A. O. Smith GB-1300 Service Manual

SERVICE HANDBOOK

TABLE OF CONTENTS

PAGE

Introduction. ........................................... 2

Installation

Clearances ........................................... 3

Air Requirements .................................. 3

Contaminated Air .................................. 4

Flammable............................................ 5

Gas Pressure........................................ 5

Venting ................................................. 6

Location of Parts ................................. 16

Central Control Boards ....................... 20

Genesis Wiring ................................... 21

Water Piping ....................................... 25

Genesis Pumps .................................. 26

Stage Parts Information ...................... 27

Dip Switches ...................................... 28

Ignition Control Board ......................... 29

Control Systems Specifications .......... 30

Sequence of Operation

Mechanical ......................................... 31

Electrical ............................................. 33

Setting System Configuration

CCB Switches and Jumpers............... 35

ICB Jumpers ....................................... 36

Connections ....................................... 37

System Display Board ........................ 43

Fault Conditions.................................. 45

PAGE

Troubleshooting

Error Codes

"00" Communication Fault ................ 49

"010" ECO/High Limit Open.............. 50

"01" No Gas Valve Power Sensed .... 51

"020" Low Water Cut Off.................... 52

"030" Circulate Fault ......................... 53

"04" Insufficient Air............................ 54

"060" Insufficient Blocked Flue ......... 55

"070" Power Vent Failure .................. 56

"08"Igniter Failure ............................. 57

"090" Low Gas Failure ...................... 58

"10" Excess Manifold Gas Pressure . 59

"11" Gas Valve Relay Failed ............. 60

"12" Flame Failure ............................ 61

"131-133" Temperature Probe

Faults ...................................... 62

"140" Gas Valve Failure .................... 63

"210" CPU Failure ............................ 64

General Information ............................. 65

Start-Up Instruction ............................. 66

Product Information Tables ................. 67

GENESIS SERVICE HANDBOOK INTRODUCTION

This service handbook is designed to aid in servicing and troubleshooting A.O. Smith Genesis
water heaters in the field. No duplication or reproduction of this book may be made without the
express written authorization of the A.O. Smith Water Products Company.
The following text and illustrations will provide you with a step-by-step procedure to verify
proper installation, operation, and troubleshooting procedures. Additional quick reference data
is included to assist you in servicing this product.
The information contained in this handbook is designed to answer commonly faced situations
encountered in the operation of the Genesis product line and is not meant to be all-inclusive. If
you are experiencing a problem not covered in this handbook, please contact the A.O. Smith
Customer Care Center at 1-800-527-1953 or your local A.O. Smith Water Products Company
representative for further assistance. This handbook is intended for use by licensed plumbing
professionals and reference should be made to the instructional manual accompanying the
product. This handbook contains supplemental information to the Genesis instructional manual.

Qualifications: Installation or service of this water heater requires

the ability equivalent to that
of a licensed tradesman in the field involved. Plumbing, air supply, venting, gas supply, and
electrical skills are required.

Tools Required:

· powered screwdriver

· crosstip screwdriver

· a pipe wrench

· a set of marked drill bits

· an electrical multimeter tester capable of measuring continuity and
voltage

· gas pressure gauge or manometer

· water pressure gauge

· draft gauge

· thermometer ( range 0 - 220 degree F)

· a 1/2 inch drive socket set (USA)

· wire terminals and appropriate tools if electrical repairs are to be made

· 3/16" Allen wrench

· PIO 5/16" nut drive

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INSTALLATION

Electrical circuit boards are accessible through panels on the left end or top left of the jacket.
Blowers, blower air shutters and gas valves are accessible through the upper, front panels.
Burners, hot surface igniters and flame sensors are accessible through the lower, front panels.

Interior Clearances to Combustibles

These Genesis heaters are approved for installation on noncombustible flooring. They can be
installed in an alcove with minimum clearances to combustibles of:

Minimum Clearances to Combustibles

Blank

Top

All Models 6" (152MM) 12" (304MM)

Note: Approximately 24" is suggested as a service clearance to the front of the unit and 24" from
ends of the unit. Also, sufficient clearance on the return end (blank or pump side) is suggested to
permit access to heat exchanger tubes for cleaning.

Water Side

Side

3" (76MM)

Rear Vent Front

3" (76MM) 6" (152mm) Alcove

AIR FOR COMBUSTION

12.5 Cu. Ft.

1,000

1,000

Requires

BTU

BTU

Of Gas

Of Gas

Complete combustion requires 10 cubic feet of air per 1000 BTUH gas input. The National
Fuel Gas Code also recommends an additional 2.5 cu.ft. of “excess” air.
The National Fuel Gas Code also specifies minimum make-up air opening sizes for various
building installations. (Ref: NFPA 54/ANSI Z223.1 ) . See the installation manual for

details.

In calculating the free area of a vent opening, the blocking effect of screens, louvers and grills should
be considered. Screens shall not be of a mesh smaller than ¼ inch square. If the free area is not
known, the latest edition of National Fuel Gas Code NFPA 54/ANSI Z223.1 recommends using figures
of 20-25 percent free area for wood louvers or 60-75 percent for metal grills or louvers.

Of Supply

Air At

Sea Level

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AIR FOR COMBUSTION

DOWNDRAFT

Insufficient make-up air is a major cause of combustion problems. One common example is a mechanical
room where exhaust vent equipment was not considered in sizing make-up air requirements. This may
result in air being pulled down the exhaust vent of the Genesis causing flue gas spillage, flame roll out,
improper combustion, and/or erratic heater shut down. It can also cause the production of carbon monoxide
that could result in serious personal injury or death. In order to assure proper operation, perform a worst
case depressurization test as outlined on Appendix H of the 1999 Edition of the National Flue Gas Code
(ANSI Z223.1/NFPA-54).

AIR FOR COMBUSTION

CONTAMINATED AIR

Along with adequate make-up air, the quality of the air is important. Contaminants in combustion air can
lead to premature heater failure. Vapors from bleaches, soaps, salts, etc
chamber with the make up air and, once fired, mix with water vapor in the gases to form extremely corro­sive hydrochloric or hydrofluoric acid and other corrosive by-products. Dust drawn in may build up on the
blower or clog the main burner ports. Also, be certain to examine the exterior area around the air intake of
a direct vent installation for these contaminants.

. are drawn into the combustion

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AIR FOR COMBUSTION

FLAMMABLE ITEM

Flammable items or pressurized containers or any other potentially hazardous articles must never be
placed on or adjacent to the heater. Open containers of flammable material should not be stored or used
in the same room with the heater or in the area of the exterior air intake of a direct vent installation. Direct
venting does not eliminate the need to remove flammable or corrosives from the area surrounding the

heater.

SUPPLY GAS PRESSURES

GENESIS II

The supply gas pressure is normally
measured at the dirt leg or at the gas
pressure tapping on the supply side
of a gas valve. This reading must be
measured with ‘flowing’ gas.

Manifold gas pressure is measured
at the manifold pressure tap on the
outlet side of each gas valve when
the gas is flowing.

See “Gas Connections” section of
the installation and operation manual
to verify proper gas supply piping
installation.

Supply Gas Pressure

Manifold Gas PressureGas Type

Maximum Minimum

Inches

W.C. kPa

Inches

W.C. kPa

Inches

W.C. kPa

13.8 3.49 6.0 1.22 Natural 3.5 0.87

13.8 3.49 11.0 2.74 Propane 10.0 2.49

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EXTERIOR VENT CLEARANCES

CATEGORY I INSTALLATION

This illustrates the exterior roof clearances for Genesis unit with vertical draft venting. A gas
vent shall terminate above the roof surface with a listed cap or listed roof assembly. All other
gas vents shall terminate not less than 3 ft (0.6 m) above the highest point where they pass
through the roof and at least 2 ft (0.6 m) higher than any portion of a building within 10 ft. (3.1
m). (NFPA 54/ANSI Z223.1)
Section 7.6.2 "within 8 ft (2.4m) with listed caps for vents of 12 inches diameter or smaller".

“Copyright by the American Gas Association. Used by permission of the copyright holder”.

When installed as a direct vent system, follow the manufacturer’s recommended clearances.

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VENT TERMINATION

VENTING

MULTIPLE HEATERS

(When installed as a Category I Appliance)

For larger applications, Genesis water heaters can
be commonly vented together either in a tapered
manifold or constant size manifold. (Follow National
Fuel Gas Code requirements for sizing and
installation.)

Vent Terminations Installation Clearances Per Manufacturers Recommendations -

Sidewall

1. Do not exhaust over a public walkway.

2. Exhaust 6 feet horizontally from gas or electric meter and 48" below or 24" above.

3. Exhaust a minimum of 48" from any soffit or eve vent.

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MULTI-VENTING CONFIGURATIONS

GENESIS 1000-2500 MODELS

Horizontal Sidewall Direct Venting Rear

Intake/Exhaust

Vertical Direct Venting Top Exhaust

Horizontal Venting With Vertical

Combustion Air Intake Top Intake/Rear

Exhaust

Horizontal Sidewall Venting Rear Exhaust Conventional Vertical Venting Top Exhaust

Horizontal Venting With Horizontal

Combustion Air Intake Rear Intake/Top

Exhaust

Venting Options for The Genesis:

May be vented from the top or rear of the unit.
May be vented vertically or horizontally.
May use room air or be direct vented. (Air intake is on rear of cabinet only.)
Vertical vent, non-direct is Category I. May be common vented - Barometric Draft Control required.
Horizontal vent and direct vent are Category III. May NOT be common vented with other appliances.

Use Barometric draft
Regulator to maintain

-.02 to -.04 draft if
necessary.

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Return End of Genesis

GENESIS II VENTING

GENESIS 1000-2500 MODELS

The Genesis boiler may be individually vented vertically up to 35 feet without a barometric damper.
Individual vents with an overall height of more than 35 feet require a barometric. Properly sized vent
material and the use of a barometric damper (when required) will lead to proper vent operation. A
barometric damper is required when draft exceeds -0.04 inches water column. When installed and
adjusted properly, a barometric damper will maintain draft between -0.02" and -0.04" W.C... ensuring
proper operation. Recommend to use "Fan Assisted" tables in NFGC to size vent - Category I.

Inches mm

GW/B-1000 10 254 70
GW/B-1300 12 305 70
GW/B-1500

12 305 70
GW/B-1850 14 355 40
GW/B-2100 14 355 40
GW/B-2500 16 406 40
Kits contain AL-29-4C vent material.

Horizontal Venting Information Table

Model Heater

Vent size

Room Air Intake + Single

Exhaust Vent Pipe Max.

Equivalent Feet

A 90° elbow = 10 equivalent feet of pipe; a 45° elbow = 5 equivalent feet.

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STANDARD VENT - VERTICAL (CATEGORY I)

IMPORTANT!

VENT PRESURE MUST BE MAINTAINED

BETWEEN -0.02" W.C. AND -0.04" W.C. AT

24" (61.0 cm) ABOVE BOILER COLLAR.

* Extending venting over 70 feet (21.3 m) may require special considerations. A 90 elbow = 10 equivalent
feet of pipe; a 45° = 5 feet.

APPLIANCE CERTIFIED EXHAUST MAXIMUM LENGTH WITHOUT

MODEL CATEGORY VENTING VENT SIZE BAROMETRIC DAMPER (FEET)

MATERIAL (INCHES)

TYPE B OR 10”(25.4 cm) 35 Feet (10.7 m) without damper

EQUIVALENT *70 Feet (21.3 m) max. with damper

1300 53RO B EPYT Feet (10.7 m) without damper
1500 EQUIVALENT 12" (30.5 cm) *70 Feet (21.3 m) max. with damper

1850 TYPE B OR 14"(35.6 cm) 35 Feet (10.7 m) without damper
2100 EQUIVALENT *70 Feet (21.3 m) max. with damper

TYPE B OR 16" (40.6 cm) 35 Feet (10.7 m) without damper

EQUIVALENT *70 Feet (21.3 m) max. with damper

I

I

I

I

I000

2500

• Connection for the appliance exhaust vent to the stack must be as direct as possible. Maximum and minimum
venting length for Category I appliances shall be determined per the latest edition of the National Fuel Code (U.S.)
and CAN/CSA-B149.1 and .2 Installation Code (Canada).

STANDARD VERTICAL VENTING (CATEGORY I)

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STANDARD VENT - HORIZONTAL (CATEGORY III)

WARNING: No substitutions of flue pipe or vent cap material are allowed. Such substitutions would jeopardize
the safety and health of inhabitants.

• A maximum of two elbows can be used on inlet and outlet vent piping respectively. Each 90° elbow is equal to 10
feet (3 M) of straight pipe.

APPLIANCE CERTIFIED EXHAUST MAXIMUM

MODEL CATEGORY VENTING VENT SIZE VENT LENGTH

MATERIAL (INCHES) (FEET)

STAINLESS

STEEL AL 29-4C

1300 STAINLESS
1500 STEEL AL 29-4C

1850 STAINLESS
2100 STEEL AL 29-4C

STAINLESS

STEEL AL 29-4C

III

III

III

III

I000

2500

10”(25.4 cm)

12" (30.5 cm)

14"(35.6 cm)

16" (40.6 cm)

70' (21.3 m)

70' (21.3 m)

40' (21.3 m)

40' (21.3 m)

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DIRECT VENT - VERTICAL (CATEGORY I)

DIRECT VENT (VERTICAL EXHAUST CONFIGURATIONS)

APPLIANCE CERTIFIED EXHAUST VENT MAXIMUM AIR INTAKE AIR INLET MAXIMUM

MODEL CATEGORY EXHAUST VENT SIZE EXHAUST VENT MATERIAL SIZE AIR INTAKE

MATERIAL (IN) LENGTH (FT) (IN) LENGTH (FT)

GAL. STEEL

RO SBA ,CVPI

CPVC

GAL.STEEL

RC SBA ,CVPI

CPVC

GAL. STEEL

RO SBA ,CVPI

CPVC

GAL. STEEL

RO SBA ,CVPI

CPVC

GAL. STEEL

RO SBA ,CVPI

CPVC

TYPE B OR

EQUIVALENT

TYPE B OR

EQUIVALENT

TYPE B OR

EQUIVALENT

TYPE B OR

EQUIVALENT

TYPE B OR

EQUIVALENT

10"

(25.4 cm)

12"

(30.5 cm)

14"

(35.6 cm)

14"

(35.6 cm)

16"

(40.6 cm)

35'

(10.7 m)

35'

(10.7 m)

20'

(6.1 m)

20'

(6.1 m)

20'

(6.1 m)

35'

(10.7 m)

35'

(10.7 m)

20'

(6.1 m)

20'

(6.1 m)

20'

(6.1 m)

8"

(20.3 cm)

10"

(25.4 cm)

10"

(25.4 cm)

12"

(30.5 cm)

12"

(30.5 cm)

• The vent should be installed so as to prevent the accumulation of condensate and, where necessary, have means
provided for drainage of condensate. The horizontal breaching of a vent must have an upward slope of not less than
1/4 inch per linear foot (2 cm/m) from the boiler to the vent terminal. The horizontal portion of the vent shall be
supported to maintain clearances and to prevent physical damage or separation of joints.

I000

1300

1500

1850

2100

2500

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WARNING: No substitutions of flue pipe or vent cap material are allowed. Such substitutions would
jeopardize the safety and health of inhabitants.

• A maximum of two elbows can be used on inlet and outlet vent piping respectively. Each elbow is equal to 10 feet
(3 m) of straight pipe.

TABLE 10. DIRECT VENT (HORIZONTAL EXHAUST CONFIGURATIONS)

APPLIANCE CERTIFIED VENT MAXIMUM AIR INTAKE AIR INLET MAXIMUM

MODEL CATEGORY EXHAUST VENT SIZE VENT LENGTH MATERIAL SIZE AIR INTAKE

MATERIAL (INCHES) (FEET) (INCHES) LENGTH (FEET)

GAL. STEEL

RO SBA ,CVPIII

CPVC

GAL.STEEL

RC SBA ,CVPIII

CPVC

GAL. STEEL

RO SBA ,CVPIII

CPVC

GAL. STEEL

RO SBA ,CVPIII

CPVC

GAL. STEEL

RO SBA ,CVPIII

CPVC

I000

1300

1500

1850

2100

2500

AL29-4C

STAINLESS

(SEALED)

AL29-4C

STAINLESS

(SEALED)

AL29-4C

STAINLESS

(SEALED)

AL29-4C

STAINLESS

(SEALED)

AL29-4C

STAINLESS

(SEALED)

10"

(25.4 cm)

12"

(30.5 cm)

14"

(35.6 cm)

14"

(35.6 cm)

16"

(40.6 cm)

35'

(10.7 m)

35'

(10.7 m)

20'

(6.1 m)

20'

(6.1 m)

20'

(6.1 m)

35'

(10.7 m)

35'

(10.7 m)

20'

(6.1 m)

20'

(6.1 m)

20'

(6.1 m)

8"

(20.3 cm)

10"

(25.4 cm)

10"

(25.4 cm)

12"

(30.5 cm)

12"

(30.5 cm)

DIRECT VENT - HORIZONTAL (CATEGORY III)

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EXTENDED SIDEWALL VENTING (POWER ASSIST)

Model #

Vent Outlet

Size (Inch)

Vent Pipe

Size (Inch)

Max. Equivalent

Feet of Vent

Piping

Certified Venting

Category

Approved Venting

Material

GB/GW-1000 10 10 110 Category III

AL29-4C Stainless

Steel (Gas Tight)

GB/GW-1300, 1500 12 8 100 Category III

AL29-4C Stainless

Steel (Gas Tight)

GB/GW-1850 14 10 100 Category III

AL29-4C Stainless

Steel (Gas Tight)

GB/GW-2100 14 10 100 Category III

AL29-4C Stainless

Steel (Gas Tight)

GB/GW-2500 16 10 100 Category III

AL29-4C Stainless

Steel (Gas Tight)

Extended Horizontal Sidewall Venting

EXTENDED SIDEWALL VENTING (POWER ASSIST)

Model #

Vent Outlet

Siz e (Inch)

Vent Pipe

Siz e (Inch)

Max. Equivalent Feet

of Ven t/Combustion

Air Piping

Certified Venting

Category

Approved V enting

Material

Combusti on Air

Inl et Pipe Size

(Inch)

Approved

Combusti on Air Inlet

Material

GB/ GW-1000 10 10 60'/60' Cat egory III

AL29-4C Stainless

Steel (Gas Tight )

8

Galvanized St eel,

PVC, ABS, CPVC

GB/ GW-1300, 1500 12 8 60'/60' Cat egory III

AL29-4C Stainless

Steel (Gas Tight )

10

Galvanized St eel,

PVC, ABS, CPVC

GB/ GW-1850 14 10 60'/60' Cat egor

y I II

AL29-4C Stainless

Steel (Gas Tight )

10

Galvanized St eel,

PVC, ABS, CPVC

GB/ GW-2100 14 10 60'/60' Cat egory III

AL29-4C Stainless

Steel (Gas Tight )

12

Galvanized St eel,

PVC, ABS, CPVC

GB/ GW-2500 16 10 60'/60' Cat egory III

AL29-4C Stainless

Steel (Gas Tight )

12

Galvanized St eel,

PVC, ABS, CPVC

Extended Horizontal Direct Venting

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GENESIS POWER VENT WIRING DIAGRAM

Electrical power to the power venter must be supplied by the installer and wired according to the Wiring
Diagram. Wiring must comply with the wiring diagram in order for the boiler to function properly. The
wiring is part of the boiler's safety circuit and shuts off the boiler if the Fan Proving Switch at the power
venter is not made.

The Genesis II Control System is also set to shut off the power venter when there is no "call for heat".
A normal condition for the boiler's Display Board is for the Power Venter Red LED to remain lit while the
unit is in a Standby mode. Awaiting another "call for heat". Once a "call for heat" is generated, the
Control System will start a Firing sequence by starting all of the

blowers inside the unit and at the same
time send a 24 VAC signal and a 24 VAC return (terminals 7 & 6 of the Genesis II External 24 VAC
Distribution Box) to the power venter to turn its fan motor on utilizing relay R1 at the Power Venter
Electrical Box. Once the Power Venter fan gets up to speed and makes the fan proving switch, the 24
VAC signal is routed back to the boiler and can be measured between terminals 5 and 6 at the Genesis
II External 24 VAC Distribution Box. The returning 24 VAC signal will then extinguish the previously lit
Red LED and the unit will continue its Normal Pre-purge mode and then light the boiler.

Any failure will shutoff the boiler and the power venter off after the Post-purge Cycle

is completed. The
failure that caused the shut down will be displayed at the Display Board and a Lockout message and
error code will be displayed. Remember that when the Power venter is not running, the Red LED
indicator for the Power Venter will also be displayed; so troubleshoot the other indicators first before
suspecting the Power Venter. If the cause of the failure is the Power Venter, then the only Red LED lit
will be its own and the Display Message will be "Lock-Out 070" ---the error code for a Power Venter
Failure.

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LOCATION OF PARTS

Rear Air

Intake

Junction Box

120V

Rear or Top Vent
Connection

24V

Back of Heater

Pump Ground Terminal 1 Green
Pump Neutral Terminal 2 White
Pump 120VAC Hot Terminal 3 Black
Ground Input Terminal 4 Green
120VAC Neutral Input Terminal 5 White
120VAC Hot Input Terminal 6 Black

Tank Probe Terminal 1 Yellow
Tank Probe Terminal 2 Yellow
Ext. TSTAT Terminal 3 Blue Black
Ext. TSTAT Terminal 4 Black White
Power Vent Terminal 5 Yellow Red
Prover Switch
Power Vent Terminal 6 White Black
Prover Switch
Power Vent Terminal 7 Red White
Prover Switch

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Press Relief Valve

GW-125 PSI

GB-50 PSI

Open Electrical Access Door

LOCATION OF PARTS

Manual Gas Shutoff

On/Off
Switch

Water
Inlet

Water
Outlet

Electrical Access
Door

Stage 1 ICB

Stage 2 ICB

Stage 3 ICB

Central Control Board
(CCB) - on bottom of
cabinet

Transformer
120-Top Terminal
24-Lower terminal

TB6
Grounds

TB5 24V Neutral

TB7 120V Neutral

TB4
120V
Hot

TB3

TB2

TB1

Torque

Bolts

to

15 lbs.

Sight Glass

Water
Inlet

Water
Outlet

Flow Switch

Fuses
F 1 ,F2 ,
F3

Pump
Relay

TB = TERMINAL BOARD
CCB = CENTRAL CONTROL
BOARD
ICB = IGNITION CONTROL
BOARD

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LOCATION OF PARTS

Low Gas Pressure
Switch closes at 5.0
± .4 " W.C.
positive pressure

Blower Prover Connects to

Back Port of Switch
(negative pressure)

Flame
Sensor

Blower Prover

Connects to Front Port of

Switch

(positive pressure)

Blower
Air

Draft

Diffuser

Plate

Set Air Shutter to

1.6"W.C.

White Rogers
36c68

Robert Shaw
DERHC-7000

Fasco

7082-6433

Blower

Blower Prover ­Differential
Pressure Switch

Rear Hose Connects

to Rear Port of Switch

and Main Burner

(negative pressure)

HSI

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LOCATION OF PARTS

Blocked Flue Switch
Located Behind Blower - Left
of Exhaust Vent .60± .05"W.C.
Open

Combustion Air Intake

Flue

Fasco Air

Shutter Set to

1.2" W.C. on
Back Hose

Teed Into

Rear Hose of

Blower

Prover Switch

to Set Air

Shutter

Front Hose -

Positive Press

Rear Hose -

(negative
pressure)

Blower Prover

(Differential)

Pressure Switch

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Flame

Sensor

Hot Surface Ignitor
(HSI)

24 VAC

Transformer

Combustion

Blower

Line

Gas

Board to
Board Gas
Valves

To Next ICB

From

Previous

Stage ICB

(To and from

connections

are

interchangable)

J24

J26

J27

CN2

CN6

CN8

CN14

CN5

CN12

CN1

CN7

Green

CN15

5A

Red

CN11

CN3

CN13

CN4

CENTRAL

CONTROL

BOARD

(CCB)

JUNCTION BOX

IGNITION

CONTROL

BOARD

(ICB)

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GENESIS WIRING DIAGRAM

ELECTRICAL CONNECTION DIAGRAM - 1 of 4

ICB2 WIRING SAME AS ICB1

ICB4 WIRING SAME AS ICB3

1,000,000 THRU 2,500,000

30 AMP C.B. CIRCUIT

120 VAC 60 HZ

10 AMP

FUSE F1

POWER SWITCH

ON/OFF

TB4-6

EXT 120

D-BOX-6

TB4

1 HOT

L

FLAME SENSOR

IGNITER PROVING

LED

ICB #1

CN1-1

CONTACTOR RELAY

CONTROL BOX

L1 IN

K1

FUSE F5

LED

CURRENT

G

IN 0

CURRENT

K6

K2

20 AMP

D-BOX

IGNITOR

STAGE #1

D-BOX-2

L2 IN

EXT 120

D-BOX-3

CN6-1

CN5-2

CN5-1

L1

L2

CN17-1

CN1-2

CN17-2

INPUT

FLAME SENSOR

STAGE #1

#1

BLOWER

PUMP

L4

L5

EXT 120

#5

EXT

120

TB7

L

2 NEUT.

EXT

#4

D-BOX

120

TB6

L

3 GND.

10 AMP

FUSE F3

LED

FLAME SENSOR

ICB #3

IGNITER PROVING

CN1-1

L1 IN

CURRENT

CURRENT

G

LED

IN 0

K6

K2

NOT USED

L2 IN

L1

L2

CN17-2

CN17-1

CN1-2

CN5-1

CN5-2

CN6-1

FLAME SENSOR

STAGE #3

BLOWER

#3

22

stcudorP retaW htimS .O .A Service Workbook

Ashland City, Tennessee 2005© Training Department

24VAC IN

L1 IN

TB4-6

24VAC IN

24VAC IN

K1 PUMP

L

1 HOT

TB5

RELAY

K4

K4

SECONDARY 24 VAC

PRIMARY 120 VAC

CCB

CN9

CN9

CN8-4

CN12-3

CN12-1

CN7-1

CN4-4

CN4-4

K4

+

+

IRI *

VALVE

GAS

3 AMP FUSE

ICB #2

ICB #1

3 AMP FUSE

CN9

5 AMP FUSE

CN10

R

LED

LED

R

CN10

CCB

LED

LED

IN 0

K5

CN10

R

LED

G

GAS

VALVE

TRANSFORMER T1

CONTROL BOX

24VAC NEUT. IN

24VAC NEUT. IN

24VAC NEUT. IN

CN4-3

CN13-6

CN13-3

CN13-3

CN13-6

CN4-3

CN12-5

CN12-4

CN7-2

IRI *

VALVE

BLEED

CN8-3

_

-

L2 IN

RELAY*

STAGE #2

VALVE/S

GAS

VALVE/S

STAGE #1

K2 IRI G.V.

IRI *

GAS

2 NEUT.

L

TB7

TB5

K3

CN15-1

CN16-1

CN15-2

CN16-2

CN15-2

CN16-2

K7

CN15-1

CN15-1

CN16-1

K3

GAS VALVE
24VAC HOT

GAS VALVE
24VAC HOT

GAS VALVE
24VAC HOT

GAS VALVE
24VAC HOT

GAS VALVE
24VAC HOT

24VAC NEUT.

GAS VALVE

24VAC NEUT.

GAS VALVE

CN15-2

ICB3 AND ICB4 WIRING
SAME AS ICB1 AND ICB2

ELECTRICAL CONNECTION DIAGRAM - 2 of 4

CCB=Central Control Board
ICB=Ignition Control Board
ECO=Energy Cut Off
LWCO=Low Water Cut Off
IRI=Industrial Risk Insurance
CPU=Central Processing Unit
CSD1=Control Safety Devices - 1