Failure to comply with the precautions and instructions
provided with this heater, can result in death, serious
bodily injury and property loss or damage from hazards
of fire, explosion, burn, asphyxiation, carbon monoxide
poisoning, and/or electrical shock.
Only persons who can understand and follow the
instructions should use or service this heater.
If you need assistance or heater information such as
an instruction manual, labels, etc. Contact the
manufacturer.
WARNING
Fire, burn, inhalation, and explosion hazard. Keep solid
combustibles, such as building materials, paper or
cardboard, a safe distance away from the heater as
recommended by the instructions. Never use the heater
in spaces which do or may contain volatile or airborne
combustibles, or products such as gasoline, solvents,
paint thinner, dust particles or unknown chemicals.
WARNING
Not for home or recreational vehicle use
Page 2 S1505B Manual 974-9308 Rev. 4.32; Aug 29 2014
READ THIS
WARNING
FIRST!
The heater is designed and approved for use as a construction
heater under ANSI Z83.7-2000. The primary purpose of construction heaters is to provide temporary heating of buildings
under construction, alteration, or repair and to provide temporary emergency heat. Properly used the heater provides safe
economical heating. Products of combustion are vented into
the area being heated.
The heater is not designed as an Unvented Gas Fired Room
Heater under ANSI-Z21.11.2 and should not be used in the
home.
ANSI A119.2(NFPA 501C)-1987 Recreational Vehicle Standard prohibits the installation or storage of LP-Gas containers
even temporarily inside any recreational vehicle. The standard
also prohibits the use of Unvented Heaters in such vehicles.
NFPA-58 1989 STANDARD FOR THE STORAGE
AND
HANDLING OF LIQUEFIED PETROLEUM GASES
Use of the heater must be in accordance with this Standard and
in compliance with all governing state and local codes. Storage
and handling of propane gas and propane cylinders must be in
accordance with NFPA 58 and all local governing codes.
We cannot anticipate every use which may be made for our
heaters. CHECK WITH YOUR LOCAL FIRE SAFETY AUTHORITY IF YOU HAVE QUESTIONS ABOUT LOCAL REGULATIONS.
Other standards govern the use of fuel gases and heat producing products in specific applications. Your local authority can
advise you about these.
S1505B Manual 974-9308 Rev. 4.32; Aug 29 2014 Page 3
S1505B
CONSTRUCTION HEATER
FOR YOUR SAFETY
DO NOT USE THIS HEATER IN A SPACE WHERE
GASOLINE OR OTHER LIQUIDS HAVING
FLAMMABLE VAPOURS ARE STORED OR USED.
Contents:
Page
Specifications5
Installation6
Installation Using a Propane Supply Cylinder7
Installation for Natural Gas Applications7
Operating Instructions8
Common Installation and Operational Problems9
Safety Controls9
Safety Features10
On-Site Hazards10
Preventative Maintenance11
Troubleshooting Tables12
Replacement Parts20
Wiring Diagrams22
Two Stage Thermostat Wiring Diagram24
LPG - Propane Fuel Vaporization Rate25
Maximum BTU Content (Propane)25
Pressure & Flow Equivalents25
Page 4 S1505B Manual 974-9308 Rev. 4.32; Aug 29 2014
Specifications
AGA certified to ANSI Z83.7-2000 Construction Heater
Gases:Natural or Propane
Capacity:1,500,000 Btu/h maximum
850,000 Btu/h minimum
Orifice Size:41 DMS (X46)
Blower:7,000 cfm
Electrical Rating:115 volts, 60 Hz, 9.4 amps, Single Phase
Min. Temperature Rating:Minus 40 degrees F
Gas Supply:
Inlet PressureManifold Pressure
Max W.C.Min W.C.Max W.C. Min.W.C.
Propane14"9"2.7"0.75"
Natural14"9"7.2"2.0"
(Minimum inlet pressure is for purpose of input adjustment)
S1505B Manual 974-9308 Rev. 4.32; Aug 29 2014 Page 5
Installation
The Sure Flame Model S1505B is a direct fired gas heater intended to be
used primarily for the temporary heating of buildings under construction,
alteration, or repair. Since all the products of combustion are released into
the area being heated, it is imperative that adequate ventilation is provided.
The flow of supply air and combustion gases must not be obstructed in any
way. Do not use the heater with ductwork as this will restrict the flow of supply
air.
1Install the heater in a horizontal position at least 6 ft. (1.83 m) from any
LP-gas container, and allow the following clearances from any combustible materials:
Front Outlet:20 feetSides:2 feet
Intake:2 feetTop:4 feet
Front Outlet must not be directed at any LP-gas container within 20 feet.
Also make sure that no flammable vapours are present in the space
where the heater is being used.
2When connecting the heater to a natural gas or propane supply line
ensure that the pressure at the heater inlet is within the specified range.
Please refer to Propane and Natural Gas Installation sections in this
manual. Excessive pressure (over 1/2 psig) will damage the controls
and void the warranty.
3Visually inspect the hose assembly and ensure that it is protected from
traffic, building materials, and contact with hot surfaces. If it is evident
that there is excessive abrasion or wear, or the hose is cut, it must be
replaced.
4After installation, check the hose assembly for gas leaks by applying a
water and soap solution to each connection.
5Connect the heater to an adequate 115 volt electrical supply and in
compliance with the National Electrical Code, ANSI/NFPA 70. For
protection against shock hazard the supply cord should be plugged
directly into a properly grounded three-prong receptacle.
6In all applications install the heater in such a manner that it is not directly
exposed to water, spray, rain and/or dripping water.
Page 6 S1505B Manual 974-9308 Rev. 4.32; Aug 29 2014
Installation Using A
Propane Supply Cylinder
1When installing the heater for use with propane gas, set the gas selector
valve to “Propane” and lock in position.
2The supply container MUST be equipped with an LP Gas Regulator that
complies with ANSI/UL 144 Standard for Pressure Regulating Valves for
LP-Gas. Another regulator must be installed in the heater to reduce the
pressure from this regulator down to a maximum inlet pressure of 1/2 psi.
3Arrange the cylinder supply system to provide for vapour withdrawal from
the operating cylinder. Supplying liquid propane to the heater is
dangerous and will damage the components.
4Ensure that for the surrounding temperature the size and capacity of the
propane supply cylinder is adequate to provide the rated Btu/h input to
the heater.
5Turn off the propane supply valve at the cylinder when the heater is not
in use.
6The installation must conform with all local codes, or in the absence of
local codes, with the Standard for the Storage and Handling of LiquediedPetroleum Gases, ANSI/NFPA 58.
7When the heater is to be stored indoors, the propane cylinder(s) must be
disconnected from the heater and the propane cylinder(s) removed from
the heater and stored in accordance with the National Standard for the
Storage and Handling of Liquedied Petroleum Gases, ANSI/NFPA 58.
Installation For
Natural Gas Applications
1When installing the heater for use with natural gas, set the GAS
SELECTOR VALVE to the ”Natural” position.
2A regulator must be installed on the heater to ensure that the pressure
to the heater does not exceed 1/2 psi inlet pressure.
3The installation of this heater to a natural gas supply must conform with
all applicable local codes or, in the absence of local codes, with the
National Fuel Gas Code ANSI Z223.1/NFPA 54.
S1505B Manual 974-9308 Rev. 4.32; Aug 29 2014 Page 7
Operating Instructions
1.Set GAS SELECTOR VALVE to gas being used. The conversion shall
be done by the owner or lessor of the equipment.
Warning: When using propane gas, the GAS SELECTOR VALVE must
be locked in position.
2.Ensure FIRING VALVE is in the “ON” position.
3.Connect power cord to a 115 volt supply.
4.Open gas supply.
5.Set thermostat to the desired temperature.
6.Push START button. After a short delay, the heater will start.
Note: Heater will cycle between high flame, low flame, and off as
required.
7.To stop: push STOP button. If heater is to remain off, disconnect power,
and close gas supply.
The appliance area should be kept clear and free from combustible materials, gasoline, and other flammable vapours and liquids.
Ensure that the flow of supply air and combustion gases is not obstructed.
The installation and operation of the heater shall comply with the code
requirements specified by the authorities having jurisdiction.
General criteria for the use of construction heaters may be found in the
applicable sections of American National Standard A10.10-1987, Safety
Requirements for Temporary and Portable Space Heating Devices and
Equipment Used in the Construction Industry.
THE INSTALLATION AND MAINTENANCE OF THE
HEATER MUST BE ACCOMPLISHED BY A QUALIFIED
SERVICE PERSON.
Page 8 S1505B Manual 974-9308 Rev. 4.32; Aug 29 2014
Common Installation And
Operational Problems
1LOW VOLTAGE
This is one of the most common problems and is usually the result of the
supply cord having too small of a wire gauge for its length. Low voltage
results in the motor overheating, burnt relay contacts, or a relay that will
not make contact.
2SUPPLY LINE TOO SMALL
3INSUFFICIENT VAPORIZATION AT SUPPLY
Normally caused by too small size of supply tank.
4IMPROPER GAS SUPPLY PRESSURE
Usually a result of supply pressure being too high because of improper
or lack of regulation.
5DIRTY GAS SUPPLY
Dirty gas can cause strainers to plug or form a build-up in the burner
orifice.
6LACK OF PREVENTATIVE MAINTENANCE
Heaters must be cleaned as required, especially when used in a dirty
environment.
7IMPROPER SUPPLY OF FRESH AIR
It is normally recommended that the intake air of the heater be taken from
outside the enclosed area. This provides a slight pressurization and
prevents any problems associated with recirculation.
Safety Controls
Servicing of Sure Flame Construction Heaters normally involves one of
several built-in safety features. The Model S1505B incorporates devices to
detect the following:
1 LOSS OF FLAMEGas supply is shut off if flame is lost to
prevent raw gas from leaving the heater.
2 OVERHEATING(a) Thermal overload protection in the mo-
tor.
(b) High temperature limit switch in the
combustion chamber.
3 LOSS OF POWERTotal shutdown with manual reset required.
Any one of the safety devices will create a
loss of power situation.
4 BLOCKED AIR SUPPLYA switch detects the differential pressure in
the combustion chamber and shuts down
when insufficient .
5 LOW INLET PRESSUREA pressure switch monitors the gas inlet and
closes the safety shut-off valve if pressure
drops below the preset limit.
S1505B Manual 974-9308 Rev. 4.32; Aug 29 2014 Page 9
Safety Features:
1LOCKING POSITION FOR LPG ON GAS SELECTOR LEVER
Units used with LPG while the gas selector valve is positioned for Natural
Gas will produce significantly more heat than the rated Btu/h. This is
definitely a safety hazard.
2LOW SKIN TEMPERATURE
Sure Flame Heaters are designed to have a low skin temperature. This
provides added safety in the workplace.
3DURABLE CONSTRUCTION
The Model S1505B uses a stainless steel burner for long life and
consistent performance.
In order to maintain the highly efficient combustion of the Sure Flame
Heater, the combustion chamber must remain as manufactured. Any
change or distortion could alter the fuel/air mixture and create hazardous
gases.
On-Site Hazards
1SHORTING OUT OF DEFECTIVE COMPONENTS
This is a very common problem which saves short term expense at the
risk of a large future cost. Any heaters found in this condition should be
removed immediately.
2IMPROPER ENCLOSURES
When heaters are installed partially to the outside for fresh air intake,
strict adherence must be made to the minimum clearance to combustibles
given on the instruction plate. Wood framing around a heater is a hazard
and should not be used.
3SUPPLYING LIQUID PROPANE TO HEATER
This problem has occurred from time to time. To minimize the damage,
shut off the gas supply and let the heater run until all of the liquid in the
lines has been burnt.
Page 10 S1505B Manual 974-9308 Rev. 4.32; Aug 29 2014
Preventive Maintenance
Sure Flame Construction Heaters are built to withstand the rigours of
operating on construction sites, mining applications, and a multitude of other
locations where heaters are used. To maintain the reliable performance it
is necessary to perform regular maintenance.
AVISUAL CHECKS
The following items should be checked for excessive wear or damage:
1)Wheels
2)Cords and Connectors
3)Wiring and Conduit
4)Heater Shell (including heat shield) and Control Box
BBURNER
Flame Rod and Insulator - Clean with soap and water or solvent on a
routine basis. Any build up on burner should
also be removed at this time.
Ground Wire -Ensure that the ground wire is secured to
the burner. This is necessary for the flame
detection system to operate.
Spark Plug -Clean with solvent and check spark gap.
CFLAME SAFEGUARD CONTROL
The Fenwall Control can be cleaned using compressed air or alcohol. Do
not use any other liquid or aerosol spray cleaners.
In areas of high humidity, the control should be removed and placed in
a dry atmosphere when the heater is expected to be out of service for an
extended time.
It is recommended that units purchased as spares be rotated periodically, so that each unit will be placed in operation at least once every 90
days.
DMOTOR - Motors equipped with oil cups should require only a few drops
of clean, light machine oil every year. Motors not equipped with oil cups
are fitted with sealed bearings and no oiling is required.
EFAN - Check for dust or dirt build up on fan blades. Check the tightness
of the set screw and run the heater to check for fan vibration.
S1505B Manual 974-9308 Rev. 4.32; Aug 29 2014 Page 11
Troubleshooting
The troubleshooting section has been divided in to six tables. Choose
the appropriate table from the list below:
Chart A – Heater does not start, fan does not start
Chart B – Heater does not start, fan starts, no spark, no flame
Chart C – Heater does not start, fan starts, spark, no flame
Chart D – Heater starts, flame lights but goes out after a few
seconds
Chart E – Heater starts, but fails during operation
Chart F – Other problems
Page 12 S1505B Manual 974-9308 Rev. 4.32; Aug 29 2014
LED
Flame Control
Indicators Outside Control Box Indicators Inside Control Box
L12
L8
L7
L6
L2
2 Light
Thermostat Stage
1 Light
Thermostat Stage
Light
Thermostat Power
Red Stop Switch
Green Start Switch
off off off off on off off off * Off
off off off off off off off off off off off
off off off off off on off off off off off
on/
off
on off off off off on off off off off Off
on off - - - on off off off off off
on off on - - on off off off off off
on off on on - on off off off off off
on on on on - on off off off off *
on on on on - on on off off off *
on on on on - on on off off off *
on on on on - on * * off off off
on on on - - on off off off off *
Chart A – Heater does not start, fan does not start
Symptom Possible Causes
S1505B Manual 974-9308 Rev. 4.32; Aug 29 2014 Page 13
No electrical supply
Stop switch fails open
Start switch fails open
Fuse failure
Green start light does not
come on when start switch is
pressed.
Green start light comes on
Reset switch fails open
when pressed, but goes off
when released. L12 flashes
when start switch released.
Green start light is on, but red
Thermostat stage 1 fails open
Flame control failure – Power in
stop light remains off during
attempts to start.
Flame control failure – Motor out
Motor relay fails open
Motor failure
Low Voltage (long extension cord or too
Flame control failure – Thermostat in
Green start light is on, red stop
many items on circuit). Motor relay may
light comes on during attempts
to start
chatter.
Air switch fails closed
LED
Flame Control
Indicators Outside Control Box Indicators Inside Control Box
L12
L8
L7
L6
L2
2 Light
Thermostat Stage
1 Light
Thermostat Stage
Light
Thermostat Power
Red Stop Switch
Green Start Switch
on on on on - on on off off off *
on on on on - on on off off off *
on on on on - on on off off off *
off ***
off
on on on on - on on on off off *
on on on on - on on on on/
Chart B – Heater does not start, fan starts, no spark, no flame
Symptom Possible Causes
Page 14 S1505B Manual 974-9308 Rev. 4.32; Aug 29 2014
Motor wired incorrectly
Air tubes set in wrong position
Air switch fails open
Air switch set to too high a pressure
Air blowing through heater in
reverse.
No gas odor at heater outlet.
L7 light is off. Voltage
between N2 and L15 is 120V
Air tubes plugged
Strainer plugged or dirty
Gas pressure switch fails open
Too small of a hose, too long of a hose,
blocked hose
Too low of inlet pressure
Second stage regulator set too low
Propane tank too small to vapourize fast
during attempt to start.
No gas odor at heater outlet.
L7 light is off. Voltage
between N2 and L15 is 0V
during attempt to start.
Upstream regulators installed backwards
Flame control failure – Air in
enough, tank freezes
No gas odor at heater outlet.
Spark plug wire damaged
Flame control failure – spark out
Spark plug fails
Flame rod and spark plug wires reversed
L7 light is on.
Gas odor at heater outlet. L7
light on. L8 light on, then off.
LED
Flame Control
Indicators Outside Control Box Indicators Inside Control Box
L12
L8
L7
L6
L2
2 Light
Thermostat Stage
1 Light
Thermostat Stage
Light
Thermostat Power
Red Stop Switch
Green Start Switch
on on on on - on on on off off ***
on on on on - on on on off off ***
off ***
off
on on on on - on on on on/
off ***
off
on on on on - on on on on/
Chart C – Heater does not start, fan starts, spark, no flame
Symptom Possible Causes
S1505B Manual 974-9308 Rev. 4.32; Aug 29 2014 Page 15
Limit switch fails open
No gas odor at heater outlet.
Flame control failure
L8 light is off. Voltage
between N2 and L17 is 120V
during attempt to start.
No gas odor at heater outlet.
L8 light is off. Voltage
between V1 and V2 on flame
controller is 0V during attempt
Too high of inlet pressure. Second stage
regulator set too high. (This may cause the
Solenoid valve fails closed
L8 light is on, then off.
2-stage regulator to be damaged
Gas pressure switch failed closed and inlet
Gas odor at heater outlet. L8
Manual valve closed
to start.
No gas odor at heater outlet.
pressure low
2-stage regulator installed backwards
Burner orifices plugged or dirty
Spark plug gap too large (weak spark) or
too small. Gap should be set to 1/8 inch.
light on, then off.
Low flame regulator setting too low
LED
Flame Control
Indicators Outside Control Box Indicators Inside Control Box
off ***
L12
off
L8
L7
L6
L2
2 Light
Thermostat Stage
1 Light
Thermostat Stage
Light
Thermostat Power
Red Stop Switch
Green Start Switch
on on on on - on on on on/
off ***
off
on on on on - on on on on/
Chart D – Heater starts, flame lights but goes out after a few seconds
Symptom Possible Causes
Page 16 S1505B Manual 974-9308 Rev. 4.32; Aug 29 2014
Flame control failure – Flame sensing
Connect DC current meter with
microampere range to
terminals FC+ and FC- of the
flame controller. Start heater.
Check reading once flame is
established. Reading is 1.0
microamperes or higher
Flame rod dirty, cracked, or otherwise
defective.
Flame rod wire loose or damaged
Reading from above is less
than 1.0 microamperes.
Burner not grounded
LED
Flame Control
Indicators Outside Control Box Indicators Inside Control Box
L12
off off ***
L8
on/
off
L7
off
L6
L2
2 Light
Thermostat Stage
1 Light
Thermostat Stage
Light
Thermostat Power
on on - on on/
Red Stop Switch
off
Green Start Switch
on on/
on on on on - on on off off off *
off off ***
on/
off
off
on on on on on on on/
off off ***
on/
on on on on on on on/
off
off
Chart E – Heater starts, but fails during operation
Symptom Possible Causes
S1505B Manual 974-9308 Rev. 4.32; Aug 29 2014 Page 17
Low Voltage (long extension cord or too
many items on circuit)
Propane tank too small to vapourize fast
Normal flame length prior to
failure. Three flashes on flame
control LED.
Smaller than normal flame
Strainer plugged or dirty
Limit switch failure – too sensitive
enough, tank freezes
prior to failure. Single flash on
flame control LED.
Normal flame length prior to
failure. Three flashes on flame
control LED. Immediately after
failure, voltage between N2
and L17 is 120V, between N2
Changeover valve set to natural gas when
and L16 is 0V.
Longer than normal flame
connected to propane.
before failure, possibly
High flame regulator setting too high
Connected to liquid propane
Too high of inlet pressure
Second stage regulator set too high
shooting outside of heater
body. Three flashes on flame
control LED. Immediately after
failure, voltage between N2
and L17 is 120V, between N2
and L16 is 0V.
LED
Flame Control
Indicators Outside Control Box Indicators Inside Control Box
L12
L8
L7
L6
L2
2 Light
Thermostat Stage
1 Light
Thermostat Stage
Light
Thermostat Power
Red Stop Switch
Green Start Switch
on off on on - on on on on off off
off off off off off on off off off off off
on off on - - on - - - - -
on off on on - on on on on off off
on off on on on on on on on off off
on off on on - on on on on off off
on off on - - on on on on off off
on off on on - on on on on off off
- - - - - - - - - - -
- - - - - - - - - - -
Chart F – Other Problems
Symptom Possible Causes
Page 18 S1505B Manual 974-9308 Rev. 4.32; Aug 29 2014
Damaged or unbalanced fan blade
Motor relay fails closed
Excessive vibration or noisy
operation.
Fan motor starts immediately
Start switch fails closed
when heater is plugged in,
even if thermostat is not calling
for heat
Heater will start as soon as it is
Low flame regulator setting too low
High flame regulator setting too low
Changeover valve set to propane when
connected to natural gas
plugged in. Stop button will
reset the heater.
Flame length shorter than
normal
Normal operation except flame
length shorter than normal
Small flame, otherwise
functions normally.
Thermostat stage 2 fails open
Low flame regulator setting too high
Solenoid valve fails open
Solenoid valve leaks
Heater will never go to high
flame.
Normal operation, but low
flame longer than normal.
Gas will flow to burner
immediately when supply to
heater is opened
Gas will flow to burner
immediately when supply to
heater is opened
- - - - - - - - - - -
on off on on - on on on on off off
on off on - - on on on on off off
on off on - - on on on on off off
on off on on - on on on on off off
on off on on - on on on on off off
*
off
off off
on/
off/
on
off/
on
on off on on - on on on on off off
on off on on - on on on/
on off on on - on on on on off off
on off on on - on on on on off off
Solenoid valve installed backwards
Gas will flow to burner
Thermostat stage 1 fails closed
immediately when supply to
heater is opened
Heater lights but uneven flame. Burner orifices plugged or dirty
Heater will always stay on
(either high or low) regardless
S1505B Manual 974-9308 Rev. 4.32; Aug 29 2014 Page 19
Thermostat stage 2 fails closed
Reset switch fails closed
of ambient temperature
Heater will switch between off
and high, but never low flame
Heater will function normally,
Flame control failure – NC light out
but if it shuts down, it will not
start up again without pressing
the stop switch
Heater will function normally,
but red light does not come on
during startup sequence
Stop switch fails closed
Air switch set to too high a pressure
Heater will start normally but
will not stop when the stop
switch is pressed
During operation, flame goes
out for a few seconds, then
relights. Stage 1 thermostat
Air switch set to too low a pressure
light remains on during this
time.
Heater will continue operating
when the air flow is obstructed
Limit switch fails closed
with longer than normal
flames. Limit switch may
cause heater to shut down.
Heater will start normally, but
will not shut down in an
overheat situation
A8
C3
C4
C5
C6
C8
C7
C9
C10
B9
B3
B2
C1
C11
C12
C20
C13
C14
C15
C16
C19
B1
D16
D15
C17
C18
A10
A11
D19
D18
D17
D14
D2
D21
D22
D20
D10
D11
D13
D12
D7
D1
D3
D4
D5
D6
D8
D9
A7
A6
A5
A4
A3
A2
A1
B8
D24
B10
B7
D23
A9
B4
B6
B5
Replacement Parts
Page 20 S1505B Manual 974-9308 Rev. 4.32; Aug 29 2014
D3S1500-105DIN Mounting Rail
A1S1505-56Heater Body (Includes A 10 & A11)C13 S1500-710Adjusted A ir Sw itch
A22446Limit Sw itch, 180°F C14 1707Silico ne Tubin g
C12 5509Snap Bushing, 1/2"D24 WR7BAY- 66 Flame Rod Wire
S1505B Manual 974-9308 Rev. 4.32; Aug 29 2014 Page 21
S1505B Connection Wiring Diagram
START
BUTTON
X1
X2
4
32
1
BLK
BLK
BLK
STOP
BUTTON
X1
X2
2
1
BLK
BLK
WHT
BLK
BLK
BLK
WHT
WHT
BLK -14Ga
WHT -14Ga
POWER
THERMOSTAT
RECEPTACLE
BLK
684 2
LOGIC
RELAY
10
WHT
BLK
684 2
RELAY
MOTOR
10
WHT
G0G0
G1G1G1G1
N2L2L2N2
WHT
BLK
CONTROL BOX
14/3 SJTW
BLK -14Ga
WHT -14Ga
GRN -14Ga
GRN
BLK
WHT
MOTOR
WHT
N3L3L3N3
WHT GTF -16Ga (HT)
N4L4L4N4
N5L5L5N5
MOTOR
PRL
BLK
BLK
BLU
YLW
ORG
WHT
BLK
GAS
N6L6L6N6
RED
GRN
AIR
N7L7L7N7
N8L8L8N8
N9L9L9N9
N10L10L10N10
ORG
WHT
FLAME ROD
VALVE
SOLENOID
Note: All wires 18 Ga STR TEW 600V unless otherwise specified.
BURNER
PLUG
SPARK
BLK GTF -16Ga (HT)
NC
V1
PSW
L2
V2
L1
IND
TH
GRN
S1
FLAME CONTROLLER
FENWAL 35-71
Page 22 S1505B Manual 974-9308 Rev. 4.32; Aug 29 2014
BRN
WTH
RED
BLK
FUSE
L11L11L11L11
L12L12
L13L13 L13
L14L14 L14
L15L15
BLK
L16L16
L17L17
P
SWITCH
RED GTF -16Ga (HT)
RED GTF -16Ga (HT)
BLK
ORG
RED
BLACK
BLU
YEL
YEL
COM
1
NC
AIR
2
NO
COM
PV
MV
STG 1
PV
STG 2
MV
REGULATOR
BLK ICS -14Ga
SWITCH
WRB
PRESSURE
LIMIT
SWITCH
Rev 2.21 From S/N: 3960
Ladder Wiring Diagram
IND
TH
PSW
V1
L1
V2
L2
NC
S1
GND
HV
Power Light (L2)
M
Thermostat Coil
Motor Relay Coil
Motor Light (L6)
Gas Pressure
Switch (NO )
Thermostat
1st Stage
Contact (NO)
Heater Limit
Switch (NC)
Thermostat
2nd Stage
Contact (NO)
Stop Button Light (Error Light)
Flame Rod
Burner
Ground
Spark
Plug
Air Pressure
Switch (NO)
Gas Light (L6)
2nd Stage
Valve
Motor Relay
Contact (NO)
Start Button Light
Air Light
(L7)
Solenoid
Valve
1st Stage
Valve
Logic Relay
Coil
Logic Relay
Contact
LN
Motor Relay
Contact (NO)
Stop Button (NC)Start Button (NO)
FuseLight
Logic Relay
Fuse
Contact
Start Button (N C)
Inducer
Output
Thermostat
Input
Pressure
Switch
Valve
Power
120 VAC Input
(Hot)
Valve
Neutral
120 VAC
Neutral
Alarm
Remote
Flame Sensor
Burner Ground
High Voltage
Output
S1505B Manual 974-9308 Rev. 4.32; Aug 29 2014 Page 23
Thermostat
LOHI
Jumper
WHITE
BROWN
BLACK
1- BLACK
120VAC
2 - BLUE
NEUTRAL
Thermostat Cable Plug
BLUE
FRONT VIEW
4 - WHITE
STAGE I I
3 - BROWN
STAGE I
Page 24 S1505B Manual 974-9308 Rev. 4.32; Aug 29 2014
LPG - PROPANE FUEL
VAPORIZATION RATE
The following chart shows the amount of BTU's that various sizes of
tanks will produce on the average at specific temperatures and
regular atmospheric conditions.