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 24 CDI OF

GLOBALLY REPLACED

Next: &20, *

APPLIANCE APPEARS SATISFACTORY

Next: nff

RE-IGNITE DELAY

BOILER ON/OFF SWITCH ON

Next: &nff, !f169

OVERRUN OPERATION

BOILER ON/OFF SWITCH ON

Next: &1, !f168

SPILLAGE CHECK

Next: &2, !f167

CH MODULATION

{ISOLATEMAINSPOWER}<

Next: &3, f164

EXCESSIVE SYSTEM PRESSURE RISE

BOILER ON/OFF SWITCH ON
CH TEMPERATURE SELECTOR TO MAXIMUM
ROOM THERMOSTAT (IF FITTED) CALLING

Next: &290, !f163

DHW MODULATION

{ISOLATEMAINSPOWER}<

Next: &5, f146

GAS VALVE SOUNDNESS

Next: &251, !f108

AUTOMATIC FROST PROTECTION

CH TEMPERATURE SELECTOR TO OFF
DHW TEMPERATURE SELECTOR TO MINIMUM
BOILER ON/OFF SWITCH ON

Next: &9, f105

CH BURNER IGNITES

{ISOLATEMAINSPOWER}<

Next: &10, ?95, ?97

DHW HIGH FLAME

{ISOLATEMAINSPOWER}<

Next: &11, f315

DHW LOW FLAME

{ISOLATEMAINSPOWER}<

Next: &12, f495

DHW BURNER IGNITES

{ISOLATEMAINSPOWER}
ATTACH U-GAUGE TO GAS VALVE OUTLET PRESSURE TEST POINT

Next: &201, ?50, ?52, ?54, ?56

DHW PUMP RUNS

Next: &15, f33

DHW DEMAND

{ISOLATEMAINSPOWER}
REMOVE PLASTIC COVER FROM DIVERTER VALVE MICROSWITCH

Next: &16, f30

DHW FLOW RATE

Next: &17, f462

SYSTEM CHECKS

Next: &346, !f22

WORCESTER 24 CDI OF

Next: &19, !f21

DHW BURNER ESTABLISHED (FLAME SENSE)

Next: &13, f202

DHW OPERATION

DHW TEMPERATURE SELECTOR TO MAXIMUM

Next: &7, ?252, ?254, ?256, ?327

CENTRAL HEATING OPERATION

BOILER ON/OFF SWITCH ON
ROOM THERMOSTAT (IF FITTED) CALLING

Next: &4, ?291, ?293, ?458

TYPE OF DIAGNOSTIC PROCEDURE

PLEASE SELECT FROM O

Next: &348, !f347

FAULT CODES

Next: &18, !f349

FAIL POINT A

OUTSIDE MODEL

Next: &nff, f351

FAIL POINT B

OUTSIDE MODEL

Next: &nff, f357

FAIL POINT C

OUTSIDE MODEL

Next: &nff, f363

FAIL POINT D

OUTSIDE MODEL

Next: &nff, f367

FAIL POINT E

OUTSIDE MODEL

Next: &nff, f375

FAIL POINT F

OUTSIDE MODEL

Next: &nff, f387

FAIL POINT G

OUTSIDE MODEL

Next: &nff, f393

FAIL POINT H - LINK TO DHW BURNER IGNITES

OUTSIDE MODEL

Next: &nff, !f434

FAIL POINT I

OUTSIDE MODEL

Next: &nff, f529

FAIL POINT J

OUTSIDE MODEL

Next: &nff, f442

FAIL POINT K

OUTSIDE MODEL

Next: &nff, f446

FUSE INVESTIGATION TREE

OUTSIDE MODEL

Next: &nff, f522

PRIMARY SENSOR (AUTO FROST)

KIT - THERMISTOR SENSOR - PRIMARY/DOMESTIC

Next: End

GAS VALVE SOUNDNESS

GAS VALVE

Next: End

DHW MODULATION

KIT - THERMISTOR SENSOR - PRIMARY/DOMESTIC

Next: End

EXPANSION VESSEL

EXPANSION VESSEL 10 LITRES

Next: End

PRIMARY SENSOR (CH MODULATION)

KIT - THERMISTOR SENSOR - PRIMARY/DOMESTIC

Next: End

FLUE CHECK

FLUE

Next: End

PCB (OVERRUN FUNCTION)

PCB (OVERRUN FUNCTION)

Next: End

PCB (RE-IGNITION DELAY)

PCB (RE-IGNITION DELAY)

Next: End

PRIMARY SENSOR (CH HIGH FLAME)

KIT - THERMISTOR SENSOR - PRIMARY/DOMESTIC

Next: End

GAS PRESSURE PRESENT, NO SPARKING

SPARK ELECTRODE ASSEMBLY

Next: End

SPARK ELECTRODE LEADS

HARNESS ASSEMBLY - IGNITION

Next: End

GAS PRESSURE PRESENT, NO SPARKING

HARNESS - FLUE GAS SUPERVISOR

Next: End

BURNER NOT ESTABLISHING

GAS INLET PRESSURE

Next: End

MINIMUM GAS PRESSURE

GAS VALVE

Next: End

ELECTRICAL CHECKS

ELECTRICAL CHECKS

Next: End

SYSTEM CHECKS

SYSTEM CHECKS

Next: End

DHW NOISY

HEAT EXCHANGER - GAS TO WATER

Next: End

DHW NOISY

PUMP

Next: End

DHW RUNS HOT AND COLD DHW MODULATION

KIT - THERMISTOR SENSOR - PRIMARY/DOMESTIC

Next: End

DHW HOT AND COLD

HEAT EXCHANGER - GAS TO WATER

Next: End

DHW RUNS HOT AND COLD

PUMP

Next: End

CH NOISY

PUMP

Next: End

BOILER NOISY

KIT - THERMISTOR SENSOR - PRIMARY/DOMESTIC

Next: End

CH OP NOISY

HEAT EXCHANGER - GAS TO WATER

Next: End

RADS DO NOT HEAT

ISOLATING VALVE 22MM

Next: End

RADS DO NOT HEAT

PUMP

Next: End

CH RADS COLD

DIVERTER VALVE ASSEMBLY

Next: End

DIVERTER VALVE (DIAPHRAGM)

KIT - DIAPHRAGM

Next: End

DHW NOISY

KIT - THERMISTOR SENSOR - PRIMARY/DOMESTIC

Next: End

ROOM THERMOSTAT/EXTERNAL CONTROLS

Next: End

DHW HIGH FLAME

KIT - THERMISTOR SENSOR - PRIMARY/DOMESTIC

Next: End

DHW HIGH FLAME

GAS INLET PRESSURE

Next: End

DHW COOL

PUMP

Next: End

DHW TOO COOL

HEAT EXCHANGER - GAS TO WATER

Next: End

DHW COOL RADS COOL

KIT - THERMISTOR SENSOR - PRIMARY/DOMESTIC

Next: End

DHW COOL RADS COOL

KIT - THERMISTOR SENSOR - PRIMARY/DOMESTIC

Next: End

TYPE OF DIAGNOSTIC PROCEDURE

Z REDIRECT

Next: End

FAULT CODES

Z REDIRECT

Next: End

FAIL POINT A

FUSE F1 (2 AMP)

Next: End

FAIL POINT A

Next: End

FAIL POINT B

FUSE F2 (1.25 AMP)

Next: End

FAIL POINT B

TRANSFORMER - JUNKER

Next: End

FAIL POINT C

PCB

Next: End

FAIL POINT D

Next: End

FAIL POINT D - NEON FAULTY

PCB

Next: End

FAIL POINT E

KIT - DIAPHRAGM

Next: End

FAIL POINT E

DIVERTER VALVE SWITCH ASSEMBLY

Next: End

FAIL POINT E - NEON FAULTY

PCB

Next: End

FAIL POINT F

FROST PROTECTION

Next: End

FAIL POINT F

KIT - THERMISTOR SENSOR - PRIMARY/DOMESTIC

Next: End

FAIL POINT G - NO POWER TO PUMP

PCB

Next: End

FAIL POINT G - RUNNING SLOW

PUMP

Next: End

FAIL POINT G

GAS INLET PRESSURE

Next: End

FAIL POINT G - BOSCH GV

GAS VALVE

Next: End

FAIL POINT G - DUNGS GV

GAS VALVE

Next: End

FAIL POINT G

PCB ADJUSTMENT

Next: End

FAIL POINT G

HEAT EXCHANGER - GAS TO WATER

Next: End

FAIL POINT G

PLATE HEAT EXCHANGER

Next: End

FAIL POINT G

KIT - THERMISTOR SENSOR - PRIMARY/DOMESTIC

Next: End

FAIL POINT G - NO PUMP OVERRUN

PCB

Next: End

FAIL POINT H

Z REDIRECT

Next: End

TRANSFORMER

TRANSFORMER - JUNKER

Next: End

FAIL POINT K

Z REDIRECT

Next: End

FAIL POINT J

HARNESS - FLUE GAS SUPERVISOR

Next: End

CH OPERATION SHUTTING DOWN EARLY

KIT - THERMISTOR SENSOR - PRIMARY/DOMESTIC

Next: End

DIVERTER VALVE (DHW FLOW ADJUSTER)

DIVERTER VALVE (DHW FLOW ADJUSTER)

Next: End

DHW INLET FILTER

FILTER STAINLESS STEEL - WATER INTER ALBION

Next: End

FLOW RESTRICTOR

FLOW REGULATOR

Next: End

DHW FLOW RATE

MAINS WATER SUPPLY

Next: End

DHW PUMP RUNS

DIVERTER VALVE SWITCH ASSEMBLY

Next: End

DHW BURNER ESTABLISHES - LEAD DAMAGED

PROBE - FLAME SENSE C/W LEAD

Next: End

FLAME SENSE ELECTRODE

HARNESS MAIN

Next: End

HIGH FLAME - BOSCH GV

GAS VALVE

Next: End

HIGH FLAME - DUNGS GV

GAS VALVE

Next: End

DHW LOW FLAME

GAS INLET PRESSURE

Next: End

DHW LOW FLAME - BOSCH GV

GAS VALVE

Next: End

DHW LOW FLAME - DUNGS GV

GAS VALVE

Next: End

DHW PUMP RUNS

FUSE F2 (1.25 AMP)

Next: End

DHW PUMP RUNS

FUSE F1 (2 AMP)

Next: End

DHW PUMP RUNS

MAINS FUSE

Next: End

DHW BURNER IGNITES

GAS INLET PRESSURE

Next: End

FUSE INVESTIGATION

PUMP

Next: End

FUSE INVESTIGATION - MAIN

GAS VALVE

Next: End

FUSE INVESTIGATION - MODUREG

GAS VALVE

Next: End

FAIL POINT I

KIT - THERMISTOR SENSOR - PRIMARY/DOMESTIC

Next: End

FAIL POINT I

KIT - THERMISTOR SENSOR - PRIMARY/DOMESTIC

Next: End

FAULT CODE G

THERMOSTAT - OVERHEAT

Next: End

GAS PRESSURE AND SPARKING PRESENT BUT NO IGNITION

HARNESS - FLUE GAS SUPERVISOR

Next: End

GAS PRESSURE AND SPARKING PRESENT BUT NO IGNITION

SPARK ELECTRODE ASSEMBLY

Next: End

OVERHEAT THERMOSTAT

THERMOSTAT - OVERHEAT

Next: End

NO GAS PRESENT, NO SPARKING PRESENT

KIT - THERMISTOR SENSOR - PRIMARY/DOMESTIC

Next: End

NO GAS PRESSURE, NO SPARKING PRESENT

KIT - THERMISTOR SENSOR - PRIMARY/DOMESTIC

Next: End

NO GAS PRESENT, NO SPARKING PRESENT

DIVERTER VALVE SWITCH ASSEMBLY

Next: End

NO GAS PRESSURE, NO SPARKING PRESENT

HARNESS - FLUE GAS SUPERVISOR

Next: End

MAIN GAS VALVE VOLTAGE

HARNESS - FLUE GAS SUPERVISOR

Next: End

PCB (AUTO FROST)

PCB (AUTO FROST)

Next: End

DHW MODULATION

PCB

Next: End

PRIMARY SENSOR (CH MODULATION)

PCB

Next: End

DHW BURNER IGNITES

PCB (24 VOLTS SUPPLY)

Next: End

PCB (IGNITION TRANSFORMER)

PCB (IGNITION TRANSFORMER)

Next: End

DIVERTER VALVE

DIVERTER VALVE ASSEMBLY

Next: End

DHW OPERATION NOISY

PLATE HEAT EXCHANGER

Next: End

DHW RUNS HOT AND COLDDHW MODULATION

PCB

Next: End

DHW OPERATION HOT AND COLD

PLATE HEAT EXCHANGER

Next: End

CH OP NOISY

Next: End

RADS DO NOT HEAT

Next: End

ROOM THERMOSTAT/EXTERNAL CONTROLS RESISTANCE

Next: End

DIVERTER VALVE (SPINDLE)

DIVERTER VALVE (SPINDLE)

Next: End

DHW HIGH FLAME

PCB (24 VOLTS SUPPLY)

Next: End

DHW COOL RADIATORS COOL

PLATE HEAT EXCHANGER

Next: End

DHW TOO COOL

PCB

Next: End

DHW TOO COOL RADS COLD

INJECTOR NO7 4.5MM - MAIN BURNER

Next: End

DHW TOO COOL RADS COLD

BURNER - AEROMATIC

Next: End

FAIL POINT A

PCB

Next: End

FAIL POINT B

PCB

Next: End

FAIL POINT C

Z REDIRECT

Next: End

FAIL POINT D - IGNORING CH DEMAND

PCB

Next: End

FAIL POINT D

Z REDIRECT

Next: End

FAIL POINT E

DIVERTER VALVE (SPINDLE)

Next: End

FAIL POINT E

PCB

Next: End

FAIL POINT E

Z REDIRECT

Next: End

FAIL POINT F

PCB

Next: End

FAIL POINT G

PRESSURE GAUGE

Next: End

FAIL POINT G

SYSTEM PRESSURE

Next: End

FAIL POINT G - NOT RUNNING

PUMP

Next: End

FAIL POINT G - BOSCH GV

GAS VALVE ADJUSTMENT

Next: End

FAIL POINT G - DUNGS GV

GAS VALVE ADJUSTMENT

Next: End

FAIL POINT G

Next: End

FAIL POINT G

THERMOSTAT - OVERHEAT

Next: End

FAIL POINT G - NOT SHUTTING DOWN

PCB

Next: End

NO FAULT FOUND

OVERHEAT

Next: End

FAIL POINT J

PCB

Next: End

FAIL POINT K

PCB

Next: End

DHW PUMP RUNS

PCB

Next: End

CH OPERATION SHUTTING DOWN EARLY

PCB

Next: End

PUMP

PUMP

Next: End

DHW FLOW RATE

PLATE HEAT EXCHANGER

Next: End

DHW BURNER ESTABLISHED (FLAME SENSE)

PCB

Next: End

PCB (PUMP RELAY)

PCB (PUMP RELAY)

Next: End

HIGH FLAMED - BOSCH GV

GAS VALVE ADJUSTMENT

Next: End

HIGH FLAMED - DUNGS GV

GAS VALVE ADJUSTMENT

Next: End

DHW LOW FLAME - BOSCH GV

GAS VALVE ADJUSTMENT

Next: End

DHW LOW FLAME - DUNGS GV

GAS VALVE ADJUSTMENT

Next: End

DHW PUMP RUNS - F2

Z REDIRECT

Next: End

DHW PUMP RUNS - F1

Z REDIRECT

Next: End

ON / OFF SWITCH

PCB

Next: End

DHW PUMP RUNS

Next: End

DHW PUMP RUNS - MAINS

Z REDIRECT

Next: End

SPARKING BUT NO GAS PRESSURE

GAS VALVE

Next: End

FUSE INVESTIGATION

PCB - FUSE INVESTIGATION

Next: End

FAIL POINT I - PRIMARY SENSOR

HARNESS MAIN

Next: End

FAIL POINT I

PCB

Next: End

FAIL POINT I - DHW SENSOR

HARNESS MAIN

Next: End

BURNER INJECTOR

INJECTOR NO7 4.5MM - MAIN BURNER

Next: End

PCB (LOCKOUT RESET STATUS)

PCB (LOCKOUT RESET STATUS)

Next: End

BURNER IGNITES AT HIGH FLAME

DIVERTER VALVE SWITCH ASSEMBLY

Next: End

DHW NOISY

CHARACTERISTIC TEST FROM DHW OPERATION

Next: p266

DHW RUNS HOT AND COLD

CHARACTERISTIC TEST FROM DHW OPERATION

Next: p271

DHW COOL, RADIATORS WARM

CHARACTERISTIC TEST FROM DHW OPERATION

Next: !p257

BOILER REACHES TEMPERATURE, RADS DO NOT HEAT

CHARACTERISTIC TEST FROM CENTRAL HEATING OPERATION

Next: p292

BOILER NOISY

CHARACTERISTIC TEST FROM CENTRAL HEATING OPERATION

Next: p294

DHW TOO COOL, RADIATORS COLD

CHARACTERISTIC TEST FROM DHW OPERATION

Next: p329

BURNER INJECTOR BLOCKED OR DAMAGED

CHARACTERISTIC TEST FROM INSPECTION BURNER AND INJECTOR

Next: !p343

BURNER BLOCKED OR DAMAGED

CHARACTERISTIC TEST FROM INSPECTION BURNER AND INJECTOR

Next: !p345

PRESSURE READS CORRECTLY BUT DOES NOT INCREASE

CHARACTERISTIC TEST FROM INSPECTION PRESSURE SYSTEM

Next: !p396

SYSTEM PRESSURE LOW

CHARACTERISTIC TEST FROM INSPECTION PRESSURE SYSTEM

Next: !p398

RETURNS TO OVERHEAT FAULT CODE BEFORE 82°C

CHARACTERISTIC TEST FROM OBSERVATION RUN BOILER UP TO TEMPERATURE

Next: !p426

FLOW TEMPERATURE ABOVE 88°C AND BOILER DOES NOT SHUT DOWN

CHARACTERISTIC TEST FROM OBSERVATION RUN BOILER UP TO TEMPERATURE

Next: p428

SYSTEM BEGINS TO HEAT BUT BOILER SHUTS DOWN BEFORE REACHING TEMPERATURE

CHARACTERISTIC TEST FROM CENTRAL HEATING OPERATION

Next: p459

GAS PRESSURE PRESENT, NO SPARKING

CHARACTERISTIC TEST FROM DHW BURNER IGNITES

Next: p187

GAS PRESSURE AND SPARKING PRESENT BUT NO IGNITION

CHARACTERISTIC TEST FROM DHW BURNER IGNITES

Next: p53

NO GAS PRESSURE, NO SPARKING PRESENT

CHARACTERISTIC TEST FROM DHW BURNER IGNITES

Next: p55

SPARKING BUT NO GAS PRESSURE

CHARACTERISTIC TEST FROM DHW BURNER IGNITES

Next: p57

BURNER IGNITES AT HIGH FLAME

CHARACTERISTIC TEST FROM CH BURNER IGNITES

Next: !p96

BURNER DOES NOT IGNITE OR IGNITES BUT DOES NOT RAMP UP

CHARACTERISTIC TEST FROM CH BURNER IGNITES

Next: p98

13/05/2019 14:23:24 1905_1_50_1 01/07/2019 10:09:30

10/06/2019 15:43:03

Next: End

PRIMARY SENSOR (AUTO FROST)

{ISOLATEMAINSPOWER}
DISCONNECT RED LEADS FROM SENSOR

Next: !p107, !f106

DHW SENSOR MODULATION RESISTANCE

{ISOLATEMAINSPOWER}
DISCONNECT YELLOW WIRES FROM DHW SENSOR

Next: !p148, !f147

PRIMARY SENSOR (CH MODULATION)

CH TEMPERATURE SELECTOR TO MAXIMUM

Next: !p166, !f165

PRESSURE GAS INLET

{ISOLATEMAINSPOWER}<

Next: p203, !f204

DHW SENSOR MODULATION RESISTANCE

{ISOLATEMAINSPOWER}
DISCONNECT YELLOW WIRES FROM DHW SENSOR

Next: !p275, !f276

DIVERTER VALVE DIAPHRAGM

{ISOLATEMAINSPOWER}
WATER OFF
DRAIN AND DISCHARGE BOILER

Next: !p32, !f31

PRESSURE GAS INLET

{ISOLATEMAINSPOWER}<

Next: p321, !f326

DHW SENSOR (HIGH FLAME)

{ISOLATEMAINSPOWER}
DISCONNECT YELLOW WIRES FROM DHW SENSOR
ENSURE DHW IS COOL

Next: !p324, !f325

ON/OFF SWITCH VOLTAGE (OUTPUT)

BOILER ON/OFF SWITCH ON

Next: p35, f507

DIFFERENTIAL PRIMARY HEAT EXCHANGER

{ISOLATEMAINSPOWER}
ATTACH TEMPERATURE CLAMPS TO PRIMARY FLOW AND RETURN AS INDICATED

Next: !p334, !f335

FUSE F1 (2 AMP) (FAULT CODE)

{ISOLATEMAINSPOWER}
REMOVE FUSE F1 FROM PCB

Next: p352, !f353

FUSE F2 (1.25 AMP) (FAULT CODE)

{ISOLATEMAINSPOWER}
REMOVE FUSE F2 FROM PCB

Next: p358, !f359

INFORMATION FAIL POINT C

Next: !p364, !f365

OBSERVATION DOES BOILER RESPOND TO CH DEMAND

Next: p368, f369

ROOM THERMOSTAT/EXTERNAL CONTROLS RESISTANCE

{ISOLATEMAINSPOWER}
ROOM THERMOSTAT (IF FITTED) CALLING

Next: !p370, !f371

OBSERVATION DOES BOILER RESPOND TO DHW DEMAND

Next: p376, f377

DHW DEMAND

{ISOLATEMAINSPOWER}
REMOVE PLASTIC COVER FROM DIVERTER VALVE MICROSWITCH

Next: p378, f379

DIVERTER VALVE DIAPHRAGM

{ISOLATEMAINSPOWER}
WATER OFF
DRAIN AND DISCHARGE BOILER

Next: !p380, !f381

TEMPERATURE AMBIENT

{ISOLATEMAINSPOWER}

Next: p388, !f389

INSPECTION PRESSURE SYSTEM

Next: p538, ?395, ?397

FUSE F2 (1.25 AMP)

{ISOLATEMAINSPOWER}
REMOVE FUSE F2 FROM PCB

Next: p43, f504

PUMP VOLTAGE

{ISOLATEMAINSPOWER}

Next: !p401, !f402

PRESSURE GAS INLET

{ISOLATEMAINSPOWER}<

Next: p407, !f408

ADJUSTMENT PRESSURE MAX AND MIN (BOSCH)

{ISOLATEMAINSPOWER}<

Next: !p411, !f412

DIFFERENTIAL PLATE HEAT EX

{ISOLATEMAINSPOWER}
ATTACH TEMPERATURE CLAMPS TO PRIMARY FLOW AND RETURN AS INDICATED

Next: !p419, !f420

FLUE SPILLAGE SENSOR (FAULT CODE)

{ISOLATEMAINSPOWER}<

Next: !p443, !f449

INFORMATION FAIL POINT K

{ISOLATEMAINSPOWER}<

Next: !p447, !f448

DIVERTER VALVE MICROSWITCH RESISTANCE

{ISOLATEMAINSPOWER}
DISCONNECT PLUG CONNECTOR (MARKED ST16) FROM PCB

Next: !p49, !f48

OBSERVATION COLD MAINS FLOW RATE

Next: p470, !f477

ADJUSTMENT PRESSURE MAX AND MIN (BOSCH)

{ISOLATEMAINSPOWER}<

Next: !p491, !f492

PRESSURE GAS INLET

{ISOLATEMAINSPOWER}<

Next: p496, !f497

ADJUSTMENT PRESSURE MAX AND MIN (BOSCH)

{ISOLATEMAINSPOWER}<

Next: !p500, !f501

FUSE FURTHER INVESTIGATION

Next: !p505, !f506

FUSE F1 (2 AMP)

{ISOLATEMAINSPOWER}
REMOVE FUSE F1 FROM PCB

Next: p508, f509

FUSE FURTHER INVESTIGATION

Next: !p510, !f511

RESISTANCE MAINS FUSE

{ISOLATEMAINSPOWER}
REMOVE THE FUSE FROM THE FUSED SPUR

Next: !p514, f515

FUSE FURTHER INVESTIGATION

Next: !p516, !f517

RESISTANCE PUMP AND HARNESS (FUSE INVESTIGATION)

{ISOLATEMAINSPOWER}
DISCONNECT PLUG ST15 FROM THE PCB

Next: p523, !f524

RESISTANCE PRIMARY SENSOR AT PCB (FAULT CODE)

{ISOLATEMAINSPOWER}
DISCONNECT PLUG CONNECTOR (MARKED ST16) FROM PCB

Next: p530, f531

PRIMARY SENSOR FAULT CODE

{ISOLATEMAINSPOWER}
REMOVE RED WIRES FROM CH TEMPERATURE SENSOR

Next: !p532, !f533

DHW SENSOR (CALLING)

{ISOLATEMAINSPOWER}
DISCONNECT YELLOW WIRES FROM DHW SENSOR
ENSURE DHW IS COOL

Next: !p536, !f537

FLUE SPILLAGE SENSOR

{ISOLATEMAINSPOWER}<

Next: !p179, !f80

SPARK ELECTRODES

{ISOLATEMAINSPOWER}

Next: p191, !f189

SPARK ELECTRODE LEADS

{ISOLATEMAINSPOWER}
REMOVE SPARK ELECTRODE LEADS FROM ELECTRODES AND PCB

Next: p194, !f196

FLUE SPILLAGE SENSOR

{ISOLATEMAINSPOWER}<

Next: !p199, !f200

PRESSURE GAS IGNITION

{ISOLATEMAINSPOWER}<

Next: p478, !f206

PUMP LIMPET TEST

Next: p307, !f270

CH OPERATION

BOILER ON/OFF SWITCH ON
ROOM THERMOSTAT (IF FITTED) CALLING

Next: !p268, !f269

PUMP LIMPET TEST

Next: p272, !f279

DHW MODULATION

{ISOLATEMAINSPOWER}<

Next: p273, f274

TEMPERATURE DIFFERENTIAL CH

{ISOLATEMAINSPOWER}<

Next: !p277, !f278

INSPECTION ISOLATION VALVES FLOW AND RETURN

{ISOLATEMAINSPOWER}

Next: p301, !f302

PUMP LIMPET TEST

Next: p295, !f296

RESISTANCE PRIMARY SENSOR

{ISOLATEMAINSPOWER}
REMOVE YELLOW WIRES FROM DHW SENSOR

Next: p297, !f298

TEMPERATURE DIFFERENTIAL CH

{ISOLATEMAINSPOWER}<

Next: !p299, !f300

PUMP LIMPET TEST

Next: p303, !f304

CH DIVERTER CHECK

ENSURE SECONDARY HEA

Next: !p305, !f306

RESISTANCE DHW SENSOR

{ISOLATEMAINSPOWER}
REMOVE YELLOW WIRES FROM DHW SENSOR

Next: p267, !f311

ROOM THERMOSTAT/EXTERNAL CONTROLS RESISTANCE

{ISOLATEMAINSPOWER}
ROOM THERMOSTAT (IF FITTED) CALLING

Next: !p313, !f314

FULL VOLTAGE MODULATING SOLENOID

REMOVE CONNECTOR (BL

Next: p488, f323

PUMP LIMPET TEST

Next: p330, !f331

DIFFERENTIAL PLATE HEAT EX

{ISOLATEMAINSPOWER}
ATTACH TEMPERATURE CLAMPS TO PRIMARY FLOW AND RETURN AS INDICATED

Next: p332, f333

RESISTANCE DHW SENSOR

{ISOLATEMAINSPOWER}
REMOVE YELLOW WIRES FROM DHW SENSOR

Next: p336, !f337

PRIMARY SENSOR (CH HIGH FLAME)

{ISOLATEMAINSPOWER}
REMOVE RED WIRES FROM CH SENSOR

Next: p338, !f339

INSPECTION BURNER AND INJECTOR

{ISOLATEMAINSPOWER}
REMOVE THE BURNER ASSEMBLY FROM THE BOILER

Next: !p340, ?342, ?344

TRANSFORMER VOLTAGE (OUTPUT)

BOILER ON/OFF SWITCH ON

Next: p41, f40

MAINS POWER

BOILER ON/OFF SWITCH ON

Next: !p354, !f355

TRANSFORMER RESISTANCE

{ISOLATEMAINSPOWER}<

Next: !p360, !f361

INFORMATION FAIL POINT D

Next: !p372, !f373

INFORMATION FAIL POINT E

Next: !p384, !f385

DIVERTER VALVE MICROSWITCH RESISTANCE

{ISOLATEMAINSPOWER}
DISCONNECT PLUG CONNECTOR (MARKED ST16) FROM PCB

Next: !p382, !f383

PRIMARY SENSOR (CH HIGH FLAME)

{ISOLATEMAINSPOWER}
REMOVE RED WIRES FROM CH SENSOR

Next: !p390, !f391

DHW PUMP RUNS

Next: p399, f400

PUMP LIMPET TEST

Next: p403, !f404

PRESSURE BURNER MAX AND MIN

{ISOLATEMAINSPOWER}<

Next: p405, f406

PRESSURE BURNER CH MODE

{ISOLATEMAINSPOWER}<

Next: p415, !f416

OBSERVATION GAS VALVE TYPE

THE GAS VALVE WILL N

Next: p409, f410

ADJUSTMENT PRESSURE MAX AND MIN (DUNGS)

{ISOLATEMAINSPOWER}<

Next: !p413, !f414

PUMP VOLTAGE

{ISOLATEMAINSPOWER}

Next: !p47, f46

DIFFERENTIAL PRIMARY HEAT EXCHANGER

{ISOLATEMAINSPOWER}
ATTACH TEMPERATURE CLAMPS TO PRIMARY FLOW AND RETURN AS INDICATED

Next: p417, f418

DIFFERENTIAL PLATE HEAT EX

{ISOLATEMAINSPOWER}
ATTACH TEMPERATURE CLAMPS TO PRIMARY FLOW AND RETURN AS INDICATED

Next: p421, !f422

OBSERVATION RUN BOILER UP TO TEMPERATURE

{ISOLATEMAINSPOWER}<

Next: p423, ?425, ?427

OVERRUN OPERATION

BOILER ON/OFF SWITCH ON

Next: !p431, !f432

PRIMARY SENSOR (CH HIGH FLAME)

{ISOLATEMAINSPOWER}
REMOVE RED WIRES FROM CH SENSOR

Next: !p429, !f430

TRANSFORMER RESISTANCE

{ISOLATEMAINSPOWER}<

Next: !p45, !f44

PRIMARY SENSOR (CH HIGH FLAME)

{ISOLATEMAINSPOWER}
REMOVE RED WIRES FROM CH SENSOR

Next: !p460, !f461

DHW FLOW RATE ADJUSTER

{ISOLATEMAINSPOWER}

Next: p471, !f472

DHW INLET FILTER

{ISOLATEMAINSPOWER}
WATER OFF
BOILER DRAINED AND DISCHARGED

Next: p473, !f474

FLOW RESTRICTOR

{ISOLATEMAINSPOWER}
WATER OFF
BOILER DRAINED AND DISCHARGED

Next: !p475, !f476

RESISTANCE FLAME SENSE ELECTRODE

{ISOLATEMAINSPOWER}

Next: p479, !f480

RESISTANCE FLAME SENSE LEAD

{ISOLATEMAINSPOWER}<

Next: !p481, !f482

OBSERVATION GAS VALVE TYPE

THE GAS VALVE WILL N

Next: p489, f490

ADJUSTMENT PRESSURE MAX AND MIN (DUNGS)

{ISOLATEMAINSPOWER}<

Next: !p493, !f494

OBSERVATION GAS VALVE TYPE

THE GAS VALVE WILL N

Next: p498, f499

ADJUSTMENT PRESSURE MAX AND MIN (DUNGS)

{ISOLATEMAINSPOWER}<

Next: !p502, !f503

MAINS POWER

BOILER ON/OFF SWITCH ON

Next: !p512, f513

PRESSURE GAS INLET

{ISOLATEMAINSPOWER}<

Next: !p519, !f520

MAIN GAS VALVE SOLENOID RESISTANCE (FUSE INVESTIGATION)

{ISOLATEMAINSPOWER}
DISCONNECT PLUG CONNECTOR (MARKED ST16) FROM PCB

Next: p525, !f526

RESISTANCE GAS VALVE MODULATING SOLENOID (FUSE INVESTIGATION)

{ISOLATEMAINSPOWER}
DISCONNECT PLUG CONNECTOR (MARKED ST16) FROM PCB

Next: !p527, !f528

BURNER PRESSURE (GAS PRESENT)

{ISOLATEMAINSPOWER}
ATTACH A U-GAUGE TO THE OUTLET PRESSURE TEST POINT

Next: p65, !f64

RESISTANCE DHW SENSOR AT PCB

{ISOLATEMAINSPOWER}
DISCONNECT PLUG CONNECTOR (MARKED ST16) FROM PCB

Next: !p534, f535

OVERHEAT THERMOSTAT RESISTANCE - FAULT CODE

{ISOLATEMAINSPOWER}
DISCONNECT ORANGE WIRES FROM OVERHEAT THERMOSTAT
ENSURE BOILER IS COOL

Next: p394, !f574

OVERHEAT THERMOSTAT RESISTANCE

{ISOLATEMAINSPOWER}
DISCONNECT ORANGE WIRES FROM OVERHEAT THERMOSTAT

Next: p69, !f68

MAIN GAS VALVE VOLTAGE

{ISOLATEMAINSPOWER}<

Next: p518, f78

SPARK ELECTRODES

{ISOLATEMAINSPOWER}

Next: !p67, !f66

PRIMARY SENSOR (CH CALLING)

{ISOLATEMAINSPOWER}
REMOVE RED WIRES FROM CH TEMPERATURE SENSOR

Next: p71, !f70

DHW SENSOR (CALLING)

{ISOLATEMAINSPOWER}
DISCONNECT YELLOW WIRES FROM DHW SENSOR
ENSURE DHW IS COOL

Next: p73, !f72

DIVERTER VALVE MICROSWITCH (RESISTANCE)

{ISOLATEMAINSPOWER}
DISCONNECT PLUG CONNECTOR (MARKED ST16) FROM PCB

Next: p75, !f74

FLUE SPILLAGE SENSOR

{ISOLATEMAINSPOWER}<

Next: !p77, !f76

PRIMARY SENSOR (CH HIGH FLAME)

{ISOLATEMAINSPOWER}
REMOVE RED WIRES FROM CH SENSOR

Next: p312, !f185

System Information

  • Total Tests: 322
  • Sequence Logic: Decoded from encrypted .seq file
  • Navigation: Dynamic based on pass/fail results
  • Source: 4731307 GW SWIFTFLOW 100 SIT Control