Snugger SF2300 User manual

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AIR-HEATER FOR VEHICLES
Technical description
Installation instructions
Operating instructions
Maintenance Instructions

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Contents
P 01 Operating Principle and Use of SF2300 Air Heaters
P 02 Main parts of SF2300 Air Heaters
P 03 Installation Instructions and Regulations
P 04 Safety Instructions and Operation
P 05 Technical Data and Dimensions
P 06 Choosing Heater Location and Position
P 07 Installation of Heater Air System
P 08 Combustion Air System
P 09 Exhaust System
P 10 Fuel Supply
P 11 Operating Instructions
P 12 Description of Functions
P 13 Controls and Safety Device
P 14 Electrical System
P 15 Troubleshooting, Malfunctions and Maintenance
P 16 Installation Components Diagram SF2300
P 17 Heater Assembly Drawing SF2300

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Operating Principle and Use of SF2300Air Heaters
The SF2300 air heaters are designed to be used as auxiliary heaters for trucks, RVs, boats,
construction and farm equipment. The heaters will provide heat and keep a comfortable air
temperature for the operator (driver) cab, small RV, passenger vans, mini buses, boats, etc for a
fraction of the cost in comparison to engine idling. Automatic controls will keep the air
temperature in your comfort zone.
Compact design, low volume, easy maintenance, safety protection, auto self diagnosis, optional
timers, wireless remote control, low emissions and low operating cost makes the heaters ideal to
use in trucks, boats, farm and construction equipment.
Main parts of SF2300 Air Heaters
(1). Combustion chamber
(2). Blower motor
(3). Hot air blower wheel
(4). Control unit
(5). Combustion air blower
wheel
(6). Overheat/Flame sensor
(7). Heat exchanger
C: Combustion air
E: Exhaust
F: Fresh air intake
H: Hot air output

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◆Operation
The fuel pump delivers fuel to the heater atomizer. The glow pin ignites the fuel-air mixture.
Burning fuel heats up the heat exchanger. The heat is transferred into circulating air through
the heat exchanger, and then the warm air circulates through the truck cabin or sleeper berth
keeping it warm.
◆Use and Application
Widely used in: cars, commercial and industrial equipment, trucks, passenger vans, buses,
motor and sail boats, and houseboats. In addition, the heaters are used for heating RV’s, travel
trailers, recreational cabins.
Installation Instructions and Regulations
◆Heater Installation
Select the location to place the heater, most of the time the heater is installed on the floor or
side wall under the bed in the truck storage compartment or under the seat in passenger vans
in order for the heater exhaust fumes to be exhausted directly to the outside of the cabin or
passengers space, and the warm air can be easily distributed throughout the cabin.
The Heater shall be protected from excessive heat, exposure, and possible contamination from
fuel or oil. Keep heater exhaust away from electrical wires, fuel lines, water lines, and any
other heat sensitive and flammable materials. Provide sufficient ventilation. All precautions
must be taken when arranging the heater placement to minimize the risk of injury or damage
to property.
◆Fuel Supply
The fuel intake connections shall NOT be in the passenger compartment or operator (driver)
cabin. In vehicles where a separate fuel tank is used for the heater, the fuel tank lines and
intake connection must be clearly identified. A warning sign shall be permanently attached to
the intake connection or fuel tank indicating that the heater must be switched OFF before
refueling.
◆Exhaust System
The exhaust outlet must be arranged in a way that the exhaust fumes go directly to the outside
of the vehicle. Prevent penetration of exhaust fumes into the vehicle interior through the
ventilation system, warm air intakes, or open windows.
◆Combustion Air Intake
The heater combustion air shall NOT be taken from passenger compartment, cargo space or
operator (driver) cabin. The air intake shall be protected from possible water, debris, snow and
ice intake into combustion chamber, and cannot be blocked by any object at any time. Point
the air intake away from vehicle travel direction.

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◆Please Note:
Failure to comply with the regulations, safety instructions, repairs done by unauthorized
person, or use of aftermarket parts voids warranty and relieves manufacture, distributors,
dealers, and installation technicians from any and all liabilities.
·The installer is responsible for all damages to the property or person that arises from faulty
installation of the heater.
Safety Instructions and Operation
Disconnect vehicle battery power before commencing repair or performing heater maintenance.
Before beginning any work on the heater, switch the heater OFF and let all hot parts cool down.
The heater shall NOT be used in: poor ventilated rooms, garages, shops, multi-storage car park,
etc. Use heater only in open, well ventilated areas.
Use of aftermarket parts is strictly prohibited unless authorized by the manufacturer. Installation
and operation of the heater shall comply with statutory regulations, safety instructions and
specifications as stated in the installation and operating instructions.
Extreme precaution shall be taken when installing and maintaining electrical wiring, fuel supply,
combustion air and exhaust system.
Unauthorized persons are not allowed to do any repairs or maintenance.
Debris and any other remains shall be removed and cleaned before reinstalling the heater into
another vehicle.
The heater shall NOT be used in hazardous places such as but not limited to: fuel depots, carbon
storage, timber warehouse, granaries and other places where combustible or flammable vapor or
dust may be present.
Heater must be switched OFF during refueling. The heater shall be installed in a spacious
compartment. Fuel canisters, oil cans, spray cans, gas cartridges, fire extinguisher, cleaning rags,
clothing, papers, or any combustible or flammable materials shall NOT be stored or transported on
or next to the heater.
Defective or burned fuses shall be replaced only with same type and same rating fuses. In the
event of a fuel leak; turn OFF the heater immediately, disconnect and cap off fuel line. The leak is
to be repaired by a professional, authorized technician.
◆Please note:
DO NOT shut down the heater by disconnecting the power unless required to do so by an
emergency.

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WARNING
Carbon monoxide monitoring sensor with alarm shall be installed in all passenger
compartments, operator or driver cabin, and sleeper berth.
Technical data and specifications
Model
SF2300
Heating value
(±10%) Btu/hr (kW)
Super High Medium Low
7850 (2.3) 6485 (1.9) 4437 (1.3) 3072 (0.9)
Fuel
Consumption US. Gal/hr (l/h)
0.07 (0.28) 0.06 (0.24) 0.04 (0.15) 0.02 (0.1)
Fuel type
Diesel
Air flow (±10%) cfm 49 41 28 20
Electric power
consumption (watt)
(12 and 24 V)
34 23 13 9
Start-up (12 and 24 V) Watt ≤100 W
Rated voltage 12 and 24 Volt
Voltage lower limit About 10.5 Volt and 21 Volt time-voltage protection: 20sed
Voltage upper limit about16 Volt and 32 Volt time-voltage protection s: 20sed
Overheat protection (±10%)
(115
℃
) 239 F
Allowed ambient temperature
(
－
40 C ~ 76 C)
－
40 F ~ 168 F
Weight lb (kg) About. 6 lb (2.7kg)
◆Please note:
Listed technical data is subject to the tolerances of ±10 %.
◆Heater Dimensions
Overall dimensions

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Choosing Heater Location and Position
Most of the time the heater is installed on the floor under the bed in the truck storage compartment,
or under the seat in passenger vans or mini busses.
◆Tolerable swivel range
Depending on the installation conditions, swivel angles should be as shown below:
Note: The glow pin→shall face upward.
◆Please note:
In the heating mode, the heater can deviate from the shown normal or maximum installations
positions by up to +15° in all directions in order to accommodate the vehicle or boat
movement.
◆Mounting heater on the floor or wall using mounting plate
Fastening the heater on the vehicle floor or wall
If the mounting surface is not smooth and even use the mounting plate.
Cut hole in floor or wall if using mounting plate as shown on the drawing.
◆Mounting heater on the floor or wall without mounting plate
When installing the heater without the mounting plate, cut holes in floor or wall. The floor or
wall shall be smooth and even.

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Use sealant foam between mounting plate and wall or floor.
Installation heater air system (Example)
Item
Description
Item
Description
1
Safety grid
5
Flexible duct
2
Air intake lid
6
Adjustable warm air outlet 1
3 Air outlet lid 7 Air intake grill
4 Hose clamp
◆Please note:Safety instruction:

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Prevent possibility of sucking the engine or heater exhaust fumes into the heater.
Prevent the warm air to be directly sucked back into the cold air return.
Use only temperature-resistant hose (flex) for the hot air.
Install protective cover over the heater if there is possibility that the heater may by touched by
passenger (s) or operator when heater is using to prevent personal injury and also protect the
heater from possible damage from cargo or contact with flammable materials.
Install hot air duct in the way so it is protected from possible touching by humans and or heat
sensitive materials.
Install cold air return in the way so it will not suck the air from dirty or contaminated
environment.
Combustion air system
Install the tube of the combustion air intake in such a way that the air intake is protected from
sucking water, snow, ice, dust, hot air, exhaust fumes or any other debris into the combustion
chamber.
Inner hose diameter φ1”(25 mm) max. Length 55”(1.5m), depending on the installation
conditions.
Exhaust System
The flexible exhaust pipe inner diameter of φ15/16 ”(24mm) can be shortened to no less
than 8”(0.2m) from the heater to the silencer (muffler) but not longer than a total of 78” (2m)
including muffler; fasten the exhaust silencer (muffler) at suitable position to the vehicle
frame, route the flexible exhaust pipe from the heater to the exhaust silencer and fasten with
hose clamps. Use hose clamps to attach the exhaust flex pipe to the vehicle body.
◆Safety Instruction
Warning

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The entire exhaust system gets very hot during operation and immediately after the heater has
been working. Keep the exhaust system parts away from any flammable materials; wires,
hoses, fuel lines, carpets, plastics, brake lines, etc.
Maintain at least 1/2” air gap between the exhaust pipe and sheet metal walls in order to
prevent the heat transferring through the metal and damaging materials on the other side
of the wall. Use heat shields if necessary. Point the heater exhaust tail pipe slightly
downward, in open air, away from travel direction and at least 12” away from any
combustible or flammable materials. Tail pipe cannot protrude beyond the lateral limits of
the vehicle. Route the exhaust pipe in such a way so the exhaust fumes cannot be sucked
into the vehicle.
Do not perform any work on the exhaust system while the heater is working. Before
working on the exhaust system, first turn the OFF heater and wait until all parts have
cooled down completely, always wear safety gloves and eye protection.
Fuel Supply
The following safety instructions must be observed when mounting the fuel pump, routing fuel
lines and installing fuel tank pick-up tube.
Turn OFF vehicle engine and heater before working on the fuel supply or before refueling. Do not
use“naked” lights, open flames, do not smoke, do not inhale fuel vapors and avoid fuel contact
with skin. Work only in well ventilated area.
When installing fuel lines, use only a sharp knife to cut fuel hoses and pipes. Interfaces shall not
be crushed and must be free of burrs.
The fuel line from the pump to the heater should be installed at a continuous rise.
Fuel lines must be fastened to avoid damage and / or noise from vibrations.
Route the fuel lines in a way that they are protected from vehicle distortion, movement, etc. Never
route or fasten fuel lines to the heater or vehicle exhaust system. When the fuel line crosses a hot
element, always ensure there is sufficient clearance. If necessary, install heat deflection plates.

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Item Description Item Description
1-Fuel intake pipe 2 / 3 / 7 ·Fuel hose
6 ·Fuel pump 5 ·Fuel line connecting hose
4 ·Fuel filter
◆Safety Instructions for fuel lines and fuel tanks in passenger compartment
In a passenger buses, vans or any other passengers vehicle the fuel lines and fuel tanks shall
NOT be routed through the passenger compartment, operator or driver’s cab
Fuel tanks in passenger vehicles must be positioned in such a way that the exits are NOT in
direct danger from a possible fire.
◆Fuel supply for diesel heater using T connector
You may use T connector to tap into existing fuel line as long as the T is installed before
engine fuel pump.
◆T fitting Setting Angle
Use the installation positions shown in the diagram when inserting a T fitting.
1 Direction of flow from the fuel tank 2 Direction of flow to vehicle engine
◆Max. suction and pressure height
Max. height from fuel tank to heater －a= 12’(3.6m)
Max. suction height from bottom of tank －b= 3.9’(1.2m)
Max. heater height －c = 10’(3.0m)
1 －Connection to heater
2 －Max fuel level
3 －Min. fuel level

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◆Mounting of fuel intake system Install method
Drill 31/32” (24mm) hole in appropriate location in top of fuel tank, as shown figure 1:
Mount the fuel intake system and fuel pump, as shown figure 2, 3
◆Please note:
When drilling into the fuel tank, take precautions to prevent possible sparks from electric
tools (ground all tools).
Prevent shavings and any other debris to fall into the fuel tank.

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Operating Instructions
Before starting the heater, perform a safety check: all components must be firmly fastened, check
for fuel leaks. Bleed fuel line and prime fuel pump.
To start the heater; turn the control knob to “high”(turn the knob clockwise), push heat button, the
blower motor will start running. After about 60 sec. the fuel pump will start pumping the fuel. If
the fuel is not ignited in about 90 sec. (possible air in fuel line) the igniter will shut down for about
1 min. and then it will start the process again. The process will repeat until there is no more air in
fuel line.
Heater at high altitudes:
1. Heating at altitudes below 5,000 ft (1,500 m), -unlimited heating possible.
2. Using heater at altitudes higher than 5,000 ft (1,500 m) requires installing an altitude
pressure sensor.
Description of functions
◆Operation
When the heater is turned ON, the control lamp (Red) comes ON. The combustion air blower
starts running, the glow pin will starts heating up, and fuel pump starts pumping fuel. Once
the flame is stable, glow pin will turn OFF.
◆Heating mode
Once the air reaches the desirable temperature fuel pump will turn OFF, the combustion fan
and air fan will keep operating on the low speed, the heat light will stay ON. The heater will
restart after the air temperature drop below setting point. After the heater is turned OFF the air
fan and combustion air fan will operate for approximately 2 mins on the low speed in order to
evacuate exhaust fumes and cool down the combustion chamber.
Controls and Safety Device
If the heater does not ignite within 90 seconds after starting the fuel pump, the start process
repeats several times. After several unsuccessful starting attempts the controller will lock the
system in order to prevent fuel flooding the chamber. You can restart the process by switching the
heater OFF and then ON again.
If the flame goes off during operation, the heater will restart by itself. If the heater does not ignite
after several attempts, the heater will lock and it will need to be turned OFF and ON manually.
In the case of overheating (for example, debris clogging the cold air intake, poorly vented warm

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air), the overheating sensor is triggered, the fuel supply is interrupted and the heater turns OFF.
Once the overheating has been eliminated, the heater can be restarted manually by turning OFF
and ON again. If the heater has been switched OFF and ON too many times in short period of time,
the controller will lock, wait for about 15 mins and turn the heater ON again.
If the lower or upper voltage limit is reached, the heater will turn OFF.
The heater does not start when the glow pin is defective or when the fuel pump power is
interrupted.
The fan speed is continuously monitored. If the fan motor does not start or if the speed deviates by
more than 40%, the heater will turn OFF after 60 sec.
The controller can be enabled again and it will flash fault code:
Use chart below to read the fault code list.
Do not switch the heater OFF and ON again more than twice.
◆Please note:·Emergency shut down.
In event of an emergency, shut down the heater as follows:
◆·Try to turn the heater OFF with the control panel.
◆·Pull the fuse out.
◆·Disconnect battery power.
Electrical systems
Safety Instruction for wiring the heater
The Heater shall be connected to the power according to the EMC requirements. See
instruction below;
1. Ensure that the electric cable’s insulation is not damaged. Avoid: chafing, kinking,
jamming or exposure to heat.
2. Seal all unused connector chambers with filler plugs to ensure no dirt enters in and stays
water-proof.
3. All electrical connection shall be free of corrosion and firmly connected.
4. Lubricate all outside connections with contact grease.
◆Wiring of the Heater

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◆Annex list
Wire color Function Wire color Function
Red DC 12V/24V (＋) Brown line of communication A
Black GND (－) Orange line of communication B
Yellow Starting line Amethyst Fuel pump line (＋)
◆Control module
Troubleshooting, Malfunctions and Maintenance
◆Malfunction checklist
Heater does not start after being turned on; switch the heater OFF and ON again. If the heater
still does not start, check the following:
1. ·is there fuel in the tank?
2. ·are fuses ok?
3. ·are electrical cables, all connections, etc OK?
4. ·is anything clogging the combustion air supply or exhaust system?

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5. ·check the air fan if it is spinning freely
6. ·does the control panel flash the fault code?
◆Troubleshooting diagnosis chart
Please record the number of closed when the lamp is flashing, while the heater function
failure. Then check the list 4.1 and shoot trouble.

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List 4.1
Code flashing
times Description Solution
1 Time The power supply voltage too high Check the voltage, possible alternator drive belt
too loose, check charging system
2 Times The power supply voltage too low Check the voltage, charge battery, check charging
system
3 Times The burner temperature sensor
malfunction Check the temperature sensor connection and
position whether it is correct
Check the temperature sensor wires for possible
damage or short
4 Times Inlet air temperature sensor is fault
5 Times Outlet air temperature sensor
malfunction
6 Times Glow pin malfunction
Check the voltage between glow pin terminals it
should read 12 or 24 V
Check for broken wires and loose connection,
shorting out wires
Remove and check the glow pin for any visible
damage; replace glow pin if damaged
7Times Fuel pump malfunction
Check the voltage at fuel pump
Check wires for damage and connections and short
circuit at fuel pump
Check fuel pump for any damage
8 Times Blower malfunction
Check blower wires for damage and proper
connections
Check blower for any visible damage
10 Times Ignite fail or flame extinguish
protection
Check whether there fuel in tank
Check all fuel connections
Check if fuel pump is working
Check if the glow pin is working normally
Check if the air inlet / exhaust is blocked
11 Times Burner overheating protection Check the fuel pump pressure
Defective fuel injector
12 Times Outlet warm air temperature
overheating protection
Check the return inlet air and warm outlet air for
blockage
13 Times
Flame extinguished or burner
overheating forbids the system
operation
Disconnection power and re-connection again
14 Times Communication fault Check all wire connection
To reset the system: press “OFF” button→waiting for 15 minutes, it should clear the fault codes,
turn ON the system. If the system does not clear the code, disconnect battery power, wait few
minutes, hook up the battery power and turn the system ON.

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◆Maintenance Instructions
1. Switch the heater ON at least once a month for about 10 minutes, even if there is no need
for heat.
2. Check the opening of the combustion air supply and the exhaust system after longer
standstill periods; clean if necessary.
3. Before the heating period starts the heater should undergo a trial run. If persistent extreme
smoke, unusual burning noises or unburned fuels smell develop or if electric / electronic
parts heats up, the heater shall be switched off immediately. Remove fuse or disconnect
battery power.
4. At least once a year have the heater checked by authorized, trained service technician.
Remove glow pin and atomizer screen; clean the screen and the atomizer chamber with
wire brush, if notice that there is excessive carbon build up the entire combustion
chamber shall be cleaned out.
◆Please note
The warranty claims will become void if the heater is repaired or serviced by an unauthorized
person .
◆Explain
Instruction: one time flashing is point to the light on to light out the illustrations show forth time
flashing, it mean there are sensor abnormal from the above form show like that.

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Installation Components Diagram SF2300

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Components list of the air-heater
Item # Part NO Description QTY
1·SF2300 ·Heater 1
2·SF2-000206 ·Safety screen 1
3·SF2-000600 ·Heater Harness 1
4·SF2-000411 ·Cable ties 30
5
·SF2-000405 ·Fuel pipe,φ4 x 1 mm
8m
6
·SF2-000408 ·Air inlet pipeφ25 mm
1
7·SF2-000409 ·Exhaust pipeφ24 mm 1
8·SF2-000409 ·Exhaust silencer 1
9·SS4-015 ·End sleeve, Exhaust pipe 1
10 ·SF2-000417 ·Pipe-clamp #2 1
11 ·SF2-01 ·Fuel pump 1
12 ·SF2-000602 ·Fuse 5A 1
13 ·SS4-032 ·End sleeve, Air inlet hose 1
14 ·SF2-000406 ·Fuel pipe φ5 x 3 mm 1m
15
·SS4-033 ·Fuel pickup assembly
1
16
·SF2-000610 ·Mini control panel
1
17 ·SF2-000601 ·Fuse 24V/15A (12V/20A) 1
18 ·SF2-000413 ·Hose clamp #3 4
19 ·SF2-000410 ·Warm air hose φ60 mm 1
20 ·SF2-000240 ·Outflow 1 1
21 ·SF2-000220 ·Air intake 1
HeaterAssembly Drawing SF2300