tighten screws rmly.
Wire
Guard
Upper Shell
Wire Guard Screws
(Canadian models only)
Rear
Cross
Support
Bolt (A)
Figure 3 - Attaching Rear Cross Support
Wheel and Handles
IMPORTANT: Install hardware nger tight only
at this time. After assembly is complete, use
tools to tighten entire assembly
1. Place heater with bottom of tank at on
oor.
2. Attach rear cross support with two bolts
(A), see Figure 3.
3. Push rubber feet onto each leg (left and
right), see Figure 4.
Figure 4 - Rubber Feet and Legs
Figure 5 - Legs Attached to Rear Cross
Support
Bolt (A)
Rear Cross Support
Leg
Axle
Wheel
Figure 6 - Wheel and Axle
Spacer
(B)
4. Assemble each leg (left and right) onto
each side of rear cross support. Loosely
secure each side with bolts (A) (see Fig-
ure 5).
5. Lift front of heater so it is resting on back of
shroud and back of legs (see Figure 8).
6. Insert axle through wheel. Slide one
spacer (B) onto each end of wheel axle.
See Figure 6.

www.desatech.com
118419-01E 7
ASSEMBLY
Continued
7. Assemble wheel axle into front holes of
legs (see Figure 7).
8. Secure front legs to tank with two bolts
(C) (see Figure 8).
9. Tighten bolts from step 4 securing legs to
rear cross support.
10. Set heater down to oor on wheel and rear
legs.
Figure 7 - Installing Wheel and Axle
Wheel
Leg
Figure 8 - Attaching Legs to Tank
Bolt (C)
Figure 9 - Front and Rear Handle
Assembly
Front
Handle
Rear
Handle
Bolt (D)
Figure 10 - Handle and Leg Assembly
Leg
Handle Assembly
Nut (E)
11. Slide rear handle onto each end of front
handle. Insert bolts (D) into holes (2 per
side) (see Figure 9).
12. Lift handle assembly over heater. Align
and guide bolts into holes in leg.
13. Secure assembly with nuts (E) (see
Figure 10).
14. Tighten entire assembly with tools.

www.desatech.com 118419-01E8
FUELS
WARNING: Use only kero-
sene, #1/#2 diesel/fuel oil, JET
A or JP-8 fuels to avoid risk
of fire or explosion. Never
use gasoline, oil drained from
crankcases, naphtha, paint
thinners, alcohol or other highly
flammable fuels.
Use only kerosene, #1/#2 diesel*/fuel oil,
JET A, JP-8 fuels. Heavier fuels such as No.
2 fuel oil, No. 2 diesel fuel may also be used
but will result in:
• noticeable odor
• additional fuel lter maintenance
* Use of #2 diesel/fuel oil in extreme cold
temperatures may require nontoxic anti-icer
additives.
Do not use fuels heavier than No. 2 grade
or heavy oils such as oil drained from crank-
cases. These heavy oils will not ignite properly
and will contaminate the heater.
IMPORTANT: Use a KEROSENE ONLY (blue)
or DIESEL ONLY (yellow) storage container.
Be sure storage container is clean. Foreign
matter such as rust, dirt or water will cause the
ignition control assembly to shut down heater.
Foreign matter may also require heater's fuel
system to be frequently cleaned.
15. Assemble extension cord wrap to each
rear handle (see Figure 11).
16. Push handle grips onto handles (see
Figure 11).
17. Attach handle crossbar with 2 bolts (C)
ASSEMBLY
Continued
Figure 11 - Handle Grip and Cord Cleat
Assembly
Handle
Grip
Extension
Cord Wrap Handle
Crossbar

www.desatech.com
118419-01E 9
VENTILATION
WARNING:Provideafreshair
opening of at least three square
feet (2,800 square cm) for each
100,000 BTU/HR rating. Provide
extra fresh air if more heaters
are being used. The minimum
ventilation requirements must
be followed to avoid risks as-
sociated with carbon monoxide
poisoning. Make certain these
requirements are met prior to
operating heater.
Example: A 200,000 Btu/Hr (58.6 kw) heater
requires one of the following:
• a two-car garage door [16 feet (4.88 meter)
opening] raised 5" (12.7 cm)
• a single-car garage door [9 feet (2.74 me-
ter) opening] raised 8" (20.3 cm)
• two, 30" (76.2 cm) windows raised 15"
(38.1 cm)
THEORY OF OPERATION
The Fuel System: The air pump forces air
through the air line.Air is then pushed through
the nozzle. This air causes fuel to be lifted
from the tank. A fine mist of fuel is sprayed
into the combustion chamber.
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 high voltage ig-
nitor provides power to the spark ignitor. This
ignites the fuel/air mixture in the combustion
chamber.
The Flame-Out Control System: This sys-
tem causes the heater to shut down if the
flame goes out.

www.desatech.com 118419-01E10
OPERATION
IMPORTANT: Reviewandunder-
stand the warnings in the Safety
section,page2.Theyareneeded
to safely operate this heater.
Follow all local ordinances and
codes when using this heater.
TO START HEATER
1. Follow all ventilation and safety information.
2. Locate heater to provide maximum circu-
lation of the heated air. Follow all location
requirements noted in Safety, page 2.
3. Fill fuel tank with fuel. Use only kerosene,
#1/#2 diesel/fuel oil, JET A or JP-8 fuels to
avoid risk of re or explosion. Never use
gasoline, oil drained from crank cases,
naphtha, paint thinners, alcohol or other
ammable fuels.
4. Attach fuel cap.
5. Plug heater’s power cord into approved,
grounded, three-wire extension cord.
Extension cord must be at least six feet
(1.8 m) long.
Extension Cord Size Requirement
6 to 10 feet (1.8 to 3 m) long, use 18AWG
(0.75 mm2) rated cord
11 to 100 feet (3.3 to 30.5 m) long, use 16
AWG (1.0 mm2) rated cord
101 to 200 feet (30.8 to 61 m) long, use
14 AWG (1.5 mm2) rated cord
6. Plug extension cord into standard 120
volt/60 hertz, 3-prong grounded outlet.
7. Push ON/OFF switch to the ON (|) position.
8. Wait 10 seconds for LED to display. Adjust
thermostat by pressing to change set
point higher. Press to change set tem-
perature lower. If heater set temperature is
higher than the surrounding air tempera-
ture, heater should ignite immediately. If
heater thermostat set temperature is lower
than surrounding air temperature, heater
will not ignite.
A cold heater may affect the thermostat
setting. This thermostat is a general-heat-
ing control. It is not intended for precise
temperature control. Adjust thermostat
until heater cycles at the desired setting.
Lighted ON/OFF
Switch Thermostat
Control
Temperature
Display
Figure 13 - Control Cover with
Temperature Display
Temperature
Sensor
WARNING: This heater is
equipped with a thermostat.
Heater may start at any time.
TO STOP HEATER
1. Push ON/OFF switch to the OFF (O)
position.
2. Unplug heater when not in use.
TO RESET HEATER
1. Push ON/OFF switch to the OFF (O)
position and wait 10 seconds. (Wait two
minutes if heater has been running.)
2. Repeat steps under To Start Heater.
Temperature Display
This heater is equipped with a digital tem-
perature display. The temperature being shown
represents the air nearest to control cover.
The temperature of air in surrounding areas
may be much different from temperature be-
ing displayed. Display may show [ ] when
thermostat control or temperature sensor are
disconnected from control or if they are dam-
aged. If this occurs, control will continue to
operate as before, however, unit will not cycle
off during operation. See Figure 13.

www.desatech.com
118419-01E 11
WARNING: Never service
heater while it is plugged in,
operating or hot. Severe burns
and electrical shock can occur.
OPERATION
Continued
Error Codes
This heater will display error codes whenever
there is an abnormal shutdown or problems
with supply voltage. Make sure you have read
all instructions and see Troubleshooting, page
13, before attempting to rectify any problems
with your heater.
Figure 14 - Controls Display
Display Codes
C1 = Low Voltage
C2 = High Voltage
C3 = No Ignition
C4/C5 = Out of Fuel or Fault*
* See fault codes in your owner’s manual.
LED display will show surrounding temperature unless up and down arrow keys are
pressed. After pressing these keys, display shows set point temperature for a second and
then will change back to display surrounding temperature.
This thermostat will store the last set point even if power is removed. Unit will maintain this
set point until a new set point is entered.
Increase and Decrease
Temperature Setting
Ground Lug
Ground Wire (#10 AWG
- Stranded-Copper)
Copper
or Brass
Grounding
Point
Alternator
Figure 15 - Typical Generator Grounding
Method (Generator construction may
vary from that shown)
OPERATION WITH PORTABLE GENERATOR
WARNING: Before operating
heater or any appliance from a
portable generator, verify that
generatorhasbeenproperlycon-
nectedtoearthground.Improper
grounding or failure to ground
generator can result in electro-
cution if a ground fault occurs.
Refertoowner’smanualsupplied
by generator manufacturer for
proper grounding procedures.
Operating voltage range of heater is 108 to
132 Volts (120 Volts +/- 10%). Prior to plug-
ging heater into generator output voltage
should be veried (if generator is equipped
with automatic idle feature, output voltage
should be measured with generator running
at full speed). If voltage does not measure in
this range heater should not be plugged into
generator.
Refer to Operation, page 10, for starting, stop-
ping and resetting heater procedures.

www.desatech.com 118419-01E12
STORING, TRANSPORTING OR SHIPPING
Note: If shipping, transport companies require
fuel tanks to be empty.
1. Remove excess fuel from tank using a si-
phon pump. Drain remaining fuel through
ller neck by tipping heater on its side.
2. 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 lters during future use.
3. Properly dispose of old and dirty fuel.
Check with local automotive service sta-
tions that recycle oil.
4. 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 heat-
ing season. Using old fuel could damage
heater.
PREVENTATIVE MAINTENANCE SCHEDULE
WARNING: Never service heater while it is plugged in, operating
or hot. Severe burns and electrical shock can occur.
How To
See Storing, Transporting,
or Shipping
See Air Output, Air Intake
and Lint Filters, page 16
See Air Output, Air Intake
and Lint Filters, page 16
See Fuel Filter, page 17
See Spark Ignitor, page 17
See Fan, page 15
Item
Fuel tank
Air output and lint filters
Air intake filter
Fuel filter
Spark Ignitor
Fan blades
Motor
How Often
Clean every season or as needed
Replace every 500 hours of operation
or once a year
Washanddrywithsoapandwaterevery
500 hours of operation or as needed
Clean twice a heating season or as
needed
Clean and regap every 500 hours of
operation or replace as needed
Clean every season or as needed
Not required/permanently lubricated

www.desatech.com
118419-01E 13
TROUBLESHOOTING
WARNING: Never service heater while it is plugged in, operating
or hot. Severe burns and electrical shock can occur.
POSSIBLE CAUSE
1. No power to heater
2. Thermostat setting is too
low
3. Bad electrical connection
between motor and control
assembly, or control and
ON/OFF switch, or ON/OFF
switch and power cord
4. Binding pump rotor
5. Defective control assembly
6. Defective motor
7. Defective ON/OFF switch
8. Heater is being supplied with
voltage below 108 volts, 60
Hz. Poor supply circuit, exten-
sion cord too long or gauge of
cord is too small to support
the power requirements for
heater. See extension cord
size requirements on page 8
9. Heater is being supplied
with voltage above 132
volts
1. No fuel in tank
2. Pump pressure incorrect
3. Dirty fuel lter
4. Obstruction in nozzle
5. Water in fuel tank
6. Bad electrical connection
between spark ignitor and
control assembly
7. Defective spark ignitor
8. Defective control assembly
9. Electronic ignitor not
grounded
REMEDY
1. Check circuit breaker in
electrical panel
2. Adjust thermostat to a high-
er setting by pressing or
on touch pad
3. Check all electrical connec-
tions. See Wiring Diagram,
page 20
4. If fan does not turn freely,
see Pump Rotor, page 19
5. Replace control assembly
6. Replace motor
7. Replace ON/OFF switch
8. Conrm supply voltage is
above 108 volts
9. Conrm supply voltage is
below 132 volts
1. Fill tank. See Fuels, page 8
2. See Pump Pressure Adjust-
ment, page 16
3. See Fuel Filter, page 17
4. See Noz zle Assem bly,
page 17
5. Drain and ush fuel tank
with clean kerosene. See
Storing, Transporting or
Shipping, page 12
6. Check electrical connec-
tions. See Wiring Diagram,
page 20
7. Replace spark ignitor, see
page 17
8. Replace control assembly
9. Loose wire connections.
Defective or loose ground
wire. Check electrical con-
nections. See Wiring Dia-
gram, page 20
FAULT CONDITION
Motor does not start after
heater is plugged in and ON/
OFF switch is on (|)
Code C1 appears on control
panel display
C1 = Low Voltage
Code C2 appears on control
panel display
C2 = High Voltage
Motor starts and runs but
heater does not ignite. Code
C3 appears on control panel
display. C3 = No Ignition
WARNING: High voltage!
WARNING: High voltage!

www.desatech.com 118419-01E14
POSSIBLE CAUSE
1. Pump pressure incorrect
2. Dirty air intake, air output,
and/or lint lter
3. Dirty fuel lter
4. Obstruction in nozzle
5. Photocell assembly not
properly installed (not see-
ing the ame)
6. Dirty photocell lens
7. Bad electrical connection
between photocell and con-
trol assembly
8. Defective photocell
9. Defective control assembly
1. Not enough fuel in tank to
maintain combustion
2. Heater inlet or outlet is cov-
ered and unit is not getting
enough air for combustion
REMEDY
1. See Pump Pressure Adjust-
ment, page 16
2. See Air Output, Air Intake,
and Lint Filters, page 16
3. See Fuel Filter, page 17
4. See Nozzle Assembly,
page 17
5. Make sure photocell boot is
properly seated in bracket
6. Clean photocell lens
7. Check electrical connec-
tions. See Wiring Diagram,
page 20
8. Replace photocell
9. Replace control assembly
1. Add fuel and restart unit
2. Remove obstructions or
loose material from heater
inlet or outlet
FAULT CONDITION
Heater ignites but control as-
sembly shuts heater off after
a short period of time
Code C4 or C5 appear on
control panel display
C4/C5 = Out of Fuel or Fault
TROUBLESHOOTING
Continued
WARNING: High voltage!

www.desatech.com
118419-01E 15
SERVICE PROCEDURES
WARNING: To avoid risk of
burn and electrical shock, never
attempt to service heater while it
is plugged in, operating or hot.
SHROUD AND UPPER SHELL
1. Using a #4 Phillips screwdriver, remove 2
bolts securing handle crossbar to handles
(see Figure 16).
Upper Shroud
Figure 16 - Upper Shell Removal (200 Model Shown)
Upper Shell
2. Remove single screw securing upper
shroud using 5/16" nut driver (see Figure
16). Open shroud carefully by pulling up
on both sides.
3. Remove 6 screws along each side of
heater using 5/16" nut driver. These
screws attach upper and lower shells
together (see Figure 16).
4. Lift upper shell off.
Upper Shroud Screw
FAN
1. Remove upper shell (see Shroud and
Upper Shell).
2. Disconnect wires from various connection
points. Remove 2 screws securing blower
to lower shell (see Figure 17). Carefully
lift blower assembly from heater.
3. Remove 4 bolts and nuts securing blower
assembly (see Figure 17).
Motor Inlet
Ring
Screw
Figure 18 - Fan, Motor Shaft, and
Setscrew Location
Blower
Sleeve
Figure 17 - Removing Blower Assembly
Blower Assembly Bolt Nut
Blower
Housing
Nut
Motor
Support
Screw
4. Remove 3 screws securing blower sleeve
to blower housing (see Figure 18). Set
blower sleeve aside.
Handle
Crossbar

www.desatech.com 118419-01E16
AIR OUTPUT, AIR INTAKE AND LINT
FILTERS
1. Remove lter end cover screws using
5/16" nut-driver (see Figure 20).
2. Remove lter end cover.
3. Replace air output and lint lters.
4. Wash or replace air intake lter (see Preven-
tative Maintenance Schedule, page 12).
5. Replace lter end cover.
IMPORTANT: Do not oil lters.
6. Proceed to Pump Pressure Adjustment.
Figure 20 - Air Output, Air Intake, and
Lint Filters
SERVICE PROCEDURES
Continued
Figure 21 - Pressure Gauge Plug Removal
Pressure
Gauge Plug Relief Valve
Air Intake Filter
Lint Filter
Filter End
Cover
Air Output Filter
PUMP PRESSURE ADJUSTMENT
1. Remove pressure gauge plug from lter
end cover (see Figure 21).
2. Install accessory pressure gauge (part
number HA1180, see page 19).
3. Start heater (see Operation, page 10).
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 specica-
tions correct pressure for each model (see
Figure 22, page 17).
5. Remove pressure gauge. Replace pres-
sure gauge plug in lter end cover.
Motor Shaft
Fan
Setscrew
Figure 19 - Fan Side View
Motor
Measure Gap
Between Fan
and Housing
(typical range:
0.26"-0.27")
5. Rotate fan so set screw is visible (see
Figure 19). Measure gap from side of fan
to side of housing. Make note of measure-
ment.
6. Remove 3 nuts securing motor support
to blower housing (see Figure 18). Care-
fully remove motor assembly from blower
housing.
7. Use T20 torx driver to loosen setscrew
which holds fan to motor shaft.
8. Slip fan off motor shaft.
9. Rinse fan under running water. Kerosene
may be required if there are dirt and oil
deposits on fan.
10. Dry fan thoroughly.
11. Replace fan on motor shaft.
12. Replace motor assembly and sleeve.
13. Rotate fan back to point where set screw
is visible.
14. Set gap (measured in step 5) and tighten
fan set screw on at of motor shaft to 80
inch-lbs.
15. Replace blower assembly and reconnect
wires.
16. Replace upper shell and upper shroud.

www.desatech.com
118419-01E 17
Pressure
Gauge
Figure 22 - Adjusting Pump Pressure
Pump
Model Pressure
100 5.9 PSI
150 6.4 PSI
200 7.1 PSI
Figure 23 - Fuel Filter Removal
Fuel Filter
Upper
Fuel
Line
Lower
Fuel
Line
Bushing
Fuel Filter
SERVICE PROCEDURES
Continued
SPARK IGNITOR
1. Open upper shroud and remove upper shell
(see Shroud and Upper Shell, page 15).
2. Disconnect ignitor wire from spark ignitor.
3. Remove spark ignitor screw with a 1/4"
nut driver. Carefully remove spark ignitor
from nozzle adapter bracket.
4. Clean and regap spark ignitor to 0.110".
5. Reassemble spark ignitor, shroud and
upper shell.
Figure 24 - Removing Spark Ignitor
Combustion
Chamber
Ignitor
Nozzle
Adapter
Bracket
NOZZLE ASSEMBLY
(For 100 and 150 Models Only)
1. Open upper shroud and remove upper shell
(see Shroud and Upper Shell, page 15).
2. Disconnect air and fuel lines.
3. Turn nozzle assembly to notch in bracket
and pull toward motor to remove (see
Figure 25).
4. Place plastic hex-body into vise and lightly
tighten.
Figure 25 - Removing Nozzle/Adapter
Assembly (100/150 Models)
Nozzle
Adapter
Bracket
Combustion
Chamber
Nozzle
Adapter
Air and
Fuel
Lines
FUEL FILTER
1. Open upper shroud (see Shroud and Up-
per Shell, page 15).
2. Pull upper fuel line off fuel lter neck (see
Figure 23).
3. Carefully pry bushing, fuel lter, and lower
fuel line out of fuel tank (see Figure 23).
4. Wash fuel lter with clean fuel and replace
in tank.
5. Attach upper fuel line to fuel lter neck.
6. Replace upper shroud.
Barb Fitting Points
Towards Blower
Housing

www.desatech.com 118419-01E18
SERVICE PROCEDURES
Continued
Figure 27 - Removing Nozzle/Adapter
Assembly (200 Model)
Nozzle Face
Nozzle
Nozzle
Sleeve
Nozzle
Adapter
Bracket
Air Line
Fitting
Fuel Line Fitting
Figure 28 - Nozzle and Nozzle Adapter
(200 Model)
Nozzle
Adapter
(For 200 Model Only)
1. Open upper shroud and remove upper shell
(see Shroud and Upper Shell, page 15).
2. Disconnect air and fuel lines.
3. Disconnect spark ignitor wire.
4. Remove two nozzle adapter bracket
screws (see Figure 27).
5. Place hex-shaped aluminum nozzle
adapter into vise (do not overtighten).
6. Carefully remove nozzle from nozzle
adapter using 5/8" socket wrench (see
Figure 28).
Nozzle
Adapter
Bracket
Combustion
Chamber
Nozzle
Adapter
Nozzle
Adapter
Bracket
Screw
Spark Ignitor
Fuel Line
Air Line
7. Blow compressed air through face of
nozzle. This will remove any debris in
nozzle.
8. Inspect nozzle seal for damage.
9. Replace nozzle into nozzle adapter until
nozzle seats. Tighten 80-110 in- bs.
10. Attach nozzle adapter bracket to combus-
tion chamber with two screws removed in
step 4.
11. Reconnect spark ignitor wire, fuel line and
air line.
12. Replace upper shell, upper shroud and
handle crossbar.
Figure 26 - Nozzle and Nozzle Adapter
(100/150 Models)
Nozzle Face
Nozzle
Nozzle Sleeve
Nozzle Adapter
Air Line
Fitting Fuel Line Fitting
5. Carefully remove nozzle from the nozzle
adapter using 5/8" socket wrench (see
Figure 26).
6. Blow compressed air through face of
nozzle. This will free any dirt in nozzle
area.
7. Inspect nozzle sleeve for damage.
8. Replace nozzle into nozzle adapter until
nozzle seats. Tighten 1/3 turn more using
5/8" socket wrench 4.5 to 5.1 N-m (40 to
45 in- bs).
9. Replace nozzle adapter into bracket (see
Figure 25, page 15) and rotate to position
shown in Figure 24, page 15.
10. Attach fuel and airline hoses to nozzle
assembly. See Fuel and Air Line Replace-
ment and Proper Routing, page 19.
11. Replace upper shell and upper shroud.

www.desatech.com
118419-01E 19
Figure 29 - Air Hose to Barb Fitting
Air Hose
Pump
End
Cover
Barb
Fitting
FUEL AND AIR LINE REPLACEMENT
AND PROPER ROUTING
1. Open upper shroud (see Shroud and Up-
per Shell, page 14).
2. Inspect fuel and air line hoses for cracks
and/or holes. If fuel line hose is damaged,
disconnect from nozzle adapter (see Fig-
ure 24, page 17 or Figure 27) and from
fuel lter (see Fuel Filter, page 16). If air
line hose is damaged, disconnect from
nozzle adapter (see Figure 24, page 17 or
Figure 27, page 18) and from barb tting
on pump end cover (see Figure 29).
3. Install new air and/or fuel line. Attach one
end of air line hose to barb tting on pump
end cover (see Figure 29) and the other
end to nozzle adapter (see Figure 24,
page 17 or Figure 27, page 18). Attach
one end of fuel line hose to fuel lter (see
SERVICE PROCEDURES
Continued
Pump
Plate
Insert
Rotor
Blade
Filter
End
Cover
Air Intake
Filter
Air Output
Filter
PUMP ROTOR
(Procedure if Rotor is Binding)
1. Remove filter end cover screws using
5/16" nut driver (see Figure 31).
2. Remove filter end cover and air filters.
3. Remove pump plate screws using 5/16"
nut driver.
4. Remove pump plate.
5. Remove rotor, insert, and blades (see
Figure 31).
6. Check for debris in pump. If debris is
found, blow out with compressed air.
7. Install insert and rotor.
8. Check gap on rotor. Adjust to 0.076/
0.101 mm (0.003"/0.004") if needed (see
Figure 32, page 20).
Note: Rotate rotor one full turn to ensure
the gap is 0.076/0.101 mm (0.003"/0.004")
at tightest position. Adjust if needed.
Figure 31 - Rotor Location
9. Install blades, pump plate, air filters, and
filter end cover.
Note: Be sure to install parts back in
original orientation.
Figure 30 - Routing Air and Fuel Lines
Fuel Line (do not allow fuel
line to droop and trap fuel)
Air Line Under Fuel Line
100 & 150 Models 200 Models
Fuel Line (do not allow fuel
line to droop and trap fuel)
Air Line
Fuel Filter, page 17) and the other end to
nozzle adapter (see Figure 24, page 17
or Figure 27, page 18).
Note: Route hoses as shown in Figure
30. Hoses are not to touch photocell
bracket.
4. Replace upper shell, upper shroud and
handle crossbar..

www.desatech.com 118419-01E20
SERVICE PROCEDURES
Continued
Gap Adjusting Screw
Rotor
Blade
0.003"/0.004"
(0.076-0.101 mm)
Gap Measured
With Feeler
Gauge
Gap Adjusting Screw
Figure 32 - Gap Adjusting Screw
Locations
Sandpaper
Figure 33 - Sanding Rotor
10. Adjust pump pressure (see Pump Pres-
sure Adjustment, page 16).
Note: If rotor is still binding, proceed as
follows.
11. Perform steps 1 through 6.
12. Place fine grade sandpaper (600 grit) on
flat surface. Sand rotor lightly in “figure 8”
motion four times (see Figure 33).
13. Reinstall insert and rotor.
14. Perform steps 8 through 10, page 19.
WIRING DIAGRAM
Photocell
Thermistor Motor
High
Voltage
Ignitor
Spark
Ignitor
Red
C
O
N
T
R
O
L
Blue
Blue Green
White
White
White
Red
White
Black
Black
Black
Black
Black
On/Off
Switch
Thermostat
Touch Pad
Blue Side
of Metal
Conductors
Power Plug
120V/60HZ
Green
Green