Toyotomi Toyoset NS-2800 User manual

SERVICE MANUAL
CABIN HEATER
MODEL NS-2800
TOYOTOMI CO., LTD.
NAGOYA JAPAN

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Table of Contents
Section 1: Description
1-1. Introduction …………………………………………………………… 5
1-2. Physical Specifications ……………………………………………… 5
1-3. Description of Functions ……………………………………………. 5
1-4. Components ………………………………………………………… 6
1-5. Combustion System ………………………………………………… 6
1-6. Heat Chamber ………………………………………………………… 7
1-7. Burner ………………………………………………………………… 7
1-8. Burner Ring …………………………………………………………… 7
1-9. Burner Mat …………………………………………………………… 7
1-10. Burner Thermistor …………………………………………………… 7
1-11. Flame Sensor (Flame Rod) ………………………………………… 7
1-12. Igniter ………………………………………………………………… 7
1-13. Forced Flue Vented System ………………………………………… 8
1-14. Flue Pipe ……………………………………………………………… 8
1-15. Blower Motor Assembly …………………………………………… 8
1-16. Heat Exchanger ……………………………………………………… 8
1-17. Fuel Delivery System ………………………………………………… 8
1-18. Fuel Tank ……………………………………………………………… 9
1-19. Solenoid Fuel Pump ………………………………………………… 9
1-20. Electrical System …………………………………………………… 9
1-21. Control Circuit Board ……………………………………………… 9
1-22. Temperature Sensor ………………………………………………… 9
1-23. Safety Mechanism …………………………………………………… 9
1-24. Power Failure Recovery System …………………………………… 9
1-25. Fuse …………………………………………………………………… 9
1-26. Overheat Protector Switch (High Limit Switch)…………………… 10
Section 2: Installation
2-1. Introduction …………………………………………………………… 11
2-2. Physical Placement of Heater ……………………………………… 11
2-3. Power Requirement ………………………………………………… 11
2-4. Fuel Tank Requirements …………………………………………… 11
2-5. Building and Boat Safety Codes …………………………………… 12
2-6. Unpacking …………………………………………………………… 12
2-7. Installing Extension Kit ……………………………………………… 12
2-8. Fuel Tank Installation ………………………………………………… 13

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Section 3: Operation
3-1. Introduction …………………………………………………………… 14
3-2. Operating Specifications …………………………………………… 14
3-3. Operating Controls and Monitor Lamps ………………………… 15
3-4. Operation ……………………………………………………………… 16
3-5. Turning Heater Off …………………………………………………… 16
3-6. Room Temperature Sensor ………………………………………… 16
3-7. Power Failure Recovery …………………………………………… 17
3-8. Overheat Recovery …………………………………………………… 17
3-9. Automatic Cleaning Cycle …………………………………………… 17
Section 4: Maintenance
4-1. Introduction …………………………………………………………… 18
4-2. Routine Maintenance ………………………………………………… 18
4-3. Inspection of Exhaust/Air Lines …………………………………… 19
4-4. Verification of Igniter Operation …………………………………… 19
4-5. Fuel Contamination ………………………………………………… 20
Section 5: Component Specifications and Adjustments
5-1. Main Circuit Board …………………………………………………… 21
5-2. Igniter ………………………………………………………………… 21
5-3. Burner Thermistor …………………………………………………… 21
5-4. Fuel Pump …………………………………………………………… 22
5-5. Burner Mat …………………………………………………………… 22
5-6. High Limit Switch …………………………………………………… 23
5-7. Blower Motor ………………………………………………………… 23
Section 6: Troubleshooting Guide
6-1. Troubleshooting Guide I …………………………………………… 24
6-2. Troubleshooting Guide II …………………………………………… 26
6-3. Troubleshooting Guide III …………………………………………… 27
6-4. Troubleshooting Guide IV …………………………………………… 28
6-5. Troubleshooting Guide V …………………………………………… 30
6-6. Troubleshooting Guide VI ………………………………………… 31
6-7. Troubleshooting Guide VII ………………………………………… 32

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Section 7: Disassembly Procedure
7-1. Introduction …………………………………………………………… 34
7-2. Cabinet and Panels ………………………………………………… 34
7-3. Igniter ………………………………………………………………… 35
7-4. Fuel Pipe ……………………………………………………………… 35
7-5. Fuel Nozzle …………………………………………………………… 35
7-6. Fuel Pump …………………………………………………………… 36
7-7. Fuse …………………………………………………………………… 36
7-8. Transistor ……………………………………………………………… 36
7-9. High Limit Switch …………………………………………………… 36
7-10. Main Circuit Board …………………………………………………… 37
7-11. Heat Exchanger ……………………………………………………… 37
7-12. Heat Chamber and Flame Rod ……………………………………… 38
7-13. Burner Ring …………………………………………………………… 39
7-14. Burner Mat …………………………………………………………… 39
7-15. Burner Assembly …………………………………………………… 39
7-16. Burner Thermistor …………………………………………………… 39
7-17. Blower Motor Assembly …………………………………………… 40
Section 8: Circuit Board Specifications
8-1. Wiring Diagram ……………………………………………………… 42
8-2. Time Chart …………………………………………………………… 43
Section 9: Parts Description
9-1. Exploded View ………………………………………………………… 44
9-2. Parts List ……………………………………………………………… 45
9-3. Accessories …………………………………………………………… 46

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Section 1: Description
1-1. Introduction
The Laser Heating System is a completely new type of sophisticated and fuel-efficient
vented system featuring its own housing, combustion and air circulation system and a
microcomputer control system.
In addition to superior design and technology, serious testing for quality and safety has
made the Laser Heating System unmatched for efficiency, convenience, economy and
flexibility. Plus, the Laser is easy to maintain and requires minimal service.
The following section outlines the Laser Heater and its various components.
1-2. Physical Specifications
Listed below are the physical specifications that apply to the CABIN HEATERS.
Model: NS-2800
Dimensions (WxDxH): 410 mm x 190 mm x 315 mm (16-1/8”x7-1/2”x12-3/8”)
Weight: 9.0 kg (20 lbs.)
Flue Pipe: Outer nominal: 50 mm (2 in.)
Inner nominal: 25 mm (1 in.)
1-3. Description of Functions
Fuel is delivered by the solenoid fuel pump to the burner assembly through the fuel
nozzle. Simultaneously air is delivered by the blower fan to the burner assembly through
small holes located on the inside burner wall. At the starting, the igniter heats up and
vaporizes the incoming fuel and results in ignition. Once combustion has started, it
continues in the heated burner as long as fuel supply continues.
The blower motor also drives the circulation fan to blow air through the heat exchanger
and therefore, cool air comes out from air outlet for a short time.
Once it reaches to the desired cabin temperature, the heater turns to the low mode. The
heater will run at three stages “HIGH”, “LOW”and “OFF”to maintain the desired
temperature setting.

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1-4. Components
The cabin heater is composed of the following:
1-5. Combustion System
The combustion system maintains the room temperature at the desired temperature.
In the combustion system a mixture of fuel and air is burned to produce heat. Air is
drawn from outside the dwelling to the burner. At the same time, fuel is metered from a
storage tank into this same burner. Within the burner, the air/fuel mixture is ignited to
produce heat.
The Laser combustion system is safeguarded by an overheat protector switch (high limit
switch) that will shut down the heater (to protect it from damage) in the event of
excessive heat build-up. The overheat protector switch will be reset after the cooling
down period. Then push in the HEAT switch to “ON”position again to restart.

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1-6. Heat Chamber
The combustion assembly consists of two main parts; one is the heat chamber and the
other is the burner. The heat chamber is a cylinder which is secured to the burner. The
heat chamber has a window, allowing the serviceman to visually examine the
combustion process (i.e. glowing igniter coil or proper flame). The heat exchanger is
connected to the top of the heat chamber.
The burner is positioned on the cabinet base. Connected to the burner are the igniter
(located within the burner) and a fuel line. Within the burner are the burner ring and
burner mat. An airway in the cabinet base channels air from the intake fan of the
combustion blower to the base of the burner. The flame sensor is mounted through the
wall of the heat chamber.
1-7. Burner
The burner has double wall construction and contains an igniter tube, a fuel inlet fitting
and a series of air holes on the inner wall.
1-8. Burner Ring
This part is designed to promote efficient burning. The burner ring is held by spring clips
to mounting posts within the burner.
1-9. Burner Mat
The burner mat ensures even vaporization of the fuel for proper burning.
1-10. Burner Thermistor
The burner thermistor checks the burner temperature for proper burning.
1-11. Flame Sensor (Flame Rod)
The flame sensor checks the condition of the flame for proper burning.
1-12. Igniter
The coil type igniter is designed to vaporize and ignite the air/fuel mixture to start the
combustion process.

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1-13. Forced Flue Vented System
The combustion air system channels air to and from the heater. Outside air is drawn into
the heater by the combustion blower through the flue pipe and is blown into the bottom
of the burner. It then combines with the vaporized fuel and ignites.
As the heated air passes through the heat exchanger, a blower fan blows air past the
heat exchanger and out again into the room from the heated air outlet.
1-14. Flue Pipe
The flue pipe assembly is a “pipe-within-a-pipe”design which consists of two concentric
tubes. Outside air is drawn through the cylindrical space between the tubes. Combustion
by-products are vented through the inner tube. As cool air enters the flue pipe, it is
heated by the hot air that is exiting the system.
1-15. Blower Motor Assembly
The blower motor assembly on the cabin heater is a dual function fan with the intake air
and circulation fans mounted on a common shaft. One side is the intake air fan and the
other is the circulation fan. The intake fan draws in outside air through the flue pipe for
internal combustion. The cabin heater blower motor has a two-stage speed fan. The
larger diameter intake fan keeps the air pressure within combustion system lower than
the room air. The operation modes control the fan speeds and the solenoid fuel pump.
The blower motor will keep running for 120 seconds after turning off the heater to
exhaust vapor gas in the system and cool down the unit.
1-16. Heat Exchanger
The exhaust vapors pass through the heat exchanger and are pushed out through the
flue pipe by the pressure generated by the blower motor. While exhaust vapors are
moving through the heat exchanger, the heat is forced to be conducted to the circulation
air by the air circulation fan.
1-17. Fuel Delivery System
Fuel is pumped up from the external fuel storage tank or the removable fuel tank to the
burner.
The solenoid fuel pump meters the flow of fuel to the burner through a copper fuel line.

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1-18. Fuel Tank
The tank should contain a fuel strainer and a vent.
1-19. Solenoid Fuel Pump
The solenoid fuel pump is located on the bottom part of the unit.
1-20. Electrical System
All electronic diagrams, such as the wiring diagram, the circuit board layout, and the
electrical schematic can be found in this service manual.
1-21. Control Circuit Board
The control circuit board provides safety timings, controls relays and provides thermostat
functions for the cabin heater. A component layout of the printed circuit board is found in
this service manual.
1-22. Temperature Sensor
The room temperature sensor, which is capable of sensing room temperature within a
range of 0 to 30°C (32 to 85°F), can be wall mounted.
Approximately 2.5 m (8-1/5 ft.) of wire is supplied with sensor to facilitate wall mounting
in a favorable location.
1-23. Safety Mechanism
Several safety mechanisms have been built into the Laser Heating System. These
devices protect the user against personal injury, protect the heater against damage, and
shut down the heater if a malfunction occurs.
1-24. Power Failure Recovery System
When an electric power failure occurs while the heater is in operation, the heater will
automatically re-start after the power is restored.
1-25. Fuse
In the event of a power surge or internal wiring hazards, the fuse will open and power to
the heater will be cut off. The fuse is rated at 10 Amps.

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1-26. Overheat Protector Switch (High Limit Switch)
This switch is rated at 90°C (195°F). Should the heater overheat (internal temperature
rises beyond 90°C (195°F)), the overheat protector switch (also called a high limit
switch) will open to shut off the heater. The power lamp will simultaneously flash. The
overheat protector switch will automatically reset after the heater has cooled down.
Once the heater has cooled to 70°C (160°F), the system can be restarted manually as
follows.
1. Push in the HEAT switch to “OFF” position.
2. Allow heater to cool down.
3. Resolve the cause of the overheat.
4. Push in the HEAT switch to “ON”position.
The heater will continue operation again.

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Section 2: Installation
2-1. Introduction
This section contains all relevant installation information including;
- Installation specifications
- Alternative types of venting systems and installation procedures for each
- Basic requirements for fuel tank installation
The heater can be located almost anywhere within the dwelling provided that electrical,
fuel and exhaust specifications are met.
- IMPORTANT -
Before beginning installation of the cabin heater (including any electrical wiring and fuel
supply equipment), check local building, boat, electrical, mechanical and fire codes. The
requirement of these codes must be followed to insure lawful installation and use.
2-2. Physical Placement of Heater
In addition to the space taken up by the heater, interior space must also be reserved for
free air circulation. Remove all combustibles from the heating area.
Unless building, boat or fire codes dictate otherwise, the cabin heater can be placed on
any floor surface or wall (including carpeting or other combustible materials) and provide
safe operation.
2-3. Power Requirement
This model runs with the power supply rated at DC 12V.
- IMPORTANT -
Be sure to connect the power supply cord according to the plus (+) and minus (-)
markings.
2-4. Fuel Tank Requirements
The fuel must be stored in the clean individual fuel tank or engine fuel tank.

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- WARNING -
Installation of any fuel tank must comply with all local standards, building and/or boat
safety codes.
2-5. Building and Boat Safety Codes
Fire regulations, local building codes, and boat safety codes may govern the installation
and use of a vented heater and related fueling systems. Prior to installation, check and
comply with all codes.
2-6. Unpacking
Save all shipping materials until the heater has been completely installed and is working
properly.
A. Take the Owner’s Manual out of the shipping carton.
B. Remove the fuel tube from the side of the carton.
C. Remove the installation kit box from the shipping carton.
D. Firmly hold the cabinet and lift the heater from the shipping carton.
E. Remove the plastic bag covering the heater.
F. Remove the plastic bag containing the heater parts from the installation kit
box and set it aside.
G. Check for parts as listed in the Owner’s Manual.
- IMPORTANT -
Only the standard accessories and attachments are shipped with the heater. The
TOYOSET dealers/distributors will also stock other accessories and parts that may be
required for a non-standard installation.
2-7. Installing Extension Kit
Installing an extension pipe kit requires the use of an intake pipe and the exhaust pipe.
The exhaust pipe is connected to inner pipe and the intake pipe is connected to outer
pipe of the flue pipe.
- IMPORTANT -
The total length of an extension pipe between heater and flue pipe must be no longer
than 1.5 m (5 ft.) and no more than two (2) bends may be used.

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2-8. Fuel Tank Installation
Fuel tank installation is illustrated below. Since fuel tank installation techniques vary from
place to place, use the following check list as a guide to the fuel storage facilities.
1. The fuel supply tube must be shorter than 1.5 m (5 ft.).
2. Piping should include no inverse U-type bends (to avoid air locks, which could
block the fuel supply).
3. A fuel strainer must be used to avoid fuel pump failure.
21 Fuel pipe (Part #17185654)
22 Insert cap nut (Part #17185330)
23 Sleeve (Part #17185335)
24 Strainer (Part #17185336)

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Section 3: Operation
3-1. Introduction
The NS-2800 is an easy-to-operate vented heater. Routine operation features automatic
adjustment of room temperature, low fuel and power consumption. This section provides
all information necessary to operate the Laser Heating System. All operation procedures
specified should be performed in the order in which they are described.
3-2. Operating Specifications
The following specifications apply to the operation of the NS-2800.
Model: NS-2800
Type: Forced Flue (FF) type
Ignition Type: Electric Lighting (Coil Heater)
Fuel Type: Kerosene or Diesel Oil
(No.1 Fuel Oil in the U.S. and Canada)
Heat Rating: High: 2,300 kcal/h (2,675 w/h, 9,800 BTU/h)
Low: 1,150 kcal/h (1,335 w/h, 4,900 BTU/H)
Fuel Consumption: High: 0.28 L/h (0.07 gal/h)
Low: 0.14 L/h (0.04 gal/h)
Heating Efficiency: Approx. 90%
Power Source: DC 12V
Power Consumption: Ignition: 96 W (3 minutes)
Burning: High: 27 W, Low: 17W
Normal Operating Current:
High: 2.3 A, Low: 1.4 A
Current Fuse: 10 Amp.
Safety Devices: Ignition safety device
Flame sensor
Overheat protector switch (High limit switch)
Power failure safety device
Burner temperature sensor
Low/High/Reverse power voltage safety device
Flue Pipe (Pipe-in-pipe structure):
Inner nominal: 25 mm (1 in.) diameter
Outer nominal: 50 mm (2 in.) diameter
Air Duct: 65 mm (2-3/16 in.) or 75 mm (3 in.) diameter
Ventilation Capacity:
Approx. 78 cubic meter/h (2,700 CFT/h)
(High mode without extension pipe)

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3-3. Operating Controls and Monitor Lamps
The remote control switch is used to operate the
heater and allow the user to monitor its
performance.
(1) HEAT Switch:
In the “ON”position, the heater begins its operation. The power monitor lamp will
be lit. At the “OFF”position, the heater will turn off and all lamps go out.
(2) VENT Switch:
When the VENT switch is in “ON”position, only the blower motor operates for
ventilation.
(3) Temperature Selector:
The room temperature can be set from 10 to 30 °C (50 to 85 °F).
(4) Monitor Lamps:
These lamps indicate conditions of operation and warnings.
Malfunction
POWER
(YELLOW)
FLAME
(RED)
VENT
(GREEN
)
High limit switch activated. O
Room temp. sensor malfunction or disconnect. O
Ignition safety device activated.
Flame sensor activated.
O
Igniter coil broken.
Power voltage is too high. (12Vmore than 17V) O O
Power voltage is too low. (12Vless than 10V)
Abnormal revolution.
Power voltage is too low.
Ignition coil deformed.
O O O
Burner temp. sensor activated. O O

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3-4. Operation
Push in the HEAT switch to the “ON”position. (Vent switch is “OFF”position.) The
power monitor lamp will be lit and the igniter will glow red. 12 seconds later the blower
motor and the fuel pump start in the low mode.
The blower motor repeats the process with 17.5 seconds of operation and 2.5 seconds
off until combustion starts when the flame lamp is lit. This process ensures ignition. After
the flame lamp is lit, the blower motor will continue operation.
In the meantime, the fuel pump delivers fuel to the burner continuously. 30 seconds after
the flame lamp is lit, the fuel pump stops for 20 seconds to consume the excess fuel in
the burner.
Igniter will turn off 130 seconds after the flame lamp is lit.
2 minutes and 50 seconds after ignition, the flame sensor is activated. If the flame is
detected, operation will continue and the flame lamp will remain lit. If not, the heater is
extinguished and the flame lamp will flash.
The heater operates at “LOW”combustion for 5 minutes after the flame is detected,
regardless of temperature setting. After this period, the heater will run at three stages,
“HIGH”, “LOW”and “OFF”cycle to maintain the desired temperature.
3-5. Turning Heater Off
Push in the HEAT switch to “OFF”position. The circulation and blower motor fans
continue to run for two minutes in order to cool heater down.
3-6. Room Temperature Sensor
A room temperature sensor is provided with approx. 2.5 m (8-1/5 ft.) of extension wire.
The room temperature sensor can be installed with the self adhesive tape on the back or
with the wood screw provided with the sensor, depending on the type of surface chosen
for installation.
- NOTE -
Choose an installation location for the sensor that is not in the path of direct sunlight,
drafts or the flow of warm air from the heater.

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3-7. Power Failure Recovery
When an electric power failure occurs while the heater is in operation, all electrical
systems will be automatically shut off. When the power is restored, the heater
automatically reignites and operates.
3-8. Overheat Recovery
The heater is protected against damage resulting from an overheat condition by 90°C
(195°F) automatic reset thermostat (overheat protector switch).
In the event of an overheat, the overheat protector is triggered to shut the heater off.
STEP 1: Turn the heater off to cool down the heater.
STEP 2: Be sure that the heater is cool to the touch. A period of 30 to 40 minutes
should be sufficient to permit the heater to cool completely.
STEP 3: Check for the reason for overheating. Overheating is usually caused by
objects that impede free air circulation. Look for debris and other obstructions
near the heated air outlet and at the flue pipe top just outside of the dwelling.
3-9. Automatic Cleaning Cycle
The heater will automatically perform a self burner cleaning when the heater operates
continuously for five (5) hours. During the self cleaning cycle, the heater stops for two (2)
minutes and automatically restarts.

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Section 4: Maintenance
4-1. Introduction
The maintenance is divided into two classifications; routine maintenance, which is
required to keep the heater in good condition; and repairing and adjustment, which is
necessary to correct malfunctions.
4-2. Routine Maintenance
The maintenance schedule provided in Table below describes the tasks that must be
performed periodically for optimum heater performance.
At the time of the sale or installation, heater maintenance should be discussed with the
user; emphasize that a clean heater and proper fuel are the keys to optimum heater
operation and performance.
CAUTION: Be sure to unplug the heater from battery before checking of cleaning the
unit.
Allow the heater to cool completely before cleaning or maintaining.
TABLE
TASK 1: Check all fuel lines for leaks and loose connections.
Remarks: Fuel lines must be secure and free of leaks. Replace tubing if necessary.
TASK 2: Inspect exhaust lines for leaks or loose connections.
Remarks: All exhaust lines must be covered with insulation.
TASK 3: Check fuel strainer for water and/or other contamination. Make sure that the
fuel supply pipe is tightly connected to the unit and strainer.
Remarks: Replace a plugged strainer with a new one.
TASK 4: Inspect the fuel pipe for obstruction.
Remarks: The piping should be free of sharp bends or obstructions. Air locks can block
the fuel supply.
TASK 5: Inspect the burner ring, and the flame rod. (at least every year)
Remarks: Remove all carbon deposits.
NOTE: If any gaskets are torn when components are removed, the gasket
must be replaced.
TASK 6: Clean the heat chamber and the burner assembly. (at least every year)
Remarks: Vacuum all carbon deposits from the interior of the heat chamber and burner
air holes. Remove all carbon from the burner bottom. Use a small, stiff brush
or short piece of soft copper wire to clean any clogged air holes. Change the
burner mat if necessary.

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TASK 7: Clean the igniter
Remarks: Scrape any carbon deposits from igniter.
WARNING: Be careful when you remove igniter, it may be stuck. Excessive
force may crack the igniter.
TASK 8: Check air line and blower motor assembly. (at least every year)
Remarks: Replace the air line if it is worn or broken. Also, clean the exhaust fan if
necessary.
TASK 9: Check for carbon built-up on or inside fuel nozzle. (every year)
Remarks: Disconnect the copper fuel line from the fuel nozzle. Clean inside the nozzle
with the proper sized iron straight wire.
CAUTION: If any obstruction is felt, remove the fuel nozzle before proceeding.
4-3. Inspection of Exhaust/Air Lines
Verify that all air intake/exhaust pipes are free of leaks and that there are no loose
connections, as specified below.
(1) Inspection of Air Intake/Exhaust Pipe
A. Visually inspect both the air intake and exhaust pipes for obvious cracks, leaks or
loose connections. Black carbon deposits may be evidence of leakage.
B. Be sure that all pipes are installed tightly and securely, especially at the joints.
C. Turn the heater on.
D. Carefully apply a small amount of soapy water (with a paint brush) to the surface
areas of the air intake/exhaust pipes. Any leaks that may exist will be readily
identified by the appearance of bubbles.
(2) Return to Operating Condition
A. Push in the HEAT switch to “OFF”.
B. Dry all pipes with paper towels.
C. Repair any leaks that have been found (if necessary, replace the pipe or gasket).
4-4. Verification of Igniter Operation
Visually inspect igniter operation.
WARNING: Heater is operational during this inspection. Avoid direct contact with any
heated or electrical component.
(1) Prepare for Inspection; Remove cabinet B.

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(2) Visual Inspection
A. Push in the HEAT switch to “ON”.
B. Look downward through the peep window on the heat chamber. Verify that igniter
is glowing. If the igniter does not glow, something is wrong. Refer to
Troubleshooting in Section 6 of this service manual to solve the problem.
(3) Reassembly of Heater; Push in the HEAT switch to “OFF”and replace the cabinet B.
4-5. Fuel Contamination
Fuel contamination is often difficult to diagnose, even though it will adversely affect the
heater operation and performance. The best course of action to take when fuel
contamination is suspected is to examine all of the fuel line, beginning with the fuel
strainer. If the strainer is clogged, replace it with a new one.
WARNING: Before proceeding further, unplug the heater.
When it has been determined that water or some other contaminants have infiltrated the
fuel, the following procedure should be used.
STEP 1: Remove contamination
Drain the contaminants from tank or disconnect the fuel supply tube and clean
the contamination from the fuel tank. Refill with fresh and clean fuel.
STEP 2: Clean the heater
a. Replace the fuel strainer.
b. Using clean paper towels, thoroughly wipe the bottom of the burner, the
burner ring, the flame sensor (flame rod), and the heat chamber. Replace
the burner mat, if necessary.
STEP 3: Reinstall the cleaned components
a. Replace the components correctly and install new gaskets, if necessary.
b. Supply power to the heater.
Test-run the heater to see if the problem clears up, using new clean fuel.