Desa BC115CT User manual

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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.
CANADIAN PORTABLE FORCED AIR HEATERS
OWNER’S MANUAL
MODELS: BC40, RC40, BC55T, RC55T, BC70T, RC70T, BC115CT,
RC115CT, BC165CT AND RC165CT
TABLE OF CONTENTS
Safety Information ............................................... 2
Unpacking ........................................................... 2
Product Identification ........................................... 3
Assembly ............................................................. 4
Theory of Operation ............................................ 5
Fuels .................................................................... 5
Ventilation ........................................................... 6
Operation ............................................................ 6
Storing, Transporting, or Shipping ....................... 7
Preventative Maintenance Schedule ................... 7
Troubleshooting ................................................... 8
Service Procedures ............................................. 9
Wiring Diagrams ............................................... 15
Illustrated Parts Breakdown and Parts List ....... 16
Specifications .................................................... 24
Accessories ....................................................... 25
Warranty and Repair Service ............................ 28

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2
SAFETY INFORMATION
IMPORTANT: Read this owner’s
manual carefully and completely
before trying to assemble, op-
erate, 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!
Early signs of carbon monoxide poisoning re-
semble the flu, 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 (such as pregnant
women, persons with heart or lung disease, persons
with anemia, those under the influence of alcohol,
and those at high altitudes) are more affected by
carbon monoxide than others.
1. Use only kerosene, #1/#2 diesel/fuel oil, JET A
or JP-8 fuels to avoid risk of fire or explosion.
Never use gasoline, naphtha, paint thinners,
alcohol, or other highly flammable fuels.
2. Use only with the electrical voltage and fre-
quency specified on model plate.
3. Heater must be grounded. Use only a properly
grounded three-wire extension cord. Plug into
grounded outlet only.
4. Use only in areas free of flammable vapors or
high dust content.
5. Minimum clearance from any combustible
materials: 8 feet (244 cm) from hot air outlet;
6 feet (183 cm) from top; and 2 feet (61 cm)
from sides and inlet.
6. Locate heater on a stable and level surface
while hot or operating or a fire may occur.
7. Use only in well ventilated areas. Provide venti-
lation of at least three square feet (2,800 square
cm) for each 100,000 Btu/Hr of rating.
8. Keep children and animals away from heater
at all times.
9. Never start heater when combustion chamber
is hot or if fuel has accumulated in combus-
tion chamber.
10. When used with a thermostat, heater may start
at anytime.
11. When heater is moved or stored, it must be in
a level position or fuel spillage may occur.
12. Use heater only in accordance with local
ordinances and codes.
13. Never use gasoline, crankcase drainings,
naphtha, paint thinners, alcohol, or other
highly flammable fuels.
14. Never use heater where gasoline, paint thin-
ner, or other highly flammable vapors are
present.
15. Never use heater in living or sleeping areas.
16. Never leave a heater plugged in without adult
supervision if children or animals are likely to
be present.
17. Never move, handle, refuel, or service a hot,
operating, or plugged-in heater.
18. Never block air inlet at motor end (rear) of
heater.
19. Never attach duct work to front of heater.
20. Never attach heater to external fuel tank.
UNPACKING
1. Remove all protective packaging that has been
applied to heater for shipment
2. Remove heater from carton.
3. Check heater for any shipping damage. If dam-
age is found, promptly inform dealer where
heater was purchased.

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PRODUCT IDENTIFICATION
Figure 1 - 40 Model
Figure 2 - 55T/70T Models
Handle
Fuel Cap
Lower
Shell
Power Cord
Fuel Tank
Hot Air
Outlet
Air Filter End
Cover
Fan Guard
Upper Shell
Side Cover
Ignition Control Assembly
(assembly on inside of side cover)
Thermostat
Knob
Nose Cone Guard
Side Cover
Fuel Tank
Lower
Shell
Hot Air
Outlet
Nose Cone Guard
Handle
Upper Shell
Power Cord
Fuel Cap
Air Filter
End Cover
Fan Guard
Ignition Control Assembly
(assembly on inside of side cover)
Figure 3 - 115T/165T Models
Lower Shell
Hot Air
Outlet Fan Guard
Fuel Tank
Side Cover
Fuel Cap
Upper Shell
Power Cord
Ignition Control Assembly
(assembly on inside of side cover)
Thermostat Knob

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4
ASSEMBLY
(FOR 40, 55T, AND 70T MODELS ONLY)
These models are furnished with a nose cone
guard. Nose cone guard and mounting screws are
found in the shipping carton.
Tools Needed
• 5/16" Nut Driver or Wrench
1. Place nose cone guard on top of upper shell
flange. Make sure nose cone guard is on hot
air outlet end of heater.
2. Insert screws through nose cone guard and
upper shell flange.
3. Tighten screws firmly.
Figure 4 - Nose Cone Guard Assembly,
40/55T/70T Models Only
Nose Cone
Guard
Screw
Hot Air
Outlet
Upper Shell
Flange
(FOR 115T AND 165T MODELS ONLY)
These models are furnished with wheels and a front
handle. Some models are furnished with a rear
handle also. Wheels, handle(s), and the mounting
hardware is found in the shipping carton.
Tools Needed
• Medium Phillips Screwdriver
• 3/8" Open or Adjustable Wrench
• Hammer
1. Slide axle through wheel support frame. Install
wheels on axle.
IMPORTANT: Place extended hub of wheel
toward wheel support frame.
2. Place cap nuts on axle ends. Gently tap with
hammer to secure.
3. Place heater on wheel support frame assem-
bly. Make sure air inlet end of heater is over
wheels.
4. Place front 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. Tighten all nuts firmly.
Figure 5 - Wheel and Handle Assembly,
115T/165T Models Only
Front
Handle
Hot Air
Outlet
Fuel Tank
Flange
Wheel
Support
Frame
Wheel
Cap Nut Axle
Nut
Extended Hub
Air Inlet
Screw
Rear Handle
(If Equipped)

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THEORY OF OPERATION
The Fuel System: The air pump forces air through
the air line. The 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 com-
bustion chamber.
The Air System: The motor turns the fan. The
fan pushes air into and around the combustion
Figure 6 - Cross Section Operational View
Clean
Heated
Air Out
Fuel
Filter
Air
Output
Filter
Air Pump
Air Intake
Filter
Cool
Air In
Fan
Combustion Chamber
Ignitor Motor
Air For Fuel
System Air For Combustion
And Heating Fuel
Nozzle
Fuel Tank
Ignition Control
Assembly
Air Line
To Burner
chamber. This air is heated and provides a stream
of clean, hot air.
The ignition control assembly provides power to
the ignitor. This ignites the fuel/air mixture in the
combustion chamber.
The Flame-Out Control System: This system causes
the heater to shut down if the flame goes out.
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
or JP-8 fuels. Heavier fuels such as No. 2 fuel
oil or No. 2 diesel fuel may also be used but will
result in:
• noticeable odor
• additional fuel filter maintenance
• the need for nontoxic, anti-icer additives in very
cold weather
Do not use fuels heavier than No. 2 grade or
heavy oils such as oil drained from crankcases.
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.

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6
VENTILATION
WARNING: Provide a fresh air
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 165 model heater requires one of
the following:
• a two-car garage door (16 ft. [4.88 m] wide
opening) raised four inches (10.16 cm)
• a single-car garage door (9 ft. [2.74 m] wide
opening) raised seven inches (17.78 cm)
• two, thirty-inch (76.20 cm) windows raised
twelve inches (30.48 cm)
OPERATION
IMPORTANT: Review and under-
stand the warnings in the Safety
Information section, page 2.
They are needed to safely oper-
ate this heater. Follow all local
ordinances and codes when
using this heater.
TO START HEATER
1. Follow all ventilation and safety informa-
tion.
2. Fill fuel tank with kerosene, #1/#2 diesel/fuel
oil, JET A or JP-8 fuels.
3. Attach fuel cap.
4. For thermostat models 55T, 70T, 115T, and
165T, turn thermostat knob clockwise to the
high position.
5. Plug heaterʼs power cord into approved,
grounded, three-wire extension cord. Extension
cord must be at least six feet (1.8 meters) long.
Extension Cord Size Requirement
6 to 10 feet (1.8 to 3 meters) long, use 18 AWG
(0.75 mm2) rated cord
11 to 100 feet (3.3 to 30.5 meters) long, use
16 AWG (1.0 mm2) rated cord
101 to 200 feet (30.8 to 61 meters) long, use
14 AWG (1.5 mm2) rated cord
6. Plug extension cord into standard 120 volt/60
hertz, 3-prong grounded outlet. Note: Ignitor will
preheat for five seconds, then heater will start.
7. For thermostat models 55T, 70T, 115T, and
165T, adjust thermostat knob to the desired
setting. Note: A cold heater may affect
the thermostat setting. This thermostat is a
general-heating control. It is not intended for
precise temperature control. Adjust thermostat
until heater cycles at the desired setting.
TO STOP HEATER
Unplug extension cord from outlet.
TO RESTART HEATER
1. Unplug extension cord from outlet and wait
10 seconds. (Wait two minutes if heater has
been running.)
2. Repeat steps under To Start Heater.

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Item How Often How To
Fuel tank Flush every 150-200 hours See Storing, Transporting, or
of operation or as needed Shipping
Air output and lint filters Replace every 500 hours of See Air Output, Air Intake,
operation or once a year and Lint Filters, page 10
Air intake filter Wash and dry with soap and See Air Output, Air Intake,
water every 500 hours of and Lint Filters, page 10
operation or replace as needed
Fuel filter Clean twice a heating season See Fuel Filter, page 11
or replace as needed
Ignitor None required
Fan blades Clean every season or See Fan, page 9
as needed
Motor Not required/permanently
lubricated
STORING, TRANSPORTING,
OR SHIPPING
Note: If shipping, transport companies require
fuel tanks to be empty.
1. Drain fuel tank.
Note: Some models have drain plug on un-
derside 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 during future use.
4. Replace fuel cap or drain plug. Properly dis-
pose of old and dirty 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. Using
old fuel could damage heater.
PREVENTATIVE MAINTENANCE SCHEDULE
WARNING: To avoid risk of burn and electrical shock, never at-
tempt to service heater while it is plugged in, operating, or hot.

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8
TROUBLESHOOTING
WARNING: Never service heater while it is plugged in, operating,
or hot. Severe burns and electrical shock can occur.
REMEDY
1. Check circuit breaker in elec-
trical panel
2. Turn thermostat knob to a
higher setting
3. Check all electrical connec-
tions. See Wiring Diagrams,
page 15
4. If fan does not turn freely, see
Pump Rotor, page 14
5. Replace ignition control as-
sembly
6. Replace motor
1. Fill tank with kerosene
2. See Pump Pressure Adjust-
ment, page 10
3. See Fuel Filter, page 11
4. See Nozzle Assembly, page 12
5. Drain and flush fuel tank with
clean kerosene. See Storing,
Transporting, or Shipping,
page 7
6. Check electrical connections.
See Wiring Diagrams , page 15
7. Replace ignitor, see page 11
8. Replace ignition control as-
sembly
1. See Pump Pressure Adjust-
ment, page 10
2. See Air Output, Air Intake, and
Lint Filters, page 10
3. See Fuel Filter, page 11
4. See Nozzle Assembly, page 12
5. Make sure photocell boot is
properly seated in bracket
6. Clean photocell lens
7. Check electrical connections.
See Wiring Diagrams, page 15
8. Replace photocell
9. Replace ignition control as-
sembly
POSSIBLE CAUSE
1. No power to heater
2. Thermostat setting is too low
3. Bad electrical connection be-
tween motor and ignition con-
trol assembly or ignition control
assembly and power cord
4. Binding pump rotor
5. Defective ignition control as-
sembly
6. Defective motor
1. No fuel in tank
2. Pump pressure incorrect
3. Dirty fuel filter
4. Obstruction in nozzle
5. Water in fuel tank
6. Bad electrical connection
between ignitor and ignition
control assembly
7. Defective ignitor
8. Defective ignition control as-
sembly
1. Pump pressure incorrect
2. Dirty air intake, air output,
and/or lint filter
3. Dirty fuel filter
4. Obstruction in nozzle
5. Photocell assembly not properly
installed (not seeing the flame)
6. Dirty photocell lens
7. Bad electrical connection be-
tween photocell and ignition
control assembly
8. Defective photocell
9. Defective ignition control as-
sembly
FAULT CONDITION
Motor does not start five seconds
after heater is plugged in
Motor starts and runs but heater
does not ignite
Heater ignites but ignition control
assembly shuts heater off after a
short period of time
WARNING: High voltage!
WARNING: High voltage!
WARNING: High voltage!

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SERVICE PROCEDURES
WARNING: To avoid risk of
burn and electrical shock, never
attempt to service heater while it
is plugged in, operating, or hot.
UPPER SHELL REMOVAL
1. Remove screws along each side of heater using
5/16" nut-driver. These screws attach upper
and lower shells together. See Figure 7 or 8.
2. Lift upper shell off.
3. Remove fan guard.
Screw
Upper Shell
Fan Guard
Figure 7 - Upper Shell Removal
(40/55T/70T Models Only)
Screw Upper Shell
Fan Guard
Figure 8 - Upper Shell Removal
(115T/165T Models Only)
Figure 9 - Fan, Motor Shaft, and
Setscrew Location
Flush
Fan
Setscrew
Motor Shaft
Motor
Figure 10 - Fan Cross Section
Setscrew
Motor Shaft
Fan
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 (see Figure 9).
1. Remove upper shell (see Figure 7 or 8).
2. Use 1/8" allen wrench to loosen setscrew
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 10).
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.

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10
Air Output
Filter
Lint Filter
Figure 11 - Air Output, Air Intake, and
Lint Filters, 40/55T/70T Models
Figure 12 - Air Output, Air Intake, and
Lint Filters, 115T/165T Models
Filter End
Cover Fan
Guard
Air Output Filter
Lint Filter
Air Intake
Filter Filter End
Cover
Fan
Guard
Air Intake
Filter
AIR OUTPUT, AIR INTAKE AND LINT
FILTERS
1.
Remove upper shell (see Figure 7 or 8, page 9).
2. Remove filter end cover screws using 5/16"
nut-driver. See Figure 11 or 12.
3. Remove filter end cover.
4. Replace air output and lint filters.
5. Wash or replace air intake filter (see Preventa-
tive Maintenance Schedule, page 7).
6. Replace filter end cover.
7. Replace fan guard and upper shell.
IMPORTANT: Do not oil filters.
SERVICE PROCEDURES
Continued
Relief Valve
Pressure
Gauge
Plug
Figure 13 - Pressure Gauge Plug
Removal (40/55T/70T Models Shown)
Pump
Model Pressure
40 3.0 PSI
55T 3.4 PSI
70 T 4.7 PSI
115T 5.1 PSI
165T 5.6 PSI
Pressure
Gauge
Figure 14 - Adjusting Pump Pressure
(40/55T/70T Models Shown)
PUMP PRESSURE ADJUSTMENT
1. Remove pressure gauge plug from filter end
cover (see Figure 13).
2. Install accessory pressure gauge (part number
HA1180).
3. Start heater (see Operation, page 6). 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 correct
pressure for each model (see Figure 14).
5. Remove pressure gauge. Replace pressure
gauge plug in filter end cover.