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 35 CDI II LPG

GLOBALLY REPLACED

Next: &21, *

APPLIANCE APPEARS SATISFACTORY

Next: nff

RE-IGNITE DELAY

BOILER ON/OFF SWITCH ON

Next: &nff, !f177

OVERRUN OPERATION

Next: &1, !f176

CH MODULATION

ATTACH U-GAUGE TO OUTLET PRESSURE TEST POINT ON GAS VALVE
CH TEMPERATURE SELECTOR SET TO MAX

Next: &2, f173

EXCESSIVE SYSTEM PRESSURE RISE

CH TEMPERATURE SELECTOR SET TO MAX
ROOM THERMOSTAT (IF FITTED) CALLING

Next: &3, !f172

DHW MODULATION

ATTACH U-GAUGE TO OU

Next: &566, f162

AUTOMATIC FROST PROTECTION

CH TEMPERATURE SELECTOR IN OFF POSITION
DHW TEMPERATURE SELECTOR IN MIN POSITION

Next: &517, f140

GAS VALVE SOUNDNESS

Next: &8, !f184

CH BURNER IGNITES

CH TEMPERATURE SELEC

Next: &9, ?125, ?127, ?937

HIGH FLAME

ATTACH U-GAUGE TO GA

Next: &10, f214

DHW LOW FLAME

ATTACH U-GAUGE TO GA

Next: &11, f1008

DHW BURNER IGNITES

BOILER ON/OFF SWITCH ON

Next: &226, f107

DHW SPARKING

BOILER ON/OFF SWITCH ON

Next: &14, ?442, ?461

DHW FAN RUNS

BOILER ON/OFF SWITCH ON

Next: &15, ?71, ?486

DHW PUMP RUNS

Next: &16, f45

DHW DEMAND

REMOVE PLASTIC COVER FROM DIVERTER VALVE MICROSWITCH

Next: &17, f31

DHW FLOW RATE

Next: &18, f999

WORCESTER 35 CDI II LPG

G.C. NUMBER 47 311 5

Next: &720, !f22

OPERATIONAL SEQUENCE

NO LONGER USED

Next: &19, !f225

DHW BURNER ESTABLISHED (FLAME SENSE)

BOILER ON/OFF SWITCH ON

Next: &12, f227

DHW OPERATION

DHW TEMPERATURE SET TO MAX
BOILER ON/OFF SWITCH ON

Next: &6, ?518, ?520, ?522, ?524, ?526

CH OPERATION

ROOM THERMOSTAT (IF FITTED) CALLING

Next: &4, ?567, ?569, ?948

FAULT CODES

Next: &224, !f722

TYPE OF DIAGNOSTIC PROCEDURE

PLEASE SELECT FROM O

Next: &719, !f721

FAIL POINT A

Next: &nff, f724

FAIL POINT B

OUTSIDE MODEL

Next: &nff, f730

FAIL POINT C

OUTSIDE MODEL

Next: &nff, f736

FAIL POINT D

OUTSIDE MODEL

Next: &nff, f740

FAIL POINT E

OUTSIDE MODEL

Next: &nff, f751

FAIL POINT F

OUTSIDE MODEL

Next: &nff, f766

FAIL POINT G

OUTSIDE MODEL

Next: &nff, f772

FAIL POINT H - LINK TO DHW SPARKING

OUTSIDE MODEL

Next: &nff, !f838

FAIL POINT J

OUTSIDE MODEL

Next: &nff, f886

FAIL POINT I

OUTSIDE MODEL

Next: &nff, f842

FAIL POINT K

OUTSIDE MODEL

Next: &nff, f927

FUSE INVESTIGATION TREE

NOT USED

Next: &nff, f1146

DHW FLOW RATE

DHW FLOW ADJUSTER (DIVERTER VALVE ASSEMBLY)

Next: End

DHW FLOW RATE

FILTER

Next: End

DHW FLOW RATE

REGULATOR 12 L/MIN

Next: End

DHW FLOW RATE

MAINS WATER SUPPLY

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

HIGH FLAME - BOSCH GV

GAS VALVE

Next: End

HIGH FLAME - DUNGS GV

GAS VALVE

Next: End

DHW BURNER ESTABLISHES - LEAD DAMAGED

PROBE - FLAME SENSOR C/W LEAD

Next: End

FLAME SENSE ELECTRODE

HARNESS - MAIN

Next: End

DHW BURNER IGNITES

SPARK ELECTRODES

Next: End

FAIL POINT J - NO POWER TO FAN ON DHW

CONTROL BOARD ASSEMBLY

Next: End

FAIL POINT J - FAN NOT RUNNING ON DHW DEMAND

HARNESS - FAN

Next: End

FAIL POINT J - NO POWER TO FAN ON CH

CONTROL BOARD ASSEMBLY

Next: End

FAIL POINT J - FAN NOT RUNNING ON CH DEMAND

HARNESS - FAN

Next: End

FAIL POINT J - NOT SWITCHING DHW FAULT

PRESSURE SWITCH 0.55/0.35 MB - AIR

Next: End

FAIL POINT J - APS NOT SWITCHING DHW FAULT

AIR PRESSURE SWITCH TUBES

Next: End

FAIL POINT J - APS NOT SWITCHING DHW FAULT

PROBE - AIR PRESSURE SENSING (VENTURI)

Next: End

FAIL POINT J DHW FAULT

FLUE

Next: End

FAIL POINT J - DHW FAULT

FLUE RESTRICTOR

Next: End

FAIL POINT J - NOT SWITCHING CH FAULT

PRESSURE SWITCH 0.55/0.35 MB - AIR

Next: End

FAIL POINT J - APS NOT SWITCHING CH FAULT

AIR PRESSURE SWITCH TUBES

Next: End

FAIL POINT J - APS NOT SWITCHING CH FAULT

PROBE - AIR PRESSURE SENSING (VENTURI)

Next: End

FAIL POINT J - CH FAULT

FLUE RESTRICTOR

Next: End

FAIL POINT J CH FAULT

FLUE

Next: End

FAIL POINT A

KIT - FUSE 1.25A & 2A 20MM

Next: End

FAIL POINT A

MAINS FUSE

Next: End

FAIL POINT B

KIT - FUSE 1.25A & 2A 20MM

Next: End

DHW PUMP RUNS

KIT - FUSE 1.25A & 2A 20MM

Next: End

DHW PUMP RUNS

MAINS FUSE

Next: End

DHW PUMP RUNS

KIT - FUSE 1.25A & 2A 20MM

Next: End

FUSE INVESTIGATION

PUMP

Next: End

FUSE INVESTIGATION

FAN ASSEMBLY

Next: End

FUSE INVESTIGATION - GV MODUREG

HARNESS - MAIN

Next: End

FUSE INVESTIGATION - GV MAIN

HARNESS - MAIN

Next: End

FAUIL POINT J - BOTH DEMANDS

FLUE RESTRICTOR

Next: End

DHW SPARKING

FLUE RESTRICTOR

Next: End

DHW BURNER IGNITES

GAS INLET PRESSURE

Next: End

FAIL POINT J - NOT SWITCHING CH INTERMITTENT

PRESSURE SWITCH 0.55/0.35 MB - AIR

Next: End

FAIL POINT J - APS NOT SWITCHING INTERMITTENT

AIR PRESSURE SWITCH TUBES

Next: End

FAIL POINT J - COILS WRONG INTERMITTENT

FAN ASSEMBLY

Next: End

FAIL POINT J - APS NOT SWITCHING INTERMITTENT

PROBE - AIR PRESSURE SENSING (VENTURI)

Next: End

FAIL POINT J - DIRTY INTERMITTENT

FAN ASSEMBLY

Next: End

FAIL POINT J - INTERMITTENT

FLUE RESTRICTOR

Next: End

FAIL POINT J INTERMITTENT

FLUE

Next: End

FAULT CODE

THERMOSTAT - OVERHEAT

Next: End

CH BURNER IGNITES

KIT - THERMISTOR SENSOR (PRIMARY SENSOR)

Next: End

AUTOMATIC FROST PROTECTION

KIT - THERMISTOR SENSOR (PRIMARY SENSOR AUTO FROST)

Next: End

DHW MODULATION

KIT - THERMISTOR SENSOR (DHW SENSOR)

Next: End

EXCESSIVE SYSTEM PRESSURE RISE

EXPANSION VESSEL

Next: End

CH MODULATION

KIT - THERMISTOR SENSOR (PRIMARY SENSOR)

Next: End

OVERRUN OPERATION

CONTROL BOARD ASSEMBLY

Next: End

RE-IGNITE DELAY

CONTROL BOARD ASSEMBLY

Next: End

GAS VALVE SOUNDNESS

GAS VALVE

Next: End

DHW BURNER IGNITES

CONTROL BOARD ASSEMBLY

Next: End

ELECTRICAL SAFETY CHECKS

ELECTRICAL CHECKS

Next: End

SYSTEM

SYSTEM

Next: End

NOT STAYING LIT

GAS INLET PRESSURE

Next: End

DHW BURNER ESTABLISHED

GAS VALVE

Next: End

DHW PUMP RUNS

DIVERTER VALVE SWITCH ASSEMBLY

Next: End

DHW DEMAND

KIT - DIAPHRAGM

Next: End

INLET PRESSURE

GAS INLET PRESSURE

Next: End

DHW BURNER IGNITES

HARNESS - MAIN

Next: End

DHW HIGH FLAME GAS VALVE MODULATING SOLENOID

HARNESS - MAIN

Next: End

DHW HIGH FLAME

CONTROL BOARD ASSEMBLY

Next: End

DIVERTER MICROSWITCH (OPEN)

HARNESS - MAIN

Next: End

DHW SPARKING

PRESSURE SWITCH 0.55/0.35 MB - AIR

Next: End

DHW SPARKING

SPARK ELECTRODES

Next: End

DHW SPARKING

HARNESS ASSEMBLY - IGNITION

Next: End

DHW SPARKING

AIR PRESSURE SWITCH TUBES

Next: End

DHW SPARKING

PROBE - AIR PRESSURE SENSING (VENTURI)

Next: End

DHW SPARKING

FLUE

Next: End

DHW RUNS HOT THEN COLD

PUMP

Next: End

DHW RUNS HOT THEN COLD

HEAT EXCHANGER - GAS TO WATER

Next: End

DHW TOO HOT

KIT - THERMISTOR SENSOR (DHW SENSOR)

Next: End

DHW RUNS HOT COLD

KIT - THERMISTOR SENSOR (PRIMARY SENSOR)

Next: End

DHW RUNS HOT COLD

KIT - THERMISTOR SENSOR (DHW SENSOR)

Next: End

RADS DO NOT HEAT

ISOLATION VALVES

Next: End

RADS DO NOT HEAT

PUMP

Next: End

CH RADS COLD

DIVERTER VALVE ASSEMBLY

Next: End

NO FAN

HARNESS - FAN

Next: End

DHW FAN RUNS

KIT - THERMISTOR SENSOR (PRIMARY SENSOR)

Next: End

DHW FAN RUNS

KIT - THERMISTOR SENSOR (DHW SENSOR)

Next: End

DHW FAN RUNS

DIVERTER VALVE SWITCH ASSEMBLY

Next: End

DHW PUMP RUNS

TRANSFORMER

Next: End

DHW FAN RUNS DEMAND REMOVED

AIR PRESSURE SWITCH TUBES

Next: End

DHW FAN RUNS FAN RUNS DEMAND REMOVED

PROBE - AIR PRESSURE SENSING (VENTURI)

Next: End

HEAT EXCHANGER NOISY

PUMP

Next: End

HEAT EXCHANGER NOISY

HEAT EXCHANGER - GAS TO WATER

Next: End

DHW COOL

PUMP

Next: End

DHW TOO COOL

HEAT EXCHANGER - GAS TO WATER

Next: End

DHW COOL RADS COOL

KIT - THERMISTOR SENSOR (DHW SENSOR)

Next: End

DHW COOL RADS COOL

KIT - THERMISTOR SENSOR (PRIMARY SENSOR)

Next: End

CH NOISY

PUMP

Next: End

CH NOISY

KIT - THERMISTOR SENSOR (PRIMARY SENSOR)

Next: End

TYPE OF DIAGNOSTIC PROCEDURE

Z REDIRECT

Next: End

FAULT CODES

Z REDIRECT

Next: End

FAIL POINT B

TRANSFORMER

Next: End

FAIL POINT C

CONTROL BOARD ASSEMBLY

Next: End

FAIL POINT D - NEON FAULTY

CONTROL BOARD ASSEMBLY

Next: End

FAIL POINT E - NEON FAULTY

CONTROL BOARD ASSEMBLY

Next: End

FAIL POINT E

KIT - DIAPHRAGM

Next: End

FAIL POINT E

DIVERTER VALVE SWITCH ASSEMBLY

Next: End

FAIL POINT F

FROST PROTECTION

Next: End

FAIL POINT F

KIT - THERMISTOR SENSOR (PRIMARY SENSOR AUTO FROST)

Next: End

FAIL POINT G - RUNNING SLOW

PUMP

Next: End

FAIL POINT G

GAS INLET PRESSURE

Next: End

FAIL POINT G - DUNGS GV

GAS VALVE

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 SENSOR)

Next: End

FAIL POINT G - NO PUMP OVERRUN

CONTROL BOARD ASSEMBLY

Next: End

DHW FAN RUNS

AIR PRESSURE SWITCH TUBES

Next: End

FAIL POINT G - NO POWER TO PUMP

CONTROL BOARD ASSEMBLY

Next: End

FAIL POINT H

Z REDIRECT

Next: End

DHW FAN RUNS

PROBE - AIR PRESSURE SENSING (VENTURI)

Next: End

FAIL POINT I

KIT - THERMISTOR SENSOR (PRIMARY SENSOR)

Next: End

FAIL POINT I

KIT - THERMISTOR SENSOR (DHW SENSOR)

Next: End

FAIL POINT J - SHORTING APS

AIR PRESSURE SWITCH TUBES

Next: End

FAIL POINT J - SHORTING APS

PROBE - AIR PRESSURE SENSING (VENTURI)

Next: End

FAIL POINT J - FAN NOT RUNNING ON BOTH DEMANDS

HARNESS - FAN

Next: End

FAIL POINT J - NOT SWITCHING

PRESSURE SWITCH 0.55/0.35 MB - AIR

Next: End

FAIL POINT J - IGNORING APS SWITCHING

CONTROL BOARD ASSEMBLY

Next: End

FAIL POINT J - APS NOT SWITCHING

AIR PRESSURE SWITCH TUBES

Next: End

FAIL POINT J - APS NOT SWITCHING

PROBE - AIR PRESSURE SENSING (VENTURI)

Next: End

FAIL POINT J

FLUE

Next: End

FAIL POINT K

Z REDIRECT

Next: End

FAIL POINT G - BOSCH GV

GAS VALVE

Next: End

CH CUTS OUT

KIT - THERMISTOR SENSOR (PRIMARY SENSOR)

Next: End

CH IGNITES BUT CUTS OUT

CONTROL BOARD ASSEMBLY

Next: End

CH IGNITES BUT CUTS OUT

HARNESS - FAN

Next: End

CH OPERATION SHUTTING DOWN EARLY

KIT - THERMISTOR SENSOR (PRIMARY SENSOR)

Next: End

CH BURNER IGNITES

Next: End

FAIL POINT D

Next: End

DHW SPARKS 1 SECOND

THERMOSTAT - OVERHEAT

Next: End

FAIL POINT G

PCB ADJUSTMENT

Next: End

DHW FLOW RATE

PLATE HEAT EXCHANGER

Next: End

DHW LOW FLAME - BOSCH GV

GAS VALVE ADJUSTMENT

Next: End

DHW LOW FLAME - DUNGS GV

GAS VALVE ADJUSTMENT

Next: End

HIGH FLAMED - BOSCH GV

GAS VALVE ADJUSTMENT

Next: End

HIGH FLAMED - DUNGS GV

GAS VALVE ADJUSTMENT

Next: End

DHW BURNER ESTABLISHED (FLAME SENSE)

CONTROL BOARD ASSEMBLY

Next: End

DHW BURNER IGNITES

INJECTOR - MAIN BURNER

Next: End

FAIL POINT J - NOT RUNNING ON DHW

FAN ASSEMBLY

Next: End

FAIL POINT J - NOT RUNNING ON CH

FAN ASSEMBLY

Next: End

FAIL POINT J - OPEN CIRCUIT ON APS DHW FAULT

HARNESS - MAIN

Next: End

FAIL POINT J - RUNNING SLOW DHW FAULT

FAN ASSEMBLY

Next: End

FAIL POINT J - OPEN CIRCUIT ON APS CH FAULT

HARNESS - MAIN

Next: End

FAIL POINT J - RUNNING SLOW CH FAULT

FAN ASSEMBLY

Next: End

FAIL POINT A - F1

Z REDIRECT

Next: End

FAIL POINT A

Next: End

FAIL POINT A - MAINS

Z REDIRECT

Next: End

DHW PUMP RUNS - F1

Z REDIRECT

Next: End

DHW PUMP RUNS

Next: End

DHW PUMP RUNS - MAINS

Z REDIRECT

Next: End

DHW PUMP RUNS - F2

Z REDIRECT

Next: End

FAIL POINT B

Z REDIRECT

Next: End

FUSE INVESTIGATION

HARNESS - FAN

Next: End

FUSE INVESTIGATION

PCB - FUSE INVESTIGATION

Next: End

FUSE INVESTIGATION - MODUREG

GAS VALVE

Next: End

FUSE INVESTIGATION - MAIN

GAS VALVE

Next: End

FAIL POINT J - OPEN CIRCUIT ON APS INTERMITTENT

HARNESS - MAIN

Next: End

FAIL POINT J - INTERMITTENT

CONTROL BOARD ASSEMBLY

Next: End

FAULT CODE

HARNESS - MAIN

Next: End

BURNER IGNITES AT HIGH FLAME

CONTROL BOARD ASSEMBLY

Next: End

TRANSFORMER RESISTANCE

CONTROL BOARD ASSEMBLY

Next: End

AUTOMATIC FROST PROTECTION

CONTROL BOARD ASSEMBLY

Next: End

DHW MODULATION

CONTROL BOARD ASSEMBLY

Next: End

CH MODULATION

CONTROL BOARD ASSEMBLY

Next: End

DHW BURNER IGNITES

GAS VALVE

Next: End

DIVERTER MICROSWITCH NO PUMP

HARNESS - MAIN

Next: End

AIR PRESSURE SWITCH

HARNESS - MAIN

Next: End

DHW DEMAND

DIVERTER VALVE ASSEMBLY (SPINDLE)

Next: End

DHW BURNER IGNITES SOLENOID RESISTANCE

GAS VALVE

Next: End

DHW HIGH FLAME MOD SOLENOID

GAS VALVE

Next: End

CH BURNER IGNITES

DIVERTER VALVE SWITCH ASSEMBLY

Next: End

DHW SPARKING APS

HARNESS - MAIN

Next: End

DHW SPARKING

CONTROL BOARD ASSEMBLY

Next: End

DHW SPARKING

FAN ASSEMBLY

Next: End

DHW OPERATION

DIVERTER VALVE ASSEMBLY

Next: End

DHW RUNS HOT THEN COLD

PLATE HEAT EXCHANGER

Next: End

DHW TOO HOT

CONTROL BOARD ASSEMBLY

Next: End

RADS DO NOT HEAT

Next: End

PRIMARY SENSOR NO FAN

HARNESS - MAIN

Next: End

DHW SENSOR NO FAN

HARNESS - MAIN

Next: End

FAN DOES NOT RUN

CONTROL BOARD ASSEMBLY

Next: End

DIVERTER MICROSWITCH NO FAN

HARNESS - MAIN

Next: End

DHW FAN RUNS

FAN ASSEMBLY

Next: End

FAN RUNS DEMAND REMOVED

CONTROL BOARD ASSEMBLY

Next: End

AIR PRESSURE SWITCH FAN RUNS DEMAND REMOVED

HARNESS - MAIN

Next: End

DHW FAN RUNS DEMAND REMOVED

PRESSURE SWITCH 0.55/0.35 MB - AIR

Next: End

HEAT EXCHANGER NOISY

PLATE HEAT EXCHANGER

Next: End

DHW PUMP RUNS

PUMP

Next: End

DHW COOL RADIATORS COOL

PLATE HEAT EXCHANGER

Next: End

DHW TOO COOL

CONTROL BOARD ASSEMBLY

Next: End

DHW PUMP RUNS

CONTROL BOARD ASSEMBLY

Next: End

DHW TOO COOL RADS COLD

INJECTOR - MAIN BURNER

Next: End

DHW TOO COOL RADS COLD

BURNER - LPG - AEROMATIC

Next: End

CH NOISY

CONTROL BOARD ASSEMBLY

Next: End

CH NOISY

HEAT EXCHANGER - GAS TO WATER

Next: End

CH NOISY

Next: End

CH NOISY

INJECTOR - MAIN BURNER

Next: End

CH NOISY

BURNER - LPG - AEROMATIC

Next: End

FAIL POINT A

CONTROL BOARD ASSEMBLY

Next: End

FAIL POINT B

CONTROL BOARD ASSEMBLY

Next: End

FAIL POINT C

Z REDIRECT

Next: End

FAIL POINT D

Z REDIRECT

Next: End

FAIL POINT E

Z REDIRECT

Next: End

FAIL POINT E

DIVERTER VALVE ASSEMBLY (SPINDLE)

Next: End

FAIL POINT E

CONTROL BOARD ASSEMBLY

Next: End

FAIL POINT E

HARNESS - MAIN

Next: End

FAIL POINT F

CONTROL BOARD ASSEMBLY

Next: End

FAIL POINT G

PRESSURE GAUGE

Next: End

FAIL POINT G

SYSTEM PRESSURE

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

CONTROL BOARD ASSEMBLY

Next: End

NO FAULT FOUND

OVERHEAT

Next: End

FAIL POINT G - NOT RUNNING

PUMP

Next: End

ON / OFF SWITCH

CONTROL BOARD ASSEMBLY

Next: End

FAIL POINT I - CH SENSOR

HARNESS - MAIN

Next: End

FAIL POINT I

CONTROL BOARD ASSEMBLY

Next: End

FAIL POINT I - DHW SENSOR

HARNESS - MAIN

Next: End

DHW FAN RUNS

PRESSURE SWITCH 0.55/0.35 MB - AIR

Next: End

FAIL POINT J - SHORTING APS CIRCUIT

HARNESS - MAIN

Next: End

FAIL POINT J - SHORTED

PRESSURE SWITCH 0.55/0.35 MB - AIR

Next: End

FAIL POINT J - NOT RUNNING

FAN ASSEMBLY

Next: End

FAIL POINT J - NO POWER TO FAN

CONTROL BOARD ASSEMBLY

Next: End

FAIL POINT J - OPEN CIRCUIT ON APS

HARNESS - MAIN

Next: End

FAIL POINT J - RUNNING SLOW

FAN ASSEMBLY

Next: End

FAIL POINT K

CONTROL BOARD ASSEMBLY

Next: End

FAIL POINT G - BOSCH GV

GAS VALVE ADJUSTMENT

Next: End

CH CUTS OUT ON TEMP

CONTROL BOARD ASSEMBLY

Next: End

CH IGNITES BUT CUTS OUT

FAN ASSEMBLY

Next: End

CH OPERATION SHUTTING DOWN EARLY

CONTROL BOARD ASSEMBLY

Next: End

BURNER DOES NOT IGNITE OR IGNITES BUT DOES NOT RAMP UP

CONTROL BOARD ASSEMBLY

Next: End

FAIL POINT D - IGNORING CH DEMAND

CONTROL BOARD ASSEMBLY

Next: End

PCB DHW SPARKING 1 SECOND

CONTROL BOARD ASSEMBLY

Next: End

OVERHEAT DHW SPARKING 1 SECOND

HARNESS - MAIN

Next: End

DOES NOT OCCUR ON EITHER DEMAND - INTERMITTENT FAULT

CHARACTERISTIC TEST FROM OBSERVATION WHEN DOES FAULT OCCUR

Next: p1211

BURNER IGNITES AT HIGH FLAME

CHARACTERISTIC TEST FROM CH BURNER IGNITES

Next: p126

BURNER DOES NOT IGNITE OR IGNITES BUT DOES NOT RAMP UP

CHARACTERISTIC TEST FROM CH BURNER IGNITES

Next: p128

NO SPARKING PRESENT

CHARACTERISTIC TEST FROM DHW SPARKING

Next: p444

SPARKS FOR AROUND 1 SECOND THEN GOES TO LOCKOUT

CHARACTERISTIC TEST FROM DHW SPARKING

Next: p970

FAN DOES NOT RUN BUT RUNS FOR APPROX 15 SECONDS AFTER DEMAND REMOVED

CHARACTERISTIC TEST FROM DHW FAN RUNS

Next: p495

DHW OPERATION NOISY

CHARACTERISTIC TEST FROM DHW OPERATION

Next: p640

DHW COOL, RADIATORS WARM

CHARACTERISTIC TEST FROM DHW OPERATION

Next: !p521

DHW TOO COOL, RADIATORS COLD

CHARACTERISTIC TEST FROM DHW OPERATION

Next: p662

DHW TOO HOT

CHARACTERISTIC TEST FROM DHW OPERATION

Next: p525

DHW RUNS HOT THEN COLD

CHARACTERISTIC TEST FROM DHW OPERATION

Next: p527

BOILER NOISY

CHARACTERISTIC TEST FROM CH OPERATION

Next: p696

BOILER REACHES TEMPERATURE, RADS DO NOT HEAT

CHARACTERISTIC TEST FROM CH OPERATION

Next: p570

BURNER INJECTOR BLOCKED OR DAMAGED

CHARACTERISTIC TEST FROM INSPECTION BURNER AND INJECTOR

Next: !p682

BURNER BLOCKED OR DAMAGED

CHARACTERISTIC TEST FROM INSPECTION BURNER AND INJECTOR

Next: !p684

TEMPERATURE DIFFERENTIAL INCORRECT LOCAL NOISE

CHARACTERISTIC TEST FROM DIFFERENTIAL FLOW RETURN

Next: !p704

DIFFERENTIAL OK SYSTEM NOISE

CHARACTERISTIC TEST FROM DIFFERENTIAL FLOW RETURN

Next: !p706

FAN DOES NOT RUN

CHARACTERISTIC TEST FROM DHW FAN RUNS

Next: p72

BURNER INJECTOR BLOCKED OR DAMAGED

CHARACTERISTIC TEST FROM INSPECTION BURNER AND INJECTOR

Next: !p716

BURNER BLOCKED OR DAMAGED

CHARACTERISTIC TEST FROM INSPECTION BURNER AND INJECTOR

Next: !p718

PRESSURE READS CORRECTLY BUT DOES NOT INCREASE

CHARACTERISTIC TEST FROM INSPECTION PRESSURE SYSTEM

Next: !p775

SYSTEM PRESSURE LOW

CHARACTERISTIC TEST FROM INSPECTION PRESSURE SYSTEM

Next: !p777

RETURNS TO OVERHEAT FAULT CODE BEFORE 82°C

CHARACTERISTIC TEST FROM OBSERVATION RUN BOILER UP TO TEMPERATURE

Next: !p797

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

CHARACTERISTIC TEST FROM OBSERVATION RUN BOILER UP TO TEMPERATURE

Next: p799

FAULT OCCURS ON DHW DEMAND BUT NOT CH

CHARACTERISTIC TEST FROM OBSERVATION WHEN DOES FAULT OCCUR

Next: p1063

FAULT OCCURS ON CH DEMAND BUT NOT DHW

CHARACTERISTIC TEST FROM OBSERVATION WHEN DOES FAULT OCCUR

Next: p1069

BURNER IGNITES BUT THEN CUTS OUT

CHARACTERISTIC TEST FROM CH BURNER IGNITES

Next: p938

SYSTEM BEGINS TO HEAT BUT BOILER SHUTS DOWN BEFORE REACHING TEMPERATURE

CHARACTERISTIC TEST FROM CH OPERATION

Next: p949

13/05/2019 11:33:21 1905_1_50_1 01/07/2019 10:10:24

10/06/2019 15:44:47

Next: End

INLET PRESSURE

ATTACH PRESSURE GAUG

Next: p1009, !f1010

ADJUSTMENT PRESSURE MAX AND MIN (BOSCH)

ATTACH U-GAUGE TO GA

Next: !p1013, !f1014

ADJUSTMENT PRESSURE MAX AND MIN (BOSCH)

ATTACH U-GAUGE TO GA

Next: !p1027, !f1028

RESISTANCE GAS VALVE SOLENOIDS AT PCB

DISCONNECT PLUG CONNECTOR (MARKED ST16) FROM PCB

Next: p1202, f386

VOLTAGE FAN AT PCB (DHW)

GAIN ACCESS TO PCB U

Next: p1076, !f1077

VOLTAGE FAN AT PCB (CH)

GAIN ACCESS TO PCB U

Next: p1081, !f1082

PRESSURE APS SWITCHING

DISCONNECT LEADS FROM THE AIR PRESSURE SWITCH NOTING THE CONNECTIONS

Next: !p1088, !f1089

MAIN GAS VALVE VOLTAGE

REMOVE CONNECTORS (O

Next: !p178, !f196

PRESSURE APS SWITCHING

DISCONNECT LEADS FROM THE AIR PRESSURE SWITCH NOTING THE CONNECTIONS

Next: !p1105, !f1106

RESISTANCE PUMP AND HARNESS (FUSE INV)

DISCONNECT PLUG ST15 FROM THE PCB

Next: p1174, !f1175

FUSE FURTHER INVESTIGATION

Next: !p1148, !f1149

RESISTANCE MAINS FUSE

REMOVE THE FUSE FROM THE FUSED SPUR

Next: !p1151, f1152

FUSE FURTHER INVESTIGATION

Next: !p1153, !f1154

FUSE FURTHER INVESTIGATION

Next: !p1173, !f1157

FUSE FURTHER INVESTIGATION

Next: !p1159, !f1160

RESISTANCE MAINS FUSE

REMOVE THE FUSE FROM THE FUSED SPUR

Next: !p1167, f1163

FUSE FURTHER INVESTIGATION

Next: !p1168, !f1169

FUSE FURTHER INVESTIGATION

Next: !p1171, !f1172

RESISTANCE FAN (FUSE INV)

DISCONNECT LEADS FROM THE FAN

Next: !p1180, !f1181

RESISTANCE HARNESS GAS VALVE MAIN (FUSE INV)

DISCONNECT MAIN SOLE

Next: !p1190, !f1191

RESISTANCE HARNESS GAS VALVE MODUREG (FUSE INV)

DISCONNECT MODULATING SOLENOID WIRES (BLUE CONNECTOR) FROM THE GAS VALVE

Next: !p1188, !f1189

PRESSURE APS SWITCHING

DISCONNECT LEADS FROM THE AIR PRESSURE SWITCH NOTING THE CONNECTIONS

Next: !p1214, !f1215

RESISTANCE OVERHEAT THERMOSTAT AT THERMOSTAT

DISCONNECT ORANGE WIRES FROM OVERHEAT THERMOSTAT

Next: !p1266, !f1267

PRIMARY SENSOR (AUTO FROST)

DISCONNECT RED LEADS FROM SENSOR

Next: !p142, !f141

DHW SENSOR MODULATION RESISTANCE

Next: !p164, !f163

PRIMARY SENSOR (CH MODULATION)

REMOVE RED WIRES FROM CH TEMPERATURE SENSOR
ENSURE BOILER IS COOL

Next: !p175, !f174

INLET PRESSURE

ATTACH PRESSURE GAUG

Next: p410, !f395

INLET PRESSURE

ATTACH PRESSURE GAUG

Next: p228, !f229

RESISTANCE DIVERTER VALVE MICROSWITCH AT MICROSWITCH

DISCONNECT DIVERTER MICROSWITCH AND DISCONNECT LEADS

Next: !p236, !f237

RESISTANCE AIR PRESSURE SWITCH AT APS

REMOVE GREEN WIRES FROM AIR PRESSURE SWITCH

Next: !p253, f80

DIVERTER VALVE DIAPHRAGM

DRAIN AND DISCHARGE BOILER

Next: !p33, !f32

RESISTANCE HARNESS GAS VALVE SOLENOIDS

DISCONNECT MAIN SOLE

Next: !p408, !f409

RESISTANCE HARNESS GAS VALVE MODULATING SOLENOID

DISCONNECT MODULATING SOLENOID WIRES (BLUE CONNECTOR) FROM THE GAS VALVE

Next: !p433, !f421

RESISTANCE DIVERTER VALVE MICROSWITCH AT MICROSWITCH (OPEN CIRCUIT)

DISCONNECT DIVERTER MICROSWITCH AND DISCONNECT LEADS

Next: !p440, !f441

PRESSURE APS SWITCHING

DISCONNECT LEADS FROM THE AIR PRESSURE SWITCH NOTING THE CONNECTIONS

Next: !p447, !f448

ON/OFF SWITCH VOLTAGE (OUTPUT)

GAIN ACCESS TO PCB CONNECTIONS

Next: p52, f51

SPARK ELECTRODES

Next: p451, !f452

FUSE F1 (2 AMP)

REMOVE FUSE F1 FROM PCB

Next: p54, f1158

FUSE F2 (1.25 AMP)

REMOVE FUSE F2 FROM PCB

Next: p62, f1170

VOLTAGE FAN AT PCB

USE INSULATION MAT AS NECESSARY
LOOSEN CONNECTOR FOR FAN SLIGHTLY TO EXPOSE TEST PINS

Next: p616, !f617

RESISTANCE PRIMARY SENSOR AT SENSOR

REMOVE RED WIRES FROM CH TEMPERATURE SENSOR
ENSURE BOILER IS COOL

Next: !p620, !f621

RESISTANCE DHW SENSOR AT SENSOR

Next: !p624, !f625

RESISTANCE DIVERTER VALVE MICROSWITCH AT MICROSWITCH

DISCONNECT DIVERTER MICROSWITCH AND DISCONNECT LEADS

Next: !p628, !f629

RESISTANCE AIR PRESSURE SWITCH AT APS

REMOVE GREEN WIRES FROM AIR PRESSURE SWITCH

Next: !p634, f635

AIR PRESSURE SWITCH TUBES (NA)

Next: p636, !f637

RESISTANCE DIVERTER VALVE MICROSWITCH AT PCB

DISCONNECT PLUG CONNECTOR (MARKED ST16) FROM PCB

Next: !p68, f235

DIFFERENTIAL PRIMARY HEAT EXCHANGER

ATTACH TEMPERATURE CLAMPS TO PRIMARY FLOW AND RETURN AS INDICATED

Next: !p669, !f670

FUSE F1 (2 AMP) (FAULT CODE)

REMOVE FUSE F1 FROM PCB

Next: p725, f1147

FUSE F2 (1.25 AMP) (FAULT CODE)

REMOVE FUSE F2 FROM PCB

Next: p731, f1155

INFORMATION FAIL POINT C

Next: !p737, !f738

OBSERVATION DOES BOILER RESPOND TO CH DEMAND

BOILER ON/OFF SWITCH ON

Next: p741, f964

OBSERVATION DOES BOILER RESPOND TO DHW DEMAND

BOILER ON/OFF SWITCH ON

Next: p753, f756

DHW DEMAND

REMOVE PLASTIC COVER FROM DIVERTER VALVE MICROSWITCH

Next: p760, f757

DIVERTER VALVE DIAPHRAGM

DRAIN AND DISCHARGE BOILER

Next: !p758, !f759

RESISTANCE DIVERTER VALVE MICROSWITCH AT MICROSWITCH

DISCONNECT DIVERTER MICROSWITCH AND DISCONNECT LEADS

Next: !p763, !f764

TEMPERATURE AMBIENT

Next: p767, !f768

INSPECTION PRESSURE SYSTEM

Next: p1228, ?774, ?776

INLET PRESSURE

ATTACH PRESSURE GAUG

Next: p930, !f783

DIFFERENTIAL PLATE HEAT EX

ATTACH TEMPERATURE CLAMPS TO PRIMARY FLOW AND RETURN AS INDICATED

Next: !p788, !f789

AIR PRESSURE SWITCH TUBES (NA)

Next: p83, !f82

PUMP VOLTAGE

Next: !p834, !f835

RESISTANCE PRIMARY SENSOR AT PCB (FAULT CODE)

DISCONNECT PLUG CONNECTOR (MARKED ST16) FROM PCB

Next: p843, f844

RESISTANCE PRIMARY SENSOR AT SENSOR

REMOVE RED WIRES FROM CH TEMPERATURE SENSOR
ENSURE BOILER IS COOL

Next: !p845, !f846

RESISTANCE DHW SENSOR AT SENSOR

Next: !p849, !f850

OBSERVATION WHEN DOES FAULT OCCUR

CH TEMPERATURE CONTROL TO MAX

Next: p887, ?888, ?890, ?1046

RESISTANCE AIR PRESSURE SWITCH AT PCB

DISCONNECT PLUG CONNECTOR (MARKED ST16) FROM PCB

Next: p902, f903

RESISTANCE AIR PRESSURE SWITCH AT APS

REMOVE GREEN WIRES FROM AIR PRESSURE SWITCH

Next: !p904, f905

AIR PRESSURE SWITCH TUBES (NA)

Next: p906, !f907

VOLTAGE FAN AT PCB

USE INSULATION MAT AS NECESSARY
LOOSEN CONNECTOR FOR FAN SLIGHTLY TO EXPOSE TEST PINS

Next: !p912, !f913

PRESSURE APS SWITCHING

DISCONNECT LEADS FROM THE AIR PRESSURE SWITCH NOTING THE CONNECTIONS

Next: !p916, !f917

INFORMATION FAIL POINT K


FAULT CODES NOT

Next: !p928, !f929

ADJUSTMENT PRESSURE MAX AND MIN (BOSCH)

ATTACH U-GAUGE TO GA

Next: !p935, !f936

VOLTAGE FAN AT PCB (CH)

GAIN ACCESS TO PCB U

Next: p944, !f945

ROOM THERMOSTAT/EXTERNAL CONTROLS RESISTANCE

ROOM THERMOSTAT (IF FITTED) CALLING

Next: !p965, !f966

RESISTANCE OVERHEAT THERMOSTAT AT THERMOSTAT

DISCONNECT ORANGE WIRES FROM OVERHEAT THERMOSTAT

Next: !p975, !f976

OBSERVATION COLD MAINS FLOW RATE

Next: p1000, !f1007

DHW FLOW RATE ADJUSTER

Next: p1001, !f1002

DHW INLET FILTER

BOILER DRAINED AND DISCHARGED
DHW ISOLATED AND DRAINED

Next: p1003, !f1004

FLOW RESTRICTOR

BOILER DRAINED AND DISCHARGED

Next: !p1005, !f1006

OBSERVATION GAS VALVE TYPE

THE GAS VALVE WILL N

Next: p1011, f1012

ADJUSTMENT PRESSURE MAX AND MIN (DUNGS)

ATTACH U-GAUGE TO GA

Next: !p1015, !f1016

OBSERVATION GAS VALVE TYPE

THE GAS VALVE WILL N

Next: p1025, f1026

ADJUSTMENT PRESSURE MAX AND MIN (DUNGS)

ATTACH U-GAUGE TO GA

Next: !p1029, !f1030

RESISTANCE FLAME SENSE ELECTRODE

{ISOLATEMAINSPOWER}
DISCONNECT FLAME SENSE ELECTRODE LEAD
ASSEMBLY FROM CONNECTOR

Next: p1040, !f1041

RESISTANCE FLAME SENSE LEAD

{ISOLATEMAINSPOWER}<

Next: !p1042, !f1043

OBSERVATION DOES FAN RUN (DHW)

BOILER ON/OFF SWITCH ON
ENSURE NO CH DEMAND

Next: p1085, f1075

OBSERVATION DOES FAN RUN (CH)

BOILER ON/OFF SWITCH ON
ENSURE NO DHW DEMAND

Next: p1102, f1080

VOLTAGE FAN AT FAN

BOILER ON/OFF SWITCH ON

Next: !p1078, !f1079

VOLTAGE FAN AT FAN (CH)

BOILER ON/OFF SWITCH ON

Next: !p1083, !f1084

PRESSURE APS SWITCHING AT PCB

DISCONNECT PLUG CONNECTOR (MARKED ST16) FROM PCB

Next: p1090, f1087

BURNER PRESSURE (GAS PRESENT)

ATTACH U-GAUGE TO GAS VALVE OUTLET PRESSURE TEST POINT

Next: p996, f110

AIR PRESSURE SWITCH TUBES

Next: p1091, !f1092

FLUE VENTURI (AIR DETECT)

Next: p1097, !f1094

FLUE

Next: !p1095, !f1096

INSPECTION FLUE RESTRICTOR

Next: p1093, !f1101

PRESSURE APS SWITCHING AT PCB

DISCONNECT PLUG CONNECTOR (MARKED ST16) FROM PCB

Next: p1103, f1104

AIR PRESSURE SWITCH TUBES

Next: p1107, !f1108

FLUE VENTURI (AIR DETECT)

Next: p1109, !f1110

INSPECTION FLUE RESTRICTOR

Next: p1111, !f1112

FLUE

Next: !p1113, !f1114

RESISTANCE FAN AND HARNESS (FUSE INV)

DISCONNECT PLUG ST1 FROM THE PCB

Next: p1178, f1179

RESISTANCE GAS VALVE MAIN AND HARNESS (FUSE INV)

DISCONNECT PLUG CONNECTOR (MARKED ST16) FROM PCB

Next: p1185, f1182

RESISTANCE GAS VALVE MODUREG AND HARNESS (FUSE INV)

DISCONNECT PLUG CONNECTOR (MARKED ST16) FROM PCB

Next: !p1186, f1187

INSPECTION FLUE RESTRICTOR

Next: p922, !f1196

INSPECTION FLUE RESTRICTOR

Next: p457, !f1201

INLET PRESSURE

ATTACH PRESSURE GAUG

Next: p109, !f1210

PRESSURE APS SWITCHING AT PCB

DISCONNECT PLUG CONNECTOR (MARKED ST16) FROM PCB

Next: p1212, f1213

AIR PRESSURE SWITCH TUBES

Next: p1216, !f1217

RESISTANCE FAN

DISCONNECT LEADS FROM THE FAN

Next: p1218, !f1219

FLUE VENTURI (AIR DETECT)

Next: p1220, !f1221

INSPECTION FAN

Next: p1222, !f1223

INSPECTION FLUE RESTRICTOR

Next: p1224, !f1225

FLUE

Next: !p1226, !f1227

RESISTANCE OVERHEAT THERMOSTAT AT PCB - FAULT CODE

DISCONNECT PLUG CONNECTOR (MARKED ST16) FROM PCB
ENSURE BOILER IS COOL

Next: p804, f1265

RESISTANCE DIVERTER VALVE MICROSWITCH AT PCB (OPEN CIRCUIT)

DISCONNECT PLUG CONNECTOR (MARKED ST16) FROM PCB

Next: !p130, f439

PRIMARY SENSOR (HIGH FLAME)

REMOVE RED WIRES FROM CH SENSOR

Next: p961, !f131

GAS IGNITION PRESSURE

ATTACH PRESSURE GAUG

Next: p1039, !f231

RESISTANCE GAS VALVE MODULATING SOLENOID AT PCB

DISCONNECT PLUG CONNECTOR (MARKED ST16) FROM PCB

Next: p411, f419

FULL VOLTAGE MODULATING SOLENOID

REMOVE CONNECTOR (BL

Next: p1024, !f429

PRESSURE APS SWITCHING AT PCB

DISCONNECT PLUG CONNECTOR (MARKED ST16) FROM PCB

Next: p445, f446

OBSERVATION SPARKING APS PROVED

CONNECT THE AIR PRES

Next: p449, f450

AIR PRESSURE SWITCH TUBES

Next: p455, !f456

SPARK ELECTRODE LEAD CONDITION AND CONTINUITY

REMOVE THE IGNITION LEADS FROM THE ELECTRODES AND PCB

Next: !p453, !f454

FLUE VENTURI (AIR DETECT)

Next: p1197, !f458

FLUE

Next: !p459, !f460

RESISTANCE AIR PRESSURE SWITCH AT PCB

DISCONNECT PLUG CONNECTOR (MARKED ST16) FROM PCB

Next: !p632, f633

TRANSFORMER VOLTAGE (OUTPUT)

BOILER ON/OFF SWITCH ON

Next: p60, f59

RESISTANCE DHW SENSOR AT SENSOR

Next: !p536, !f562

PUMP LIMPET TEST

Next: p528, !f529

DIFFERENTIAL PRIMARY HEAT EXCHANGER

ATTACH TEMPERATURE CLAMPS TO PRIMARY FLOW AND RETURN AS INDICATED

Next: p530, !f531

RESISTANCE PRIMARY SENSOR AT SENSOR

REMOVE RED WIRES FROM CH TEMPERATURE SENSOR
ENSURE BOILER IS COOL

Next: p532, !f563

RESISTANCE DHW SENSOR AT SENSOR

Next: !p534, !f564

MAINS POWER

Next: !p836, f1161

INSPECTION ISOLATION VALVES FLOW AND RETURN

Next: p571, !f572

PUMP LIMPET TEST

Next: p573, !f574

CH DIVERTER CHECK

ENSURE SECONDARY HEA

Next: !p575, !f596

PUMP VOLTAGE

Next: !p66, f65

RESISTANCE PRIMARY SENSOR AT PCB

DISCONNECT PLUG CONNECTOR (MARKED ST16) FROM PCB

Next: p618, f619

RESISTANCE DHW SENSOR AT PCB

DISCONNECT PLUG CONNECTOR (MARKED ST16) FROM PCB

Next: p622, f623

TRANSFORMER RESISTANCE

REMOVE TRANSFORMER FROM PCB
(THIS WILL REQUIRE THE REMOVAL OF THE METAL BACK OF THE CONTROL BOX)

Next: !p138, !f63

RESISTANCE DIVERTER VALVE MICROSWITCH AT PCB

DISCONNECT PLUG CONNECTOR (MARKED ST16) FROM PCB

Next: !p626, f627

FLUE VENTURI

Next: !p638, !f639

PUMP LIMPET TEST

Next: p641, !f642

CENTRAL HEATING OPERATION

ROOM THERMOSTAT (IF FITTED) CALLING

Next: !p643, !f644

PUMP LIMPET TEST

Next: p666, !f664

DIFFERENTIAL PLATE HEAT EX

ATTACH TEMPERATURE CLAMPS TO PRIMARY FLOW AND RETURN AS INDICATED

Next: p667, f668

RESISTANCE DHW SENSOR AT SENSOR

Next: p671, !f672

RESISTANCE PRIMARY SENSOR AT SENSOR

REMOVE RED WIRES FROM CH TEMPERATURE SENSOR
ENSURE BOILER IS COOL

Next: p673, !f674

INSPECTION BURNER AND INJECTOR

{ISOLATEMAINSPOWER}
REMOVE THE BURNER ASSEMBLY FROM THE BOILER

Next: !p678, ?681, ?683

PUMP LIMPET TEST

Next: p697, !f698

RESISTANCE PRIMARY SENSOR AT SENSOR

REMOVE RED WIRES FROM CH TEMPERATURE SENSOR
ENSURE BOILER IS COOL

Next: p707, !f700

DIFFERENTIAL FLOW RETURN

CH POTENTIOMETER SET TO MAX
ATTACH TEMPERATURE CLAMPS TO FLOW AND RETURN PIPES

Next: !p701, ?703, ?705

INSPECTION BURNER AND INJECTOR

{ISOLATEMAINSPOWER}
REMOVE THE BURNER ASSEMBLY FROM THE BOILER

Next: p699, ?715, ?717

RESISTANCE AIR PRESSURE SWITCH AT PCB

DISCONNECT PLUG CONNECTOR (MARKED ST16) FROM PCB

Next: p81, f247

MAINS POWER

Next: !p727, f1150

TRANSFORMER RESISTANCE

REMOVE TRANSFORMER FROM PCB
(THIS WILL REQUIRE THE REMOVAL OF THE METAL BACK OF THE CONTROL BOX)

Next: !p733, !f734

INFORMATION FAIL POINT D

Next: !p743, !f744

INFORMATION FAIL POINT E

Next: !p754, !f755

RESISTANCE DIVERTER VALVE MICROSWITCH AT PCB

DISCONNECT PLUG CONNECTOR (MARKED ST16) FROM PCB

Next: !p761, f762

RESISTANCE PRIMARY SENSOR AT SENSOR

REMOVE RED WIRES FROM CH TEMPERATURE SENSOR
ENSURE BOILER IS COOL

Next: !p769, !f770

PUMP LIMPET TEST

Next: p778, !f779

PRESSURE BURNER MAX AND MIN

ATTACH U-GAUGE TO GA

Next: p977, f781

DIFFERENTIAL PRIMARY HEAT EXCHANGER

ATTACH TEMPERATURE CLAMPS TO PRIMARY FLOW AND RETURN AS INDICATED

Next: p786, f787

ADJUSTMENT PRESSURE MAX AND MIN (DUNGS)

ATTACH U-GAUGE TO GA

Next: !p784, !f785

DIFFERENTIAL PLATE HEAT EX

ATTACH TEMPERATURE CLAMPS TO PRIMARY FLOW AND RETURN AS INDICATED

Next: p792, !f793

OBSERVATION RUN BOILER UP TO TEMPERATURE

CH TEMPERATURE SELECTOR TO MAX
ATTACH TEMPERATURE CLAMP TO THE FLOW PIPE BENEATH THE PUMP

Next: p794, ?796, ?798

OVERRUN OPERATION

Next: !p802, !f803

RESISTANCE PRIMARY SENSOR AT SENSOR

REMOVE RED WIRES FROM CH TEMPERATURE SENSOR
ENSURE BOILER IS COOL

Next: !p800, !f801

DHW PUMP RUNS

Next: p773, f833

VOLTAGE FAN AT FAN

BOILER ON/OFF SWITCH ON

Next: !p630, f615

FLUE VENTURI

Next: !p85, !f84

RESISTANCE DHW SENSOR AT PCB

DISCONNECT PLUG CONNECTOR (MARKED ST16) FROM PCB

Next: !p847, f848

OBSERVATION DOES FAN RUN BEFORE LOCKOUT

BOILER ON/OFF SWITCH ON

Next: p900, f901

PRESSURE APS SWITCHING AT PCB

DISCONNECT PLUG CONNECTOR (MARKED ST16) FROM PCB

Next: p914, f915

VOLTAGE FAN AT FAN

BOILER ON/OFF SWITCH ON

Next: !p910, f911

FLUE VENTURI

Next: !p908, !f909

OBSERVATION SPARKING APS PROVED

CONNECT THE AIR PRES

Next: p918, !f919

AIR PRESSURE SWITCH TUBES

Next: p920, !f921

FLUE VENTURI (AIR DETECT)

Next: p1192, !f923

FLUE

Next: !p924, !f925

OBSERVATION GAS VALVE TYPE

THE GAS VALVE WILL N

Next: p782, f934

OBSERVATION FAN RUNS CH

BOILER ON/OFF SWITCH ON

Next: p939, f943

RESISTANCE PRIMARY SENSOR AT SENSOR

REMOVE RED WIRES FROM CH TEMPERATURE SENSOR
ENSURE BOILER IS COOL

Next: !p941, !f942

VOLTAGE FAN AT FAN (CH)

BOILER ON/OFF SWITCH ON

Next: !p946, !f947

RESISTANCE PRIMARY SENSOR AT SENSOR

REMOVE RED WIRES FROM CH TEMPERATURE SENSOR
ENSURE BOILER IS COOL

Next: !p950, !f951

ROOM THERMOSTAT/EXTERNAL CONTROLS RESISTANCE

ROOM THERMOSTAT (IF FITTED) CALLING

Next: !p962, !f963

RESISTANCE OVERHEAT THERMOSTAT AT PCB

DISCONNECT PLUG CONNECTOR (MARKED ST16) FROM PCB

Next: !p973, f974

PRESSURE BURNER CH MODE

CH TEMPERATURE SELEC

Next: p780, !f995

SPARK ELECTRODES

Next: !p1044, !f1045

System Information

  • Total Tests: 496
  • Sequence Logic: Decoded from encrypted .seq file
  • Navigation: Dynamic based on pass/fail results
  • Source: 4731307 GW SWIFTFLOW 100 SIT Control