XSol Diagnostic System

Interactive Test Sequence Navigator

Welcome to the XSol Diagnostic System

This system provides interactive diagnostic tests with proper sequence navigation based on the decoded .seq file logic.

Start Diagnostic Sequence

or choose a specific test below:

WORCESTER I JUNIOR

GLOBALLY REPLACED

Next: &18, *

OVERRUN OPERATION

SELECTOR SWITCH TO CH - MAX POSITION

Next: &nff, f162

CH MODULATION

ATTACH A U-GAUGE TO

Next: &2, f159

SYSTEM PRESSURE RISE

Next: &3, !f158

CH OPERATION

ATTACH A U-GAUGE TO

Next: &4, ?148, ?150, ?152, ?559

DHW MODULATION

ATTACH A U-GAUGE TO THE GAS VALVE BURNER PRESSURE TEST POINT

Next: &5, f143

DHW OPERATION

Next: &6, ?129, ?131, ?133, ?135

AUTO FROST PROTECTION

Next: &7, f126

DHW MAXIMUM GAS PRESSURE

Next: &199, f104

BURNER ESTABLISHES AT MINIMUM PRESSURE

ATTACH A U-GAUGE TO

Next: &10, ?86, ?88, ?90

DHW FAN RUNS

CH POTENTIOMETER SET TO MINIMUM

Next: &349, f465

DHW FLOW RATE

Next: &365, f1155

WORCESTER I JUNIOR

CASE REMOVAL<

Next: &283, !f1

CH BURNER IGNITES

SELECTOR SWITCH TO CH - MAX POSITION

Next: &8, f200

OBSERVATION BOILER STANDBY

ENSURE NO CH OR DHW DEMANDS

Next: &1153, ?932, ?934, ?936

THE APPLIANCE SEQUENCE

Next: &nff, !f287

DHW SPARKING

REMOVE INNER CASING COVER
CH POTENTIOMETER SET TO MINIMUM

Next: &423, f687

CH DEMAND PUMP RUNS

CH TEMPERATURE CONTR

Next: &14, f366

DHW BURNER IGNITES

CH POTENTIOMETER SET TO MINIMUM

Next: &nff, f402

DHW BURNER IGNITES

CH POTENTIOMETER SET TO MINIMUM

Next: &11, f424

FURTHER INVESTIGATION MELTED APS

PAGE OUTSIDE THE MODEL

Next: &nff, f549

FUSE INVESTIGATION TREE

OUTSIDE MODEL

Next: &nff, f1131

MODEL TYPE

Next: &16, !f1154

CASE OFF

CASE OFF

Next: End

SLOW FLASH NO POWER TO EXT CONTROLS

PCB CONTROL BOARD

Next: End

SLOW FLASH NO POWER TO PUMP

PCB CONTROL BOARD

Next: End

SLOW FLASH RUNNING SLOW

PUMP AND HARNESS ASSEMBLY

Next: End

SLOW FLASH BOTH PRESSURES OUT

INLET PRESSURE

Next: End

SLOW FLASH NO POWER TO MODUREG

PCB CONTROL BOARD

Next: End

SLOW FLASH MODUREG RESISTANCE

GAS VALVE

Next: End

SLOW FLASH MAXIMUM OUT

INLET PRESSURE

Next: End

SLOW FLASH MINIMUM OUT

INLET PRESSURE

Next: End

SLOW FLASH NOT MODULATING DHW

THERMISTOR SENSOR (DHW)

Next: End

SLOW FLASH NOT MODULATING

THERMISTOR SENSOR (CH)

Next: End

SLOW FLASH OVERHEAT INVESTIGATION

BY-PASS PIPE ASSEMBLY

Next: End

FAST FLASH FIRES WITH NO DEMAND

PCB SERVICE POTENTIOMETER

Next: End

FAST FLASH

THERMISTOR SENSOR (DHW)

Next: End

FAST FLASH

THERMISTOR SENSOR (CH)

Next: End

FAST FLASH POSITIONING

HARNESS (MAIN)

Next: End

DHW MAXIMUM GAS PRESSURE

THERMISTOR SENSOR (DHW)

Next: End

FAST FLASH INCORRECT RESISTANCE

FAN ASSEMBLY

Next: End

FAST FLASH SHORT CCT

FLOW SENSOR (VENTURI)

Next: End

FAST FLASH SHORT CCT

AIR PRESSURE SWITCH

Next: End

FAST FLASH OPEN CCT

AIR PRESSURE SWITCH

Next: End

FAST FLASH APS OPEN CCT

HARNESS (MAIN)

Next: End

DHW MAXIMUM GAS PRESSURE

DHW FLOW SWITCH

Next: End

FAST FLASH OPEN CCT

FLOW SENSOR (VENTURI)

Next: End

FAST FLASH OPEN CCT

FLUE

Next: End

BOILER STANDBY

FROST PROTECTION

Next: End

BOILER STANDBY

OPEN TAP OR LEAK

Next: End

BOILER STANDBY

Next: End

BOILER STANDBY

PROGRAMMER

Next: End

BOILER STANDBY - FROST PROTECTION

THERMISTOR SENSOR (CH)

Next: End

CH DEMAND PUMP RUNS

FUSE (MAINS)

Next: End

CH DEMAND PUMP RUN

FUSE T2A

Next: End

DHW MAXIMUM GAS PRESSURE

INLET PRESSURE

Next: End

25 AMP).CH DEMAND PUMP RUN

FUSE T1.25A

Next: End

FUSE INVESTIGATION

FAN ASSEMBLY

Next: End

FUSE INVESTIGATION GAS VALVE

GAS VALVE

Next: End

FUSE INVESTIGATION

PUMP AND HARNESS ASSEMBLY

Next: End

FUSE INVESTIGATION

TRANSFORMER

Next: End

MODEL TYPE

Z REDIRECTION

Next: End

CLOSED

SERVICE VALVE

Next: End

DHW FLOW RATE

FLOW FILTER RESTRICTOR

Next: End

DHW FLOW RATE

WATER SUPPLY

Next: End

BURNER ESTABLISHES BUT BAFFLES

MAIN BURNER INJECTOR

Next: End

BURNER ESTABLISHES BUT BAFFLES

HEAT EXCHANGER (FLUE WAYS)

Next: End

DHW OPERATION

HEAT EXCHANGER (FLUE WAYS)

Next: End

DHW OPERATION

FLUE

Next: End

DHW OPERATION

MAIN BURNER INJECTOR

Next: End

DHW MODULATION

THERMISTOR SENSOR (DHW)

Next: End

SYSTEM PRESSURE RISE

EXPANSION VESSEL

Next: End

CH MODULATION

THERMISTOR SENSOR (CH)

Next: End

AUTO FROST PROTECTION

THERMISTOR SENSOR (CH)

Next: End

CH BURNER IGNITES

THERMISTOR SENSOR (CH)

Next: End

CH OPERATION

THERMISTOR SENSOR (CH)

Next: End

OVERRUN OPERATION

THERMISTOR SENSOR (CH)

Next: End

GAS VALVE 3 (RESISTANCE)

GAS VALVE

Next: End

DUMMY

APPLIANCE SEQUENCE

Next: End

BURNER IGNITES

SYSTEM PRESSURE

Next: End

BURNER IGNITES

OVERHEAT THERMOSTAT

Next: End

BURNER IGNITES

WATER PRESSURE SWITCH

Next: End

GAS VALVE 1 2 RESISTANCE999

GAS VALVE

Next: End

DHW BURNER IGNITES999

PCB CONTROL BOARD

Next: End

DHW BURNER IGNITES999

INLET PRESSURE

Next: End

DHW BURNER IGNITES999

SPARK ELECTRODE ASSEMBLY (ELECTRODES)

Next: End

BURNER IGNITES1

SYSTEM PRESSURE

Next: End

BURNER IGNITES1

OVERHEAT THERMOSTAT

Next: End

BURNER IGNITES1

WATER PRESSURE SWITCH

Next: End

GAS VALVE 1 2 RESISTANCE9991

GAS VALVE

Next: End

DHW BURNER IGNITES9991

PCB CONTROL BOARD

Next: End

DHW BURNER IGNITES9991

INLET PRESSURE

Next: End

DHW BURNER IGNITES9991

SPARK ELECTRODE ASSEMBLY (ELECTRODES)

Next: End

DHW OPERATION

FAN ASSEMBLY

Next: End

FAN RESISTANCE

FAN ASSEMBLY

Next: End

CH PUMP RUNS

TRANSFORMER

Next: End

FAN DOESNT RUN DHW FLOW SWITCH

PCB CONTROL BOARD

Next: End

MELTED APS STIFF

FAN + AIR PRESSURE SWITCH

Next: End

CH OPERATION

SYSTEM PRESSURE

Next: End

CH OPERATION

PUMP AND HARNESS ASSEMBLY

Next: End

CH MODULATIONCH OPERATION

THERMISTOR SENSOR (CH)

Next: End

CH OP LOCKOUT

BY-PASS PIPE ASSEMBLY

Next: End

MELTED APS

FAN + AIR PRESSURE SWITCH

Next: End

DHW FAN RUNS

FLOW SENSOR (VENTURI)

Next: End

DHW FAN RUNS

AIR PRESSURE SWITCH

Next: End

DHW FAN RUNS

THERMISTOR SENSOR (DHW)

Next: End

DHW FAN RUNS

THERMISTOR SENSOR (CH)

Next: End

DHW FAN RUNS

SYSTEM PRESSURE

Next: End

FAN DOES NOT RUN

OVERHEAT THERMOSTAT

Next: End

FAN NOT RUNNING

WATER PRESSURE SWITCH

Next: End

DHW BURNER IGNITES

FLOW SENSOR (VENTURI)

Next: End

DHW BURNER IGNITES

FLUE

Next: End

DHW BURNER IGNITES

AIR PRESSURE SWITCH

Next: End

DHW SPARKING

FLOW SENSOR (VENTURI)

Next: End

DHW SPARKING

FLUE

Next: End

DHW SPARKING

AIR PRESSURE SWITCH

Next: End

DHW SPARKING

SPARK ELECTRODE ASSEMBLY (LEADS)

Next: End

DHW SPARKING

SYSTEM PRESSURE

Next: End

DHW SPARKING

OVERHEAT THERMOSTAT

Next: End

DHW SPARKING

WATER PRESSURE SWITCH

Next: End

DHW SPARKING APS

HARNESS (MAIN)

Next: End

BURNER ESTABLISHES POOR CONDITION OR GAP

FLAME SENSOR ELECTRODE

Next: End

FLAME SENSE

HARNESS (MAIN)

Next: End

BURNER ESTABLISHES

BURNER

Next: End

BURNER ESTABLISHES

MAIN BURNER INJECTOR

Next: End

DHW FAN RUNS

FLOW FILTER RESTRICTOR

Next: End

AUTO FROST

PCB SERVICE POTENTIOMETER

Next: End

BURNER ESTABLISHES AT MINIMUM PRESSURE

INLET PRESSURE

Next: End

SLOW FLASH STUCK IN FAULT

SYSTEM PRESSURE

Next: End

SLOW FLASH NOT RESETTING

OVERHEAT THERMOSTAT

Next: End

SLOW FLASH

WATER PRESSURE SWITCH

Next: End

SLOW FLASH

SPARK ELECTRODE ASSEMBLY (LEADS)

Next: End

SLOW FLASH CUTTING OUT ON RAMP UP

INLET PRESSURE

Next: End

SLOW FLASH POOR CONDITION OR GAP

FLAME SENSOR ELECTRODE

Next: End

SLOW FLASH FLAME SENSE

HARNESS (MAIN)

Next: End

SLOW FLASH NOT ESTABLISHING

MAIN BURNER INJECTOR

Next: End

SLOW FLASH NOT ESTABLISHING

INLET PRESSURE

Next: End

SLOW FLASH SOLENOID DAMAGED

GAS VALVE

Next: End

SLOW FLASH NO POWER TO GAS VALVE

PCB CONTROL BOARD

Next: End

SLOW FLASH NOT IGNITING

INLET PRESSURE

Next: End

SLOW FLASH NOT IGNITING

SPARK ELECTRODE ASSEMBLY (ELECTRODES)

Next: End

SLOW FLASH OVERHEAT INVESTIGATION

SYSTEM PRESSURE

Next: End

SLOW FLASH NOT RUNNING

PUMP AND HARNESS ASSEMBLY

Next: End

SLOW FLASH BOTH PRESSURES OUT

GAS VALVE

Next: End

SLOW FLASH MODUREG

HARNESS (MAIN)

Next: End

SLOW FLASH MAXIMUM OUT

GAS VALVE

Next: End

SLOW FLASH WRONG VOLTAGE TO MODUREG

PCB CONTROL BOARD

Next: End

SLOW FLASH MINIMUM OUT

GAS VALVE

Next: End

SLOW FLASH NOT MODULATING ON DHW

PCB CONTROL BOARD

Next: End

SLOW FLASH NOT MODULATING ON CH

PCB CONTROL BOARD

Next: End

SLOW FLASH OVERHEAT INVESTIGATION

HEAT EXCHANGER

Next: End

SLOW FLASH NO FAULT

NORMAL OPERATION

Next: End

SLOW FLASH STUCK ON

PCB CONTROL BOARD

Next: End

SLOW FLASH CUTTING OUT EARLY

OVERHEAT THERMOSTAT

Next: End

FAST FLASH FIRING WITH NO DEMAND

PCB CONTROL BOARD

Next: End

FAST FLASH DHW THERMISTOR

HARNESS (MAIN)

Next: End

FAST FLASH CH THERMISTOR

HARNESS (MAIN)

Next: End

FAST FLASH STUCK IN FAULT

PCB CONTROL BOARD

Next: End

FAST FLASH NOT RUNNING WITH POWER

FAN ASSEMBLY

Next: End

FAST FLASH RESISTANCE

FAN HARNESS

Next: End

FAST FLASH NO POWER TO FAN

PCB CONTROL BOARD

Next: End

FAST FLASH APS SHORT CCT

HARNESS (MAIN)

Next: End

FAST FLASH APS SHORTED

Z REDIRECTION

Next: End

FAST FLASH APS OPEN CCT

Z REDIRECTION

Next: End

FAST FLASH NOT RECOGNISING APS SWITCHING

PCB CONTROL BOARD

Next: End

FAST FLASH RUNNING SLOW

FAN ASSEMBLY

Next: End

DHW MAXIMUM GAS PRESSURE

PCB CONTROL BOARD

Next: End

BOILER STANDBY - FROST PROTECTION

PCB CONTROL BOARD

Next: End

BOILER STANDBY - FAN RELAY

PCB CONTROL BOARD

Next: End

CH DEMAND PUMP RUN

Next: End

FUSE INVESTIGATION MAINS

Z REDIRECTION

Next: End

FUSE INVESTIGATION F1

Z REDIRECTION

Next: End

FUSE INVESTIGATION F2

Z REDIRECTION

Next: End

FUSE INVESTIGATION

FAN HARNESS

Next: End

FUSE INVESTIGATION GAS VALVE

HARNESS (MAIN)

Next: End

GAS PRESSURE (INLET)

GAS VALVE

Next: End

FUSE INVESTIGATION

FUSE INVESTIGATION NO FAULT

Next: End

HEAT EXCHANGER (SECONDARY COIL)

HEAT EXCHANGER (SECONDARY COIL)

Next: End

FAN STOPPING DURING DEMAND

PCB CONTROL BOARD

Next: End

DHW BURNER IGNITES

AIR PRESSURE TUBES

Next: End

FAULTY

TEE PIECE

Next: End

DHW FAN RUNS

AIR PRESSURE TUBES

Next: End

FAULTY 2

TEE PIECE

Next: End

DHW SPARKING

AIR PRESSURE TUBES

Next: End

FAULTY 3

TEE PIECE

Next: End

FAST FLASH OPEN CCT

AIR PRESSURE TUBES

Next: End

FAULTY 4

TEE PIECE

Next: End

FAST FLASH SHORT CCT

AIR PRESSURE TUBES

Next: End

FAULTY 5

TEE PIECE

Next: End

DHW OPERATION

PCB CONTROL BOARD

Next: End

DHW MODULATION

GAS VALVE

Next: End

DHW MODULATION

PCB CONTROL BOARD

Next: End

CH OPERATION

Next: End

CH OPERATION

PCB CONTROL BOARD

Next: End

OVERRUN OPERATON

PCB CONTROL BOARD

Next: End

DHW QUIET OPERATION, RADIATORS COLD

HEAT EXCHANGER

Next: End

CH MODULATION

PCB CONTROL BOARD

Next: End

CH SENSOR MODULATION

HARNESS (MAIN)

Next: End

CH SENSOR (FROST PROTECTION)

HARNESS (MAIN)

Next: End

CH SENSOR (BURNER IGNITES)

HARNESS (MAIN)

Next: End

CH SENSOR (CH OPERATION)

HARNESS (MAIN)

Next: End

CH SENSOR (OVERRUN)

HARNESS (MAIN)

Next: End

GAS VALVE 3

HARNESS (MAIN)

Next: End

CH DEMAND PUMP RUN

Next: End

BURNER IGNITES

HARNESS (MAIN)

Next: End

GAS VALVE 1 AND 2999

HARNESS (MAIN)

Next: End

GAS VALVE 1 2 VOLTAGE999

GAS VALVE

Next: End

DHW BURNER IGNITES999

MAIN BURNER INJECTOR

Next: End

BURNER IGNITES1

HARNESS (MAIN)

Next: End

GAS VALVE 1 AND 29991

HARNESS (MAIN)

Next: End

GAS VALVE 1 2 VOLTAGE9991

GAS VALVE

Next: End

DHW BURNER IGNITES9991

MAIN BURNER INJECTOR

Next: End

FAN DOES NOT RUN

FAN ASSEMBLY

Next: End

RESISTANCE

FAN HARNESS

Next: End

CH DEMAND PUMP RUN

PUMP AND HARNESS ASSEMBLY

Next: End

PCB CONTROL BOARD (POTENTIOMETER)

PCB CONTROL BOARD

Next: End

MELTED APS

PCB + AIR PRESSURE SWITCH

Next: End

CH MODULATIONCH OPERATION

PCB CONTROL BOARD

Next: End

CH OPERATION

HARNESS (MAIN)

Next: End

CH OP LOCKOUT

HEAT EXCHANGER

Next: End

CH OPERATION

HEAT EXCHANGER

Next: End

NO FAULT

NORMAL OPERATION

Next: End

CH OPERATION STUCK ON

PCB CONTROL BOARD

Next: End

CH OPERATION

OVERHEAT THERMOSTAT

Next: End

DHW FAN RUNS

Z REDIRECTION

Next: End

DHW THERMISTOR (DHW FAN RUNS)

HARNESS (MAIN)

Next: End

CH SENSOR (DHW FAN RUNS)

HARNESS (MAIN)

Next: End

FAN DOES NOT RUN

PCB CONTROL BOARD

Next: End

FAN NOT RUNNING

HARNESS (MAIN)

Next: End

APS (N/C)

HARNESS (MAIN)

Next: End

DHW BURNER IGNITES

Z REDIRECTION

Next: End

DHW BURNER IGNITES

FAN ASSEMBLY

Next: End

DHW SPARKING

Z REDIRECTION

Next: End

DHW SPARKING

FAN ASSEMBLY

Next: End

DHW SPARKING

SPARK ELECTRODE ASSEMBLY (ELECTRODES)

Next: End

DHW SPARKING

PCB CONTROL BOARD

Next: End

DHW SPARKING OVERHEAT

HARNESS (MAIN)

Next: End

BURNER ESTABLISHES OPEN CCT

FLAME SENSOR ELECTRODE

Next: End

PCB CONTROL BOARD (FLAME SENSE)

PCB CONTROL BOARD (FLAME SENSE)

Next: End

DHW FAN RUNS

DHW FLOW SWITCH

Next: End

AUTO FROST PROTECTION

PCB CONTROL BOARD

Next: End

SLOW FLASH SAFETY CIRCUIT

HARNESS (MAIN)

Next: End

SLOW FLASH STUCK IN FAULT

PCB CONTROL BOARD

Next: End

SLOW FLASH NOT SPARKING

SPARK ELECTRODE ASSEMBLY (ELECTRODES)

Next: End

SLOW FLASH NO SPARKING

PCB CONTROL BOARD

Next: End

SLOW FLASH INCORRECT PRESSURE

GAS VALVE

Next: End

SLOW FLASH OPEN CCT

FLAME SENSOR ELECTRODE

Next: End

SLOW FLASH NOT RECOGNISING FLAME

PCB CONTROL BOARD

Next: End

SLOW FLASH CUTTING OUT

GAS VALVE

Next: End

SLOW FLASH GAS VALVE

HARNESS (MAIN)

Next: End

SLOW FLASH NOT OPENING

GAS VALVE

Next: End

SLOW FLASH NOT IGNITING

MAIN BURNER INJECTOR

Next: End

MINIMUM BURNER PRESSURE INCORRECT

CHARACTERISTIC TEST FROM PRESSURE BURNER MAX AND MIN

Next: p1008

MAXIMUM BURNER PRESSURE INCORRECT

CHARACTERISTIC TEST FROM PRESSURE BURNER MAX AND MIN

Next: p1010

BOTH MAXIMUM AND MINIMUM INCORRECT

CHARACTERISTIC TEST FROM PRESSURE BURNER MAX AND MIN

Next: p1012

BOILER TEMP ABOVE 85 DEGREES, BOILER STILL FIRING

CHARACTERISTIC TEST FROM INSPECTION LOCKOUT TEMPERATURE

Next: !p1042

BOILER GOES TO LOCKOUT UNDER 85 DEGREES

CHARACTERISTIC TEST FROM INSPECTION LOCKOUT TEMPERATURE

Next: !p1044

BOILER DOES NOT FIRE BUT FAULT CODE IMMEDIATELY REOCCURS

CHARACTERISTIC TEST FROM OBSERVATION BOILER RESET FAST FLASH

Next: p1048

BOILER FIRES WITH NO DEMAND

CHARACTERISTIC TEST FROM OBSERVATION BOILER RESET FAST FLASH

Next: p1050

FAN RUNS, PUMP DOES NOT RUN

CHARACTERISTIC TEST FROM OBSERVATION STANDBY OPERATION

Next: p1097

PUMP RUNS, FAN DOES NOT RUN

CHARACTERISTIC TEST FROM OBSERVATION STANDBY OPERATION

Next: p1099

TUBES UNSATISFACTORY

CHARACTERISTIC TEST FROM AIR PRESSURE TUBES

Next: !p1180

TEE UNSATISFACTORY

CHARACTERISTIC TEST FROM AIR PRESSURE TUBES

Next: !p1182

TUBES UNSATISFACTORY

CHARACTERISTIC TEST FROM AIR PRESSURE TUBES

Next: !p1185

TEE UNSATISFACTORY

CHARACTERISTIC TEST FROM AIR PRESSURE TUBES

Next: !p1187

TUBES UNSATISFACTORY

CHARACTERISTIC TEST FROM AIR PRESSURE TUBES

Next: !p1190

TEE UNSATISFACTORY

CHARACTERISTIC TEST FROM AIR PRESSURE TUBES

Next: !p1192

TUBES UNSATISFACTORY

CHARACTERISTIC TEST FROM AIR PRESSURE TUBES

Next: !p1195

TEE UNSATISFACTORY

CHARACTERISTIC TEST FROM AIR PRESSURE TUBES

Next: !p1197

TUBES UNSATISFACTORY

CHARACTERISTIC TEST FROM AIR PRESSURE TUBES

Next: !p1200

TEE UNSATISFACTORY

CHARACTERISTIC TEST FROM AIR PRESSURE TUBES

Next: !p1202

BURNER BAFFLES OUT DURING FULL DEMAND

CHARACTERISTIC TEST FROM DHW OPERATION

Next: p130

HEAT EXCHANGER NOISY (KETTLES) DURING DHW OPERATION

CHARACTERISTIC TEST FROM DHW OPERATION

Next: !p132

DHW COOL, RADIATORS COLD

CHARACTERISTIC TEST FROM DHW OPERATION

Next: p134

DHW QUIET OPERATION, BUT PUMP RUNS AND RADIATORS HEAT

CHARACTERISTIC TEST FROM DHW OPERATION

Next: !p136

RADIATORS HEAT UP BUT HEAT EXCHANGER NOISY (KETTLES)

CHARACTERISTIC TEST FROM CH OPERATION

Next: !p590

SYSTEM DOES NOT HEAT, BUT BOILER REACHES TEMPERATURE

CHARACTERISTIC TEST FROM CH OPERATION

Next: !p151

BURNER PRESSURE DOESN'T RAMP UP, RADIATORS AND BOILER STAY COOL

CHARACTERISTIC TEST FROM CH OPERATION

Next: p153

BOILER GOES TO (OVERHEAT) LOCKOUT ON CH OPERATION

CHARACTERISTIC TEST FROM CH OPERATION

Next: p560

BOILER TEMP ABOVE 85 DEGREES, BOILER STILL FIRING

CHARACTERISTIC TEST FROM INSPECTION LOCKOUT TEMPERATURE

Next: !p596

BOILER GOES TO LOCKOUT UNDER 85 DEGREES

CHARACTERISTIC TEST FROM INSPECTION LOCKOUT TEMPERATURE

Next: !p598

BURNER IGNITES, SPARK STOPS, FLAME DIES AWAY, SPARK RESTARTS

CHARACTERISTIC TEST FROM BURNER ESTABLISHES AT MINIMUM PRESSURE

Next: p87

BURNER FULLY CROSSLIGHTS, SPARK DOESN'T STOP, BOILER LOCKS OUT

CHARACTERISTIC TEST FROM BURNER ESTABLISHES AT MINIMUM PRESSURE

Next: p753

BURNER PRESSURE GOES STRAIGHT TO HIGH PRESSURE

CHARACTERISTIC TEST FROM BURNER ESTABLISHES AT MINIMUM PRESSURE

Next: !p91

INDICATOR LIGHT FLASHING SLOW (ONCE PER SECOND)

CHARACTERISTIC TEST FROM OBSERVATION BOILER STANDBY

Next: p938

INDICATOR LIGHT FLASHING FAST (FOUR TIMES PER SECOND)

CHARACTERISTIC TEST FROM OBSERVATION BOILER STANDBY

Next: p1045

PUMP OR FAN RUN WITH NO DEMAND (NO FAULT CODE)

CHARACTERISTIC TEST FROM OBSERVATION BOILER STANDBY

Next: p937

APPLIANCE RESETS BUT EITHER DOES NOT IGNITE OR FLAME DOES NOT ESTABLISH

CHARACTERISTIC TEST FROM OBSERVATION BOILER RESET SLOW FLASH

Next: p950

BOILER WILL NOT RESET OR RESETS AND RETURNS TO FAULT CODE

CHARACTERISTIC TEST FROM OBSERVATION BOILER RESET SLOW FLASH

Next: !p952

BURNER IGNITES, SPARK STOPS, FLAME DIES AWAY, SPARK RESTARTS

CHARACTERISTIC TEST FROM BURNER ESTABLISHES AT MINIMUM PRESSURE

Next: p962

BURNER FULLY CROSSLIGHTS, SPARK DOESN'T STOP, BOILER LOCKS OUT

CHARACTERISTIC TEST FROM BURNER ESTABLISHES AT MINIMUM PRESSURE

Next: p964

GAS VALVE 3 (RESISTANCE)

REMOVE ONE OF THE BLUE WIRES ATTACHED TO THE MODULATING SOLENOID

Next: !p1019, !f1020

GAS PRESSURE (INLET)

ATTACH A U-GAUGE TO THE GAS VALVE INLET PRESSURE TEST POINT

Next: !p1025, !f1026

DHW THERMISTOR SENSOR (MODULATION)

Next: !p1029, !f1030

CH THERMISTOR SENSOR RESISTANCE

FROM UNDERNEATH THE APPLIANCE REMOVE THE CH THERMISTOR FROM THE PIPE

Next: !p1033, !f1034

INSPECTION BYPASS

TURN CH FLOW AND RETURN ISOLATING VALVES OFF
DRAIN AND DISCHARGE BOILER

Next: !p1037, !f1038

DHW THERMISTOR SENSOR (FULL DEMAND)

REMOVE ONE YELLOW WIRE ATTACHED TO THE DHW THERMISTOR SENSOR

Next: p108, !f107

DHW THERMISTOR SENSOR (DEMAND)

REMOVE ONE YELLOW WIRE ATTACHED TO THE DHW THERMISTOR SENSOR

Next: !p1055, !f1056

CH THERMISTOR SENSOR RESISTANCE

FROM UNDERNEATH THE APPLIANCE REMOVE THE CH THERMISTOR FROM THE PIPE

Next: !p1059, !f1060

FAN VOLTAGE

ATTACH RED CROCODILE

Next: !p1065, f1066

RESISTANCE FAN AND HARNESS

DISCONNECT CONNECTOR ST1 FROM PCB

Next: p1067, f1068

RESISTANCE FAN

DISCONNECT LEADS FROM FAN ASSEMBLY (NOTE CONNECTIONS FOR REINSTATEMENT).

Next: !p1069, !f1070

AIR PRESSURE SWITCH RESISTANCE (AT REST)

DISCONNECT THE RIGHT HAND GREEN WIRE FROM THE AIR PRESSURE SWITCH

Next: !p1073, f1074

AIR PRESSURE TUBES

Next: p1075, ?1199, ?1201

APS HARNESS

REMOVE BOTH GREEN WIRES FROM THE AIR PRESSURE SWITCH
REMOVE THE ST16 PLUG FROM THE PCB CONNECTION

Next: !p1087, !f1088

REMOVE HEATING LINK

{GAINPCBACS}
DISCONNECT LINK BETWEEN LS AND LR ON ST2

Next: !p1116, !f1115

RESISTANCE MAINS FUSE

REMOVE THE FUSE FROM THE FUSED SPUR

Next: !p1120, f1122

FUSE FURTHER INVESTIGATION

Next: !p1123, !f1124

FUSE FURTHER INVESTIGATION

Next: !p1126, !f1127

FUSE FURTHER INVESTIGATION

Next: !p1129, !f1130

RESISTANCE FAN AND HARNESS TO EARTH

DISCONNECT CONNECTOR ST1 FROM PCB

Next: p1141, f1133

RESISTANCE FAN TO EARTH

DISCONNECT LEADS FROM FAN ASSEMBLY (NOTE CONNECTIONS FOR REINSTATEMENT).

Next: !p1134, !f1135

GAS VALVE 1 & 2 RESISTANCE TO EARTH

DISCONNECT THE CONNECTORS ON THE L/H SIDE OF THE GAS VALVE

Next: !p1138, !f1139

OBSERVATION COLD WATER SUPPLY

Next: p1156, !f1161

CH SENSOR & HARNESS RESISTANCE

DISCONNECT THE CONNECTOR ST16 SITUATED AT THE BOTTOM R/H SIDE OF THE PCB

Next: p767, f234

DHW MODULATION VOLTAGE

SET DHW FLOW RATE AT

Next: !p145, f144

CH SENSOR & HARNESS RESISTANCE

DISCONNECT THE CONNECTOR ST16 SITUATED AT THE BOTTOM R/H SIDE OF THE PCB

Next: !p227, f228

CH SENSOR & HARNESS RESISTANCE

DISCONNECT THE CONNECTOR ST16 SITUATED AT THE BOTTOM R/H SIDE OF THE PCB

Next: !p164, f246

CH SENSOR & HARNESS RESISTANCE

DISCONNECT THE CONNECTOR ST16 SITUATED AT THE BOTTOM R/H SIDE OF THE PCB

Next: !p262, f237

CH THERMISTOR SENSOR RESISTANCE

FROM UNDERNEATH THE APPLIANCE REMOVE THE CH THERMISTOR FROM THE PIPE

Next: !p230, !f229

CH THERMISTOR SENSOR RESISTANCE

FROM UNDERNEATH THE APPLIANCE REMOVE THE CH THERMISTOR FROM THE PIPE

Next: !p236, !f235

CH THERMISTOR SENSOR RESISTANCE

FROM UNDERNEATH THE APPLIANCE REMOVE THE CH THERMISTOR FROM THE PIPE

Next: !p239, !f238

CH THERMISTOR SENSOR RESISTANCE

FROM UNDERNEATH THE APPLIANCE REMOVE THE CH THERMISTOR FROM THE PIPE

Next: !p241, !f242

CH THERMISTOR SENSOR RESISTANCE

FROM UNDERNEATH THE APPLIANCE REMOVE THE CH THERMISTOR FROM THE PIPE

Next: !p248, !f247

GAS VALVE 3 (RESISTANCE)

REMOVE ONE OF THE BLUE WIRES ATTACHED TO THE MODULATING SOLENOID

Next: !p270, !f269

MAINS POWER SUPPLY

REMOVE BOTTOM FACIA PANEL

Next: p367, f1119

EXTERNAL CONTROLS (SEND LS)

REMOVE LOWER FACIA PANEL

Next: !p375, !f376

BURNER PRESSURE IGNITION

ATTACH A U-GAUGE TO THE GAS VALVE BURNER PRESSURE TEST POINT

Next: p403, f404

OVERHEAT AND SYSTEM PRESSURE AND HARNESS RESISTANCE

ENSURE APPLIANCE IS COOL

Next: p405, f406

INSPECTION SYSTEM PRESSURE

Next: p407, !f408

GAS VALVE 1 & 2 RESISTANCE

DISCONNECT THE CONNECTORS ON THE L/H SIDE OF THE GAS VALVE

Next: !p415, !f416

BURNER PRESSURE IGNITION

ATTACH A U-GAUGE TO THE GAS VALVE BURNER PRESSURE TEST POINT

Next: p425, f426

OVERHEAT AND SYSTEM PRESSURE AND HARNESS RESISTANCE

ENSURE APPLIANCE IS COOL

Next: p662, f428

INSPECTION SYSTEM PRESSURE

Next: p429, !f430

GAS VALVE 1 & 2 RESISTANCE

DISCONNECT THE CONNECTORS ON THE L/H SIDE OF THE GAS VALVE

Next: !p437, !f438

FAN VOLTAGE

ATTACH RED CROCODILE

Next: !p466, f494

RESISTANCE FAN AND HARNESS

DISCONNECT CONNECTOR ST1 FROM PCB

Next: p500, f496

RESISTANCE FAN

DISCONNECT LEADS FROM FAN ASSEMBLY (NOTE CONNECTIONS FOR REINSTATEMENT).

Next: !p523, !f498

TRANSFORMER RESISTANCE

REMOVE THE BACKPLATE OF THE CONTROL BOX, REMOVE THE PCB
AND THE TRANSFORMER FROM THE PCB

Next: !p535, !f536

VOLTAGE DHW FLOW SWITCH IN

{GAINPCBACS}

Next: p764, !f541

RESISTANCE FAN

DISCONNECT LEADS FROM FAN ASSEMBLY (NOTE CONNECTIONS FOR REINSTATEMENT).

Next: p555, !f599

CH SENSOR & HARNESS RESISTANCE

DISCONNECT THE CONNECTOR ST16 SITUATED AT THE BOTTOM R/H SIDE OF THE PCB

Next: !p578, f579

CH THERMISTOR SENSOR RESISTANCE

FROM UNDERNEATH THE APPLIANCE REMOVE THE CH THERMISTOR FROM THE PIPE

Next: !p580, !f581

INSPECTION BYPASS

TURN CH FLOW AND RETURN ISOLATING VALVES OFF
DRAIN AND DISCHARGE BOILER

Next: !p584, !f585

AIR PRESSURE SWITCH RESISTANCE (AT REST)

DISCONNECT THE RIGHT HAND GREEN WIRE FROM THE AIR PRESSURE SWITCH

Next: !p651, f627

AIR PRESSURE TUBES

Next: p628, ?1184, ?1186

DHW THERMISTOR SENSOR (DEMAND)

REMOVE ONE YELLOW WIRE ATTACHED TO THE DHW THERMISTOR SENSOR

Next: !p637, !f638

CH THERMISTOR SENSOR RESISTANCE

FROM UNDERNEATH THE APPLIANCE REMOVE THE CH THERMISTOR FROM THE PIPE

Next: !p641, !f642

INSPECTION SYSTEM PRESSURE

Next: p645, !f646

RESISTANCE APS WITH KIT

DISCONNECT ONE WIRE FROM THE APS

Next: p674, f683

RESISTANCE APS WITH KIT

DISCONNECT ONE WIRE FROM THE APS

Next: p688, f689

APS HARNESS

REMOVE BOTH GREEN WIRES FROM THE AIR PRESSURE SWITCH
REMOVE THE ST16 PLUG FROM THE PCB CONNECTION

Next: p738, !f751

SPARK LEADS RESISTANCE

REMOVE BOTH ENDS OF THE SPARK HARNESS, FROM THE ELECTRODE AND FROM THE TOP OF THE PCB

Next: p741, !f742

INSPECTION SYSTEM PRESSURE

Next: p745, !f746

HARNESS FLAME SENSE

REMOVE LOWER FACIA P

Next: !p758, !f759

INSPECTION SYSTEM PRESSURE

Next: p941, !f942

SPARK GENERATOR (OUTPUT)

CH POTENTIOMETER SET

Next: !p955, f956

SPARK LEADS RESISTANCE

REMOVE BOTH ENDS OF THE SPARK HARNESS, FROM THE ELECTRODE AND FROM THE TOP OF THE PCB

Next: !p957, !f958

GAS PRESSURE (INLET)

ATTACH A U-GAUGE TO THE GAS VALVE INLET PRESSURE TEST POINT

Next: !p967, !f968

HARNESS FLAME SENSE

REMOVE LOWER FACIA P

Next: !p973, !f974

GAS VALVE 1 & 2 RESISTANCE AT HARNESS

REMOVE LOWER FACIA PANEL
DISCONNECT THE CONNECTOR ST16 SITUATED AT THE BOTTOM R/H SIDE OF THE PCB

Next: p983, f984

GAS VALVE 1 & 2 RESISTANCE

DISCONNECT THE CONNECTORS ON THE L/H SIDE OF THE GAS VALVE

Next: !p985, !f986

EXTERNAL CONTROLS (RETURN LR)

REMOVE LOWER FACIA PANEL

Next: p997, f998

EXTERNAL CONTROLS (SEND LS)

REMOVE LOWER FACIA PANEL

Next: !p999, !f1000

PRESSURE BURNER MAX AND MIN

ATTACH U-GAUGE TO BURNER PRESSURE TEST POINT
SET SERVICE POTENTIOMETER TO MIN

Next: p1005, ?1007, ?1009, ?1011

DHW MODULATION

ATTACH A U-GAUGE TO THE GAS VALVE BURNER PRESSURE TEST POINT

Next: p1027, f1028

PRESSURE MIN SOLENOID DISCONNECTED

ATTACH U-GAUGE TO BU

Next: !p1023, f1024

VOLTAGE MODUREG (FULL)

REMOVE LOWER FACIA PANEL
SERVICE MODE POTENTIOMETER SET TO MAX

Next: p1015, !f1016

GAS PRESSURE (INLET)

ATTACH A U-GAUGE TO THE GAS VALVE INLET PRESSURE TEST POINT

Next: !p1013, !f1014

GAS VALVE 3 (RESISTANCE) AT HARNESS

REMOVE LOWER FACIA PANEL
DISCONNECT THE CONNECTOR ST16 SITUATED AT THE BOTTOM R/H SIDE OF THE PCB

Next: p1017, f1018

GAS PRESSURE (INLET)

ATTACH A U-GAUGE TO THE GAS VALVE INLET PRESSURE TEST POINT

Next: !p1021, !f1022

CH MODULATION

ATTACH A U-GAUGE TO

Next: p1031, f1032

DIFFERENTIAL HEAT EXCHANGER

ATTACH TEMPERATURE CLAMPS TO THE CH FLOW AND RETURN PIPES
CH POTENTIOMETER SET TO MAXIMUM

Next: p1035, f1036

INSPECTION LOCKOUT TEMPERATURE

ATTACH TEMPERATURE CLAMP TO CH FLOW PIPE
CH POTENTIOMETER SET TO MAX

Next: !p1039, ?1041, ?1043

OBSERVATION BOILER RESET FAST FLASH

ENSURE NO DEMANDS
CH TEMPERATURE SELECTOR SET TO MIN

Next: p1046, ?1047, ?1049

DHW FAN RUNS (FAULT CODE)

CH POTENTIOMETER SET TO MINIMUM

Next: p1063, f1064

DHW THERMISTOR SENSOR & HARNESS (DEMAND)

REMOVE LOWER FACIA PANEL
DISCONNECT THE CONNECTOR ST16 SITUATED AT THE BOTTOM R/H SIDE OF THE PCB

Next: p1053, f1054

INSPECTION SERVICE MODE POTENTIOMETER

{GAINPCBACS}

Next: !p1051, !f1052

CH SENSOR & HARNESS RESISTANCE

DISCONNECT THE CONNECTOR ST16 SITUATED AT THE BOTTOM R/H SIDE OF THE PCB

Next: p1057, f1058

INSPECTION ST16 PLUG AND HARNESS

DISCONNECT CONNECTOR ST16 FROM THE PCB

Next: !p1061, !f1062

GAS VALVE 3 (RESISTANCE) AT HARNESS

REMOVE LOWER FACIA PANEL
DISCONNECT THE CONNECTOR ST16 SITUATED AT THE BOTTOM R/H SIDE OF THE PCB

Next: p112, f268

RESISTANCE APS WITH KIT

DISCONNECT ONE WIRE FROM THE APS

Next: p1081, f1082

RESISTANCE APS AND HARNESS (N/C)

REMOVE LOWER FACIA PANEL
DISCONNECT THE CONNECTOR ST16 SITUATED AT THE BOTTOM R/H SIDE OF THE PCB

Next: !p1071, f1072

FLOW SENSOR (VENTURI)

REMOVE SILICONE RUBBER TUBES FROM THE VENTURI

Next: p1077, !f1078

VOLTAGE DHW FLOW SWITCH IN

{GAINPCBACS}

Next: !p110, !f109

OBSERVATION SPARKING WITH APS KIT

CONNECT THE AIR PRES

Next: p1085, f1086

AIR PRESSURE TUBES

Next: p1089, ?1194, ?1196

FLOW SENSOR (VENTURI)

REMOVE SILICONE RUBBER TUBES FROM THE VENTURI

Next: p1091, !f1092

FLUE CHECK

Next: !p1093, !f1094

VOLTAGE EXTERNAL CONTROLS (NO DEMAND)

NO DEMANDS

Next: !p1108, !f1107

OBSERVATION DISCONNECT FLOW SENSOR

DISCONNECT THE INLINE CONNECTOR TO THE FLOW SENSOR AND MAKE SAFE

Next: !p1105, !f1104

TEMPERATURE AMBIENT

Next: p1100, !f1101

CH THERMISTOR SENSOR RESISTANCE

FROM UNDERNEATH THE APPLIANCE REMOVE THE CH THERMISTOR FROM THE PIPE

Next: !p1102, !f1117

OBSERVATION ARE EXTERNAL CONTROLS FITTED

{GAINPCBACS}

Next: p1095, f1113

GAS PRESSURE (INLET)

ATTACH A U-GAUGE TO THE GAS VALVE INLET PRESSURE TEST POINT

Next: !p114, !f113

GAS VALVE 1 & 2 RESISTANCE AT HARNESS TO EARTH

REMOVE LOWER FACIA PANEL
DISCONNECT THE CONNECTOR ST16 SITUATED AT THE BOTTOM R/H SIDE OF THE PCB

Next: p1148, f1137

RESISTANCE PUMP AND HARNESS

DISCONNECT CONNECTOR ST15 FROM PCB

Next: p1136, !f1147

TRANSFORMER RESISTANCE

REMOVE THE BACKPLATE OF THE CONTROL BOX, REMOVE THE PCB
AND THE TRANSFORMER FROM THE PCB

Next: !p1151, !f1150

DHW ISOLATING VALVE

Next: p1157, !f1158

FLOW SENSOR (HALL SENSOR)

TURN OFF DHW INLET VALVE AND DRAIN DOWN THE DHW CIRCUIT

Next: !p1159, !f1160

INSPECTION HEAT EXCHANGER

GAIN ACCESS TO HEAT EXCHANGER FLUEWAYS

Next: p1164, !f1169

INSPECTION BURNER

REMOVE BURNER ASSEMBLY

Next: p1165, !f1166

INSPECTION INJECTOR

Next: p1170, !f1168

FLUE CHECK

Next: !p1171, !f1172

INSPECTION HEAT EXCHANGER

GAIN ACCESS TO HEAT EXCHANGER FLUEWAYS

Next: !p1177, !f1176

INSPECTION FAN ASSEMBLY FREE

Next: p138, !f491

INSPECTION INJECTOR

Next: !p167, !f141

FLUE CHECK

Next: p1175, !f139

CH SENSOR & HARNESS RESISTANCE

DISCONNECT THE CONNECTOR ST16 SITUATED AT THE BOTTOM R/H SIDE OF THE PCB

Next: !p157, f240

FUSE T2A

REMOVE BOTTOM FACIA PANEL
REMOVE FUSE SITUATED AT THE BOTTOM L/H SIDE OF THE PCB (MARKED T2A)

Next: p369, f1125

FUSE T1.25 A

REMOVE BOTTOM FACIA PANEL
REMOVE FUSE SITUATED AT THE BOTTOM CENTRE OF THE PCB (MARKED T1.25A)

Next: p371, f1128

EXTERNAL CONTROLS (RETURN LR)

REMOVE LOWER FACIA PANEL

Next: p532, f374

SPARK ELECTRODES GAP

Next: !p421, !f422

GAS VALVE 1 & 2 RESISTANCE AT HARNESS

REMOVE LOWER FACIA PANEL
DISCONNECT THE CONNECTOR ST16 SITUATED AT THE BOTTOM R/H SIDE OF THE PCB

Next: p413, f414

OVERHEAT THERMOSTAT (RESISTANCE)

DISCONNECT ONE OF THE ORANGE WIRES ON THE OVERHEAT THERMOSTAT

Next: p409, !f410

WATER PRESSURE SWITCH RESISTANCE

REMOVE BOTH LEADS FROM WATER PRESSURE SWITCH
ENSURE SYSTEM IS PRESSURISED CORRECTLY

Next: !p411, !f412

GAS VALVE 1 & 2 VOLTAGE

CH POTENTIOMETER SET TO MINIMUM
REMOVE THE PROGRAMMER COVER OR PROGRAMMER (IF FITTED)

Next: p417, !f418

GAS PRESSURE (INLET)

ATTACH A U-GAUGE TO THE GAS VALVE INLET PRESSURE TEST POINT

Next: !p419, !f420

SPARK ELECTRODES GAP

Next: !p443, !f444

GAS VALVE 1 & 2 RESISTANCE AT HARNESS

REMOVE LOWER FACIA PANEL
DISCONNECT THE CONNECTOR ST16 SITUATED AT THE BOTTOM R/H SIDE OF THE PCB

Next: p435, f436

OVERHEAT THERMOSTAT (RESISTANCE)

DISCONNECT ONE OF THE ORANGE WIRES ON THE OVERHEAT THERMOSTAT

Next: p431, !f432

WATER PRESSURE SWITCH RESISTANCE

REMOVE BOTH LEADS FROM WATER PRESSURE SWITCH
ENSURE SYSTEM IS PRESSURISED CORRECTLY

Next: !p433, !f434

GAS VALVE 1 & 2 VOLTAGE

CH POTENTIOMETER SET TO MINIMUM
REMOVE THE PROGRAMMER COVER OR PROGRAMMER (IF FITTED)

Next: p439, !f440

GAS PRESSURE (INLET)

ATTACH A U-GAUGE TO THE GAS VALVE INLET PRESSURE TEST POINT

Next: !p441, !f442

VOLTAGE DHW FLOW SWITCH OUT

{GAINPCBACS}

Next: p600, f539

PUMP VOLTAGE

SELECTOR SWITCH TO CH
REMOVE BOTTOM FACIA PANEL

Next: !p533, f534

INSPECTION FAN ASSEMBLY FREE

Next: !p557, !f558

INSPECTION SYSTEM PRESSURE

Next: p574, !f573

LIMPET TEST

Next: p576, !f575

CH MODULATION

ATTACH A U-GAUGE TO

Next: p582, f577

DIFFERENTIAL HEAT EXCHANGER

ATTACH TEMPERATURE CLAMPS TO THE CH FLOW AND RETURN PIPES
CH POTENTIOMETER SET TO MAXIMUM

Next: p586, f583

INSPECTION LOCKOUT TEMPERATURE

ATTACH TEMPERATURE CLAMP TO CH FLOW PIPE
CH POTENTIOMETER SET TO MAX

Next: !p594, ?595, ?597

RESISTANCE APS AND HARNESS (N/C)

REMOVE LOWER FACIA PANEL
DISCONNECT THE CONNECTOR ST16 SITUATED AT THE BOTTOM R/H SIDE OF THE PCB

Next: p634, f626

FLOW SENSOR (VENTURI)

REMOVE SILICONE RUBBER TUBES FROM THE VENTURI

Next: p630, !f631

DHW THERMISTOR SENSOR & HARNESS (DEMAND)

REMOVE LOWER FACIA PANEL
DISCONNECT THE CONNECTOR ST16 SITUATED AT THE BOTTOM R/H SIDE OF THE PCB

Next: p635, f636

CH SENSOR & HARNESS RESISTANCE

DISCONNECT THE CONNECTOR ST16 SITUATED AT THE BOTTOM R/H SIDE OF THE PCB

Next: p639, f640

RESISTANCE SAFETY CIRCUIT

REMOVE LOWER FACIA PANEL
DISCONNECT THE CONNECTOR ST16 SITUATED AT THE BOTTOM R/H SIDE OF THE PCB

Next: !p643, f644

OVERHEAT THERMOSTAT (RESISTANCE)

DISCONNECT ONE OF THE ORANGE WIRES ON THE OVERHEAT THERMOSTAT

Next: p647, !f648

WATER PRESSURE SWITCH RESISTANCE

REMOVE BOTH LEADS FROM WATER PRESSURE SWITCH
ENSURE SYSTEM IS PRESSURISED CORRECTLY

Next: !p649, !f650

OBSERVATION SPARKING WITH CASE ON

{GAINPCBACS}
DISCONNECT BOTH IGNITION LEADS FROM THE SPARK GENERATOR AND MAKE SAFE

Next: p427, f672

AIR PRESSURE TUBES

Next: p675, ?1179, ?1181

FLOW SENSOR (VENTURI)

REMOVE SILICONE RUBBER TUBES FROM THE VENTURI

Next: p677, !f678

FLUE CHECK

Next: !p686, !f680

OBSERVATION SPARKING WITH APS KIT

CONNECT THE AIR PRES

Next: p692, f723

AIR PRESSURE TUBES

Next: p706, ?1189, ?1191

FLOW SENSOR (VENTURI)

REMOVE SILICONE RUBBER TUBES FROM THE VENTURI

Next: p708, !f719

FLUE CHECK

Next: !p720, !f721

SPARK GENERATOR (OUTPUT)

CH POTENTIOMETER SET

Next: !p739, f740

RESISTANCE SAFETY CIRCUIT

REMOVE LOWER FACIA PANEL
DISCONNECT THE CONNECTOR ST16 SITUATED AT THE BOTTOM R/H SIDE OF THE PCB

Next: !p743, f744

OVERHEAT THERMOSTAT (RESISTANCE)

DISCONNECT ONE OF THE ORANGE WIRES ON THE OVERHEAT THERMOSTAT

Next: p747, !f748

WATER PRESSURE SWITCH RESISTANCE

REMOVE BOTH LEADS FROM WATER PRESSURE SWITCH
ENSURE SYSTEM IS PRESSURISED CORRECTLY

Next: !p749, !f750

INSPECTION FLAME SENSE ELECTRODE

GAIN ACCESS TO FLAME SENSE ELECTRODE

Next: p754, !f755

RESISTANCE FLAME SENSE ELECTRODE AND HARNESS

DISCONNECT CONNECTOR ST16 FROM THE PCB

Next: p756, f757

INSPECTION BURNER

REMOVE BURNER ASSEMBLY

Next: p760, !f761

INSPECTION INJECTOR

Next: !p762, !f763

FLOW SENSOR (HALL SENSOR)

TURN OFF DHW INLET VALVE AND DRAIN DOWN THE DHW CIRCUIT

Next: !p765, !f766

INSPECTION SERVICE MODE POTENTIOMETER

{GAINPCBACS}

Next: !p768, !f769

GAS PRESSURE (INLET)

ATTACH A U-GAUGE TO THE GAS VALVE INLET PRESSURE TEST POINT

Next: p1162, !f92

OBSERVATION STANDBY OPERATION

ENSURE NO DEMANDS

Next: p1109, ?1096, ?1098

RESISTANCE SAFETY CIRCUIT

REMOVE LOWER FACIA PANEL
DISCONNECT THE CONNECTOR ST16 SITUATED AT THE BOTTOM R/H SIDE OF THE PCB

Next: p939, f940

OBSERVATION BOILER RESET SLOW FLASH

Next: p947, ?949, ?951

OVERHEAT THERMOSTAT (RESISTANCE)

DISCONNECT ONE OF THE ORANGE WIRES ON THE OVERHEAT THERMOSTAT

Next: p943, !f944

WATER PRESSURE SWITCH RESISTANCE

REMOVE BOTH LEADS FROM WATER PRESSURE SWITCH
ENSURE SYSTEM IS PRESSURISED CORRECTLY

Next: !p945, !f946

INSPECTION SYSTEM PRESSURE

Next: p993, !f994

DHW SPARKING

REMOVE INNER CASING COVER
CH POTENTIOMETER SET TO MINIMUM

Next: p953, f954

DHW BURNER IGNITES (FAULT CODE)

CH POTENTIOMETER SET TO MINIMUM

Next: p959, ?961, ?963

BURNER PRESSURE IGNITION

ATTACH A U-GAUGE TO THE GAS VALVE BURNER PRESSURE TEST POINT

Next: p981, f982

GAS PRESSURE (INLET)

ATTACH A U-GAUGE TO THE GAS VALVE INLET PRESSURE TEST POINT

Next: !p979, !f980

BURNER PRESSURE IGNITION

ATTACH A U-GAUGE TO THE GAS VALVE BURNER PRESSURE TEST POINT

Next: p965, f966

INSPECTION FLAME SENSE ELECTRODE

GAIN ACCESS TO FLAME SENSE ELECTRODE

Next: p969, !f970

RESISTANCE FLAME SENSE ELECTRODE AND HARNESS

DISCONNECT CONNECTOR ST16 FROM THE PCB

Next: p971, f972

INSPECTION BURNER

REMOVE BURNER ASSEMBLY

Next: p975, !f976

INSPECTION INJECTOR

Next: !p977, !f978

SPARK ELECTRODES GAP

Next: !p991, !f992

GAS VALVE 1 & 2 VOLTAGE

CH POTENTIOMETER SET TO MINIMUM
REMOVE THE PROGRAMMER COVER OR PROGRAMMER (IF FITTED)

Next: p987, !f988

GAS PRESSURE (INLET)

ATTACH A U-GAUGE TO THE GAS VALVE INLET PRESSURE TEST POINT

Next: !p989, !f990

CH DEMAND PUMP RUNS

CH TEMPERATURE CONTR

Next: p995, f996

LIMPET TEST

Next: p1003, !f1004

PUMP VOLTAGE

SELECTOR SWITCH TO CH
REMOVE BOTTOM FACIA PANEL

Next: !p1001, !f1002

System Information

  • Total Tests: 499
  • Sequence Logic: Decoded from encrypted .seq file
  • Navigation: Dynamic based on pass/fail results
  • Source: 4731307 GW SWIFTFLOW 100 SIT Control