Desa Tech TA110 Owner's Manual

PORTABLE FORCED AIR HEATERS

OWNER’S MANUAL

HEATER SIZES:

125,000, 170,000 AND 200,000 BTU/HR

KEROSENE/DIESEL HEATER WITH BUILT-IN THERMOSTAT

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.

TABLE OF CONTENTS

Safety Information ............................................... 2

Unpacking............................................................ 3

Fuels .................................................................... 3

Product Identication ........................................... 3

Theory of Operation............................................. 4

Ventilation ............................................................ 4

Assembly ............................................................. 4

Operation ............................................................. 5

Operation with Portable Generator ...................... 7

Storing, Transporting or Shipping ........................ 7

Preventative Maintenance Schedule ................... 8

Troubleshooting ................................................... 8

Service Procedures ........................................... 10

Specications .................................................... 15

Wiring Diagrams ................................................ 16

Technical Service............................................... 17

Replacement Parts ............................................ 17

Accessories ....................................................... 17

Illustrated Parts Breakdown and Parts List........ 18

Warranty and Repair Service ............................ 28

Fill In For Your Records

Model No. __________________
(Located on side panel)

Serial No. __________________
(Located on fuel tank)

Date of Purchase: ____________

Save this manual for future reference.

For more information, visit www.desatech.com

SAFETY INFORMATION

WARNING: This product con­tains and/or generates chemicals
known to the State of California
to cause cancer or birth defects
or other reproductive harm.

IMPORTANT: Read this owner’s
manual carefully and completely
before trying to assemble, operate
or service this heater. Improper
use of this heater can cause seri-

ous injury or death from burns, re,

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 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 ser-
viced. 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 warn-

ings. 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, 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, including the pilot light, if any,

shall be extinguished and the heater al­lowed to cool, prior to fueling.

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 sup-

ply 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 mini-

mum of 762 cm (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

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 frequency

specied on model plate.

4. Heater must be grounded. Use only a properly
grounded three-wire extension cord. Plug into
grounded outlet only.

5. Use only in areas free of ammable vapors or

high dust content.

6. Minimum clearance from any combustible
materials: 8 feet (244 cm) from hot air outlet;
6 feet (183 cm) from top; and 4 feet (120 cm)
from sides and inlet.

7. Locate heater on a stable and level surface

while hot or operating or a re may occur.

8. Use only in well-vented areas. Before using
heater, provide at least a 2800 square cm (three­square-foot) opening of fresh, outside air for
each 30 kw (100,000 Btu/Hr) of rating.

9. Keep children and animals away from heater
at all times.

10. Never start heater when combustion chamber
is hot or if fuel has accumulated in combustion
chamber.

11. When used with thermostat, heater may start
at anytime.

12. When heater is moved or stored, it must be in
a level position or fuel spillage may occur.

13. Use heater only in accordance with local
ordinances and codes.

14. Never use gasoline, crankcase drainings,
naphtha, paint thinners, alcohol or other highly

ammable fuels.

15. Never use heater where gasoline, paint thinner

or other highly ammable vapors are present.

16. Never use heater in living or sleeping areas.

17. Never leave a heater plugged in without adult
supervision if children or animals are likely to
be present.

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118637-01B2

SAFETY INFORMATION

Continued

18. Never move, handle, refuel or service a hot,
operating or plugged-in heater.

19.

Never attach duct work to front or rear of heater.

20. Never attach heater to external fuel tank.

21. 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

304.8 cm (10 feet). It is further recommended

that these enclosure materials be of a re

retardant nature. These enclosure materials
shall be securely fastened to prevent them
from igniting or from upsetting the heater due
to wind action.

22. Unplug heater when not in use.

23. Never block air inlet (rear) or air outlet (front)
of heater.

24. Warning to New York City Residents

For Use Only At Construction Sites in ac-

cordance with applicable NYC codes under

NYCFD certicate of approval #4803, #4899,

#4908, #4909 or #4934.

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.

PRODUCT IDENTIFICATION

Hot Air
Outlet

Lower
Shell

Fuel Cap/
Gauge

Upper Shell

ON/OFF
Switch

FUELS

WARNING: Use only kero­sene, #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 lter 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.

Thermostat
Knob

Handle

Fan
Guard

Extension
Cord Wrap

Shroud

Ignition Control

Control Cover

118637-01B 3

Assembly (On
Inside of Control
Cover)

Figure 1 - 125T, 170T and 200T Models

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Fuel Tank

Rear Panel

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 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 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.

Fan

Motor

Combustion Chamber

Ignitor

Air Pump

Air Intake Filter

Clean
Heated
Air Out

Fuel
Tank

Nozzle

Air For Fuel
System

Figure 2 - Cross Section Operational View

Fuel
Filter

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 associated
with carbon monoxide poisoning.
Make certain these requirements
are met prior to operating heater.

Example: A 58.6 kw (200,000 Btu/Hr) heater
requires one of the following:

• a two-car garage door [4.88 meter (16 feet)
opening] raised 12.7 cm (5 inches)

• a single-car garage door [2.74 meter (9 feet)
opening] raised 20.3 cm (8 inches)

• two, 76.2 cm (30 inch) windows raised 38.1 cm
(15 inches)

Cool Air In

Air Output Filter

Air Line
To Burner

Air For
Combustion
And Heating

Ignition Control
Assembly

Fuel

ASSEMBLY

These models are furnished with wheels and a rear
handle. Wheels, handle and the mounting hardware
are found in the shipping carton.

Tools Needed

• Medium Phillips Screwdriver

• Rubber Mallet/Hammer

• Flat Blade Screwdriver

1. Slide axle through holes in shroud. Install
washers, wheel spacers and wheels on axle
as shown in Figure 3, page 5.

IMPORTANT: When installing wheels, point

extended hub of wheels toward shroud (see
Figure 3, page 5).

2. Place cap nuts on axle ends. Gently tap with
hammer to secure.

3. Install extension cord wraps into handle.

4. Slide handle onto shroud leaving a one inch
gap between parts.

5. Place washers onto screws and insert screws
into holes in handles.

6. Visually confirm that all six screws are
threaded into the shroud. Push the handle
completely into the shroud.

7. Tighten all screws.

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118637-01B4

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ASSEMBLY

Continued

Shroud

Shroud
Axle Hole

Wheel
Spacer

Washer

Wheel

Cap Nut

Extended Hub

Axle

Figure 3 - Wheel and Handle Assembly

OPERATION

IMPORTANT: Review and under­stand the warnings in the Safety
Information section, page 2.
They are needed 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 circulation
of the heated air. Follow all location require­ments noted in Safety Information, 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, naphtha, paint thinners, alcohol or

other ammable fuels.

4. Attach fuel cap/gauge.

5. Plug heater’s 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

Air Inlet

Rear Panel

Handle

Washer

Extension
Cord Wrap

Screw

6. Plug extension cord into standard 120 volt/60
hertz, 3-prong grounded outlet.

7. Turn thermostat knob to the right (clockwise)
to the warmest position.

8. Push ON/OFF switch to the ON (|) position.
Light will come on. Note: Ignitor will preheat

for ve seconds, then heater will start.

9. After heater is running, 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

1. Push ON/OFF switch to the OFF (O) position.

2. Unplug heater.

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.

118637-01B 5

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OPERATION

Temperature
Temperatura

Thermostat
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112935-01

Continued

RL, RE AND PKHD SERIES MODELS
ONLY

Temperature Display

These models are equipped with a digital tem­perature display. The temperature being shown
represents the air nearest to the control cover. The
temperature of the air in surrounding areas may
be much different from the temperature being
displayed. The display may show [ - - ] when the
thermostat control or temperature sensor are dis­connected from the ignition control or if they are
or damaged. If this occurs, the safety control will
continue to operate as before, however, the unit
will not cycle off during operation. See Figure 4.

Lighted ON/OFF
Switch

Temperature
Display

Thermostat
Control

LED Indicator Lights

These models are equipped with LED lights in order
to help monitor your heater and to help diagnose
any potential problems associated with your heater.
Make sure you have read all of the instructions and
see Troubleshooting, page 8, before attempting to
rectify any problems with your heater.

WARNING: Never service
heater while it is plugged in,
operating or hot. Severe burns
and electrical shock can occur.

LOGIC ENHANCED IGNITION

These models have an electronically controlled
ignition system that is able to detect problems
during startup and is able to apply an automatic
“choke” to increase the likelihood of ignition. If

the heater does not ignite within the rst second

the motor will slow down momentarily. If your

heater does not light after the rst “choke” it will

repeat once. If the heater does not ignite after the
second “choke” it will shutdown and remain in
shutdown mode until the unit is reset. Please refer
to Troubleshooting, page 8 in order to properly
diagnose the problem.

Figure 4 - Control Cover with

Temperature Display

Ignitor - indicates a problem with
the ignitor and can be caused by
a damaged or broken ignitor or an
ignitor that is wired incorrectly.

Temperature
Display

Voltage - monitors line voltage during
no rmal oper a tion and indic a tes
improper line voltage. If line voltage
falls below 108V or above 132V the
heater will shut down.

Flame - will illuminate after heater
is shut down due to problems

associated with the ame or the
photocell that monitors the ame.

Figure 5 - LED Indicator Lights

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Start/Run - blin ks duri ng
“preheat” for 10-15 seconds
before ignition and will stay on
during normal operation.

118637-01B6

FUEL

F

OPERATION WITH

PORTABLE GENERATOR

WARNING: Before operating
heater or any appliance from a
portable generator, verify that
generator has been properly con­nected to earth ground. Improper
grounding or failure to ground
generator can result in electro­cution if a ground fault occurs.
Refer to owner’s manual supplied
by generator manufacturer for
proper grounding procedures.

The operating voltage range of the heater is 108 to
132 Volts (120 Volts +/- 10%). Prior to plugging
heater into generator the output voltage should be

veried (if generator is equipped with the automatic

idle feature, the output voltage should be measured
with the generator running at full speed). If the volt­age does not measure in this range the heater should
not be plugged into the generator.

Refer to Operation, page 5, for starting, stopping
and resetting heater procedures.

Alternator

Ground Lug

STORING,

TRANSPORTING OR

SHIPPING

Note: If shipping, transport companies require
fuel tanks to be empty.

1. Remove drain plug from bottom side of fuel
tank and drain all fuel.

2. Replace drain plug.

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 lters during future use.

4. Properly dispose 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.

Copper
or Brass
Grounding
Point

Ground Wire (#10 AWG

- Stranded-Copper)

Figure 6 - Typical Generator Grounding

Method (Generator construction may

vary from that shown)

118637-01B 7

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PREVENTATIVE MAINTENANCE SCHEDULE

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 operation or as needed

Clean twice a heating season or as
needed

No maintenance required
Clean every season or as needed
Not required/permanently lubricated

How To

See Storing, Transporting, or
Shipping, page 7

See Air Output, Air Intake and
Lint Filters, page 10

See Air Output, Air Intake and
Lint Filters, page 10

See Fuel Filter, page 11

See Fan, page 10

TROUBLESHOOTING

WARNING: Never service heater while it is plugged in, operating

or hot. Severe burns and electrical shock can occur.

FAULT CONDITION

Motor does not start ve seconds

after heater is plugged in
INDICATOR LIGHT

• Ignitor

POSSIBLE CAUSE

1. No power to heater

2. ON/OFF switch not in the ON
(|) position

3. Thermostat setting is too low

REMEDY

1. Check circuit breaker in elec­trical panel

2. Verify the ON/OFF switch is in
ON (|) position and light is on

3. Turn thermostat knob to a
higher setting

• Flame

WARNING: High voltage!

4. Bad electrical connector at
ON/OFF switch or thermostat

5. Blown fuse on ignition control
assembly

6. Defective ignition control
assembly

7. Bad connection between motor
and ignition control assembly

8. Binding pump rotor

9. Defective motor

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4. Check all electrical connections.
See Wiring Diagrams, page 16.
Check voltage to and from ON/
OFF switch and thermostat

5. See Ignition Control Assembly,
page 14

6. Replace ignition control
assembly

7. Check all electrical connections.
See Wiring Diagrams, page 16.

8. If fan does not turn freely, see
Pump Rotor, page 14

9. Replace motor

118637-01B8

FAULT CONDITION

Motor starts and runs but heater
does not ignite
INDICATOR LIGHT

• Flame

• Ignitor

• Voltage

Heater ignites but ignition control
assembly shuts heater off after a
short period of time
INDICATOR LIGHT

• Flame

TROUBLESHOOTING

Continued

POSSIBLE CAUSE

1. No fuel in tank

2. Pump pressure incorrect

3. Dirty fuel filter

4. Obstruction in nozzle

5. Water in fuel tank

6. Air or fuel line disconnected

WARNING: High voltage!

7. Bad elec trical connection
between ignitor and ignition
control assembly

8. Defective ignitor

9. Defective ignition control as­sembly

10.

Line voltage is below 108V or

above 132v

11.

Bad ground on circuit

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

REMEDY

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 ush fuel tank with

clean kerosene. See Stor ing,
Transporting or Shipping, page 7

6. Reconnect lines (see Fuel and
Air Lin e Repl ac em ent and
Proper Routing, page 13)

7. Check electrical connections.
See Wiring Diagrams, page 16

8. Replace ignitor, see page 11

9. Replace ignition control as­sembly

10.

Check for proper line voltage

11.

Check all grounds

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

WARNING: High voltage!

• Voltage

118637-01B 9

7. Bad electrical connection be­tween photocell and ignition
control assembly

8. Defective photocell

9. Defective ignition control

assembly

10.Line voltage is below 108V or
above 132v

www.desatech.com

7. Check electrical connections.
See Wiring Diagrams, page 16

8. Replace photocell

9. Replace ignition control as­sembly

10.Check for proper line voltage.
Disconnect power equipment
that may be used on same
line

SERVICE PROCEDURES

2

1

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
phillips screwdriver. These screws attach upper
and lower shells together. See Figure 7.

2. Lift upper shell off.

3. Remove fan guard.

Screw

Figure 7 - Upper Shell Removal

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 8).

1. Remove upper shell (see Figure 7).

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 9).

7. Place setscrew on flat of shaft. Tighten setscrew
firmly (40-50 inch-pounds/4.5-5.6 n-m).

8. Replace upper shell.

Setscrew

Fan

Upper Shell

Setscrew

Motor

Fan

AIR OUTPUT, AIR INTAKE AND LINT
FILTERS

1. Remove upper shell (see Figure 7).

2. Remove filter end cover screws using 5/16"
nut-driver (see Figure 10).

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 8).

6. Replace filter end cover.

7. Replace upper shell.

IMPORTANT: Do not oil filters.

Air Intake
Filter

Filter
End
Cover

Lint Filter

Air Output Filter

Figure 10 - Air Output, Air Intake and Lint

Filters

PUMP PRESSURE ADJUSTMENT

1. Remove fan guard using medium phillips
screwdriver.

2. Remove pressure gauge plug from filter end
cover (see Figure 11).

3. Install accessory pressure gauge (part number
HA1180).

4. Start heater (see Operation, page 5). Allow
motor to reach full speed.

Relief
Valve

Pressure
Gauge
Plug

Motor Shaft

Figure 8 - Fan, Motor

Shaft and Setscrew

Location

Motor
Shaft

Figure 9 - Fan

Cross Section

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Flush

Figure 11 - Pressure Gauge Plug

Removal

118637-01B10

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SERVICE PROCEDURES

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Continued

5. Adjust pressure. Turn relief valve to right to
increase pressure. Turn relief valve to left to
decrease pressure. See specifications below
for correct pressure (see Figure 12).

6. Remove pressure gauge. Replace pressure
gauge plug in filter end cover.

7. Replace fan guard.

Pump

Model Pressure

125T 6.0 PSI
170T 6.0 PSI
200T 6.2 PSI

Figure 12 - Adjusting Pump Pressure

FUEL FILTER

1. Unplug heater.

2. Remove control cover screws using medium
phillips screwdriver.

3. Remove control cover.

4. Pull upper fuel line off fuel filter neck (see
Figure 13).

5. Carefully pry bushing, fuel filter and lower
fuel line out of fuel tank (see Figure 13).

6. Wash fuel filter with clean fuel and replace in
tank.

7. Attach upper fuel line to fuel filter neck.

8. Replace control cover.

Control Cover

Fuel Filter,
Bushing and
Lower Fuel Line

Upper Fuel Line

Pressure
Gauge

Screw

WARNING: HIGH VOLTAGE

WARNING: To avoid risk of burn
and electrical shock, never at­tempt to service heater while it is
plugged in, operating or hot.

IGNITOR

1. Remove upper shell (See Upper Shell Re­moval, page 10).

2. Remove fan (see page 10).

3. Remove 2 control cover screws with a phil­lips screwdriver. Remove control cover (see
Figure 13).

4. Disconnect ignitor wires from ignition control
assembly (see Figure 14). Pull the ignitor
wires up through the hole in the lower shell.

5. Disconnect fuel line hose and air line hose.
Remove photocell from photocell bracket (see
Figure 14).

6. Remove combustion chamber. Stand com­bustion chamber on end with nozzle adapter
bracket on top (see Figure 15, page 12).

7. Remove ignitor screw with a 1/4" nut driver
for models using ignitor HA1000 or 5/16"
nut driver for models using ignitor HA1100.
Carefully remove ignitor from nozzle adapter
bracket.

8. Carefully remove replacement ignitor from
styrofoam packing.

Combustion
Chamber

Air Line Hose

Photocell
Bracket

Fuel Line
Hose

Photocell
Assembly

Nozzle Adapter
Bracket

Ignitor

Ignitor
Wire

Ignitor
Wire

Ignition

Control Cover

Control
Assembly

Figure 14 - Disconnecting Ignitor Wires

from Ignition Control Assembly

Figure 13 - Fuel Filter Removal

118637-01B 11

www.desatech.com

(170T Model Shown)

SERVICE PROCEDURES

Continued

CAUTION: Do not bend or
strike ignitor element. Handle
with care.

9. Carefully guide ignitor into opening in nozzle
adapter bracket. Do not strike ignitor element.
Attach ignitor to nozzle adapter bracket with
screw using a 1/4" nut driver for models using
ignitor HA1000 (see Figure 15) or 5/16" nut
driver for models using HA1100 ignitor (see
Figure 16). Torque .90 to 1.69 N-m (8 to 15
in-lbs) Do not over torque.

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 (see Figure 14,
page 11).

12.

Replace control cover (see Figure 13, page 11).

13. Connect and route fuel line hose and air line
hose to nozzle adapter assembly. See Fuel and
Air Line Replacement and Proper Routing,
page 13.

14. Replace photocell in photocell bracket. Route
wires as shown in Figure 17.

15. Replace fan (see page 10).

16. Replace upper shell (see page 10).

Ignitor Screw/Washer
Assembly

Ignitor

Ignitor Element
Photocell
Bracket

Nozzle
Adapter
Bracket

Ignitor

Ignitor Element

Photocell
Bracket

Nozzle Adapter
Bracket Opening

Figure 16 - Ignitor HA1100 Replacement

Nozzle
Adapter
Bracket

Combustion
Chamber

NOZZLE ASSEMBLY

125T and 170T Models Only

1. Remove upper shell (see Upper Shell Re­moval, page 10).

2. Remove fan (see Fan, page 10).

3. Remove fuel and air line hoses from nozzle
assembly (see Figure 17).

4. Turn nozzle assembly 1/4 turn to left and pull
toward motor to remove (see Figure 18).

Combustion
Chamber

Nozzle
Adapter
Bracket

Photocell
Bracket

Nozzle/
Adapter
Assembly

Fuel Line
Hose

Combustion
Chamber

Figure 15 - Ignitor HA1000 Replacement

Nozzle Adapter
Bracket Opening

www.desatech.com

Air Line Hose

Figure 17 - Removing Air and Fuel Line

Hoses (125T and 170T Models Only)

Combustion
Chamber

Figure 18 - Removing Nozzle/Adapter

Assembly

Nozzle/
Adapter
Assembly

118637-01B12

SERVICE PROCEDURES

Continued

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 19).

7. Blow compressed air through face of nozzle.
This will free any dirt in nozzle area.

8. Inspect nozzle sleeve for damage.

9. 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-lbs).
See Figure 19).

10. Attach nozzle assembly to nozzle adapter
bracket (see Figure 18, page 12).

11. Attach fuel and airline hoses to nozzle as­sembly. See Fuel and Airline Replacement
and Proper Routing.

12. Replace fan (see Fan, page 10).

13. Replace upper shell (see Upper Shell Removal,
page 10).

Nozzle Face

Nozzle

Air Line Fitting

Fuel Line Fitting

Figure 19 - Nozzle and Nozzle Adapter

200T Model Only

1. Remove combustion chamber and ignitor by
following steps 1 through 7 under Ignitor,
page 11.

2. Carefully place the ignitor in a safe location.

3. Remove two nozzle adapter bracket screws
(see Figure 20).

4. Place hex-shaped aluminum nozzle adapter
into vise (do not overtighten).

5. Carefully remove nozzle from nozzle adapter
using 5/8" socket wrench (see Figure 21).

6. Blow compressed air through face of nozzle.
This will remove any debris in nozzle.

7. Inspect nozzle seal for damage.

8. Replace nozzle into nozzle adapter until
nozzle seats. Tighten 80-110 inch-pounds.

9. Attach nozzle adapter bracket to combustion
chamber with two screws removed in step 3.

10. Repeat steps 9 through 16 under Ignitor,
page 11.

Nozzle Sleeve

Nozzle
Adapter

Combustion
Chamber

Nozzle
Adapter
Bracket

Photocell
Bracket

Air Line
Hose

Figure 20 - Replacing Air and Fuel Line

Hoses (200T Model Only)

Nozzle Face

Nozzle

Nozzle
Adapter
Bracket

Figure 21 - Nozzle and Nozzle Adapter

Nozzle
Sleeve

Air Line
Fitting

Nozzle/
Adapter
Assembly

Fuel Line Hose

Nozzle
Adapter

Fuel Line
Fitting

FUEL AND AIR LINE REPLACEMENT
AND PROPER ROUTING

1. Remove upper shell (see Upper Shell Re­moval, page 10).

2. Remove control cover screws using phillips
screwdriver (see Figure 13, page 11).

3. Remove control cover.

4. Inspect fuel and air line hoses for cracks and/or
holes. If fuel line hose is damaged, disconnect
from nozzle adapter (see Figure 17, page 12 or
Figure 20 according to model) and from fuel
filter (see Fuel Filter, page 11). If air line hose
is damaged, disconnect from nozzle adapter
(see Figure 17, page 12 or Figure 20 according
to model and from barb fitting on pump end
cover (see Figure 22, page 14).

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, page 14) and the other
end to nozzle adapter (see Figure 17, page 12
or Figure 20 according to model). Attach one
end of fuel line hose to fuel filter (see Fuel
Filter, page 11) and the other end to nozzle
adapter (see Figure 17, page 12 or Figure 20
according to model).

118637-01B 13

www.desatech.com

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SERVICE PROCEDURES

Continued

Note: Route hoses as shown in Figure 17, page

12 or Figure 20 according to model. Hoses are
not to touch photocell bracket.

6. Replace control cover.

7. Replace upper shell (see Upper Shell Removal,
page 10).

Pump End
Cover

Air Hose

Figure 22 - Air Hose to Barb Fitting

PUMP ROTOR
(Procedure if Rotor is Binding)

1. Remove upper shell (see Upper Shell Re­moval, page 10).

2. Remove fan guard.

3. Remove filter end cover screws using 5/16"
nut driver (see Figure 23).

4. Remove filter end cover and air filters.

5. Remove pump plate screws using 5/16" nut­driver.

6. Remove pump plate.

7.

Remove rotor, insert and blades (see
Figure 23).

8. Check for debris in pump. If debris is found,
blow out with compressed air.

9. Install insert and rotor.

10. Check gap on rotor. Adjust to 0.076/0.101 mm
(0.003"/0.004") if needed (see Figure 24).

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.

11. Install blades, pump plate, air filters and filter
end cover.

12. Replace fan guard and upper shell (see Upper
Shell Removal, page 10).

13. Adjust pump pressure (see Pump Pressure
Adjustment, page 10).

Note: If rotor is still binding, proceed as follows.

14. Perform steps 1 through 6.

15. Place fine grade sandpaper (600 grit) on flat
surface. Sand rotor lightly in “figure 8” motion
four times (see Figure 25).

16. Reinstall insert and rotor.

17. Perform steps 10 through 12.

Barb
Fitting

www.desatech.com

Pump Plate

Blade

Air
Intake
Filter

Filter End
Cover

Insert

Rotor

Air Output Filter

Figure 23 - Rotor Location

Gap Adjusting Screw

0.003"/0.004"
(0.076-0.101 mm)
Gap Measured
With Feeler
Gauge

Rotor

Blade

Gap Adjusting Screw

Figure 24 - Gap Adjusting Screw

Locations

Sandpaper

Figure 25 - Sanding Rotor

IGNITION CONTROL ASSEMBLY

WARNING: High voltage!

1. Unplug heater.

2. Remove control cover screws (2) using phil­lips screwdriver to expose ignition control
assembly (see Figure 11, page 10).

3. Remove fuse from fuse holder.

4. Replace with new fuse (DESA Heating Prod­ucts part number 118747-01). Do not substitute
a fuse with a higher current rating. Use an
equivalent 2 amp, 5 x 20 mm fuse.

5.

Replace control cover (see Figure 11,
page 10).

Fuse Holder

Fuse

Figure 26- Replacing Fuse

118637-01B14

SPECIFICATIONS

125T Models

• Output Rating: 125,000 Btu/Hr

• Fuel: Use only kerosene, #1/#2 diesel/fuel oil, JET A or JP-8 fuels*

• Fuel Tank Capacity: 13.5 gal (51 liters)

• Fuel Consumption per Hr: 0.90 gal (3.41 liters)

• Pump Pressure (psi): 6.0

• Electric Requirements: 120 V/60 HZ

• Amperage (Normal Run): 3.6

• Maximum Motor Speed (RPM): 3400

• Hot Air Output (CFM): 520

• Motor Horsepower: 1/5

• Shipping Weight (Approx.): 81 lb (36.74 kg)

• Heater Weight without Fuel (Approx.): 73 lb (33.11 kg)

170T Models

• Output Rating: 170,000 Btu/Hr

• Fuel: Use only kerosene, #1/#2 diesel/fuel oil, JET A or JP-8 fuels*

• Fuel Tank Capacity: 13.5 gal (51 liters)

• Fuel Consumption per Hr: 1.25 gal (4.73 liters)

• Pump Pressure (psi): 6.0

• Electric Requirements: 120 V/60 HZ

• Amperage (Normal Run): 3.6

• Maximum Motor Speed (RPM): 3400

• Hot Air Output (CFM): 580

• Motor Horsepower: 1/5

• Shipping Weight (Approx.): 82/37.2 kg)

• Heater Weight without Fuel (Approx.): 74 lb (33.57 kg)

200T 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 liters)

• Fuel Consumption per Hr: 1.4 gal (5.3 liters)

• Pump Pressure (psi): 6.2

• Electric Requirements: 120 V/60 HZ

• Amperage (Normal Run): 3.6

• Maximum Motor Speed (RPM): 3400

• Hot Air Output (CFM): 600

• Motor Horsepower: 1/4

• Shipping Weight (Approx.): 87 lb (39.46 kg)

• Heater Weight without Fuel (Approx.): 79 lb (35.86 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.

118637-01B 15

www.desatech.com

Power Plug

120V/60Hz

Blue

Blue

White

Photocell

Ignition Control Assembly

113471-01

Green

Black

Green

Red

Black

Yellow/Tan

Yellow/Tan

Motor

Ignitor

Photocell

Photocell

Ignitor

Temp.

Temp.

Motor Return

AC Neutral (L2)

120V (L1)

Ignitor

Motor

White

ON/OFF Switch

with Light

5

4

1

Thermostat
Control

Temperature
Sensor

Power Plug

120V/60Hz

Blue

Blue

White

Photocell

Ignition Control Assembly

Green

Black

Black

Green

Red

Black

Yellow

Yellow

Motor

Ignitor

Thermostat

Photocell

Photocell

Ignitor

Motor Return

AC Neutral (L2)

120V (L1)

Ignitor

Motor

White

ON/OFF Switch

with Light

5

4

1

WIRING DIAGRAMS

MODELS RH125AT, M125AT, RH170AT, M170AT, M200AT AND TA110 ONLY

125T MODEL: RE125AT
170T MODELS: RL170AT, RE170AT, PKHD170T
200T MODEL: PKHD200T

www.desatech.com

118637-01B16

TECHNICAL SERVICE

You may have further questions about installation,
operation or troubleshooting. If so, contact DESA
Heating Products’ Technical Service Department
at 1-866-672-6040. When calling please have your
model and serial numbers of your heater ready.

You can also visit DESA Heating Products’ techni­cal services web site at www.desatech.com.

REPLACEMENT PARTS

Note: Use only original replacement parts. This
will protect your warranty coverage for parts
replaced under warranty.

PARTS UNDER WARRANTY

Contact authorized dealers of this product. If they
can’t supply original replacement part(s), call
DESA Heating Products’ Technical Service Dept.
at 1-866-672-6040.

When calling DESA Heating Products, have
ready:

• your name

• your address

• model and serial numbers of your heater

• how heater was malfunctioning

• purchase date
Usually, we will ask you to return the part to the

factory.

PARTS NOT UNDER WARRANTY

Contact authorized dealers of this product. If they
can’t supply original replacement part(s), call
DESA Heating Products at 1-866-672-6040 for
referral information. Parts dealers are listed in
the Authorized Service Center booklet supplied
with heater.

When calling DESA Heating Products, have
ready:

• model and serial numbers of your heater

• the replacement part number

ACCESSORIES

Purchase accessories and parts from your nearest
dealer or service center. If they can not supply
these accessories or parts, either contact your
nearest parts dealer or DESA Heating Products
at 1-866-672-6040 for referral information. Parts
Centrals are listed in the Authorized Service Center
booklet supplied with heater.

AIR GAUGE KIT - HA1180

For all model s. Special tool to check pump
pressure.

IGNITION CONTROL ASSEMBLY/
PHOTOCELL TESTER - HA1170

For all models. Special tool used to test the igni­tion control assembly and photocell.

118637-01B 17

www.desatech.com

ILLUSTRATED PARTS BREAKDOWN

1

13

3

23

19

9

10

11

12

15

25

13

24

29

30

31

33

32

26

14

13

16

2

34

23

5

4

6

18

7

8

35

27

20

22

21

28

36

17

125T MODELS: RH125AT, M125AT, RE125AT, TA110
170T MODELS: RH170AT, RL170AT, M170AT, RE170AT, PKHD170T

www.desatech.com

118637-01B18