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:

CASE OFF

OUTER CASE REMOVA

Next: &1045, !f2

DHW FLOW RATE

Next: &105, f96

DOES FAN RUN ON DHW DEMAND

SELECTOR SWITCH ON HOT WATER

Next: &334, f106

BURNER IGNITES AND ESTABLISHES

{SELHWCHON}

Next: &248, ?186, ?188, ?190, ?192, ?1855

OPERATION DHW

MEASURE TEMP ACROSS

Next: &2210, ?249, ?251, ?253, ?255, ?257

DOES PUMP RUN ON HW DEMAND

Next: &185, f335

OPERATION CH

{SELHWCHON}
FLOW AND RETURN VALVES FULLY OPEN
CH THERMOSTAT SET TO MAX

Next: &nff, ?358, ?360, ?362, ?368, ?422

OVERHEAT INVESTIGATION

OUT OF MODEL

Next: &nff, f438

E20 FAULT CODE

OUT OF MODEL

Next: &nff, f585

E50 FAULT CODE

OUT OF MODEL

Next: &nff, f591

E119 FAULT CODE

OUT OF MODEL

Next: &nff, f598

E125 FAULT CODE

OUT OF MODEL

Next: &nff, f628

E130 FAULT CODE

OUT OF MODEL

Next: &nff, f696

E160 FAULT CODE

OUT OF MODEL

Next: &nff, f721

FUSE FURTHER INVESTIGATION

OUT OF MODEL

Next: &nff, f806

E168 FAULT CODE

E168 FAULT CODE
T

Next: &nff, f1615

E156 FAULT CODE

Next: &nff, !f1022

POWER UP

{SELHWCHON}
ENSURE THERE ARE NO DEMANDS

Next: &1093, ?1465, ?1467

BOILER ENTERS STANDBY MODE

{SELHWCHON}
ENSURE THERE ARE NO DEMANDS

Next: &3, ?1094, ?1098, ?1368

E164 FAULT CODE

OUT OF MODEL

Next: &nff, f1176

E28 FAULT CODE

HEADER FOR E28 FAULT CODE

Next: &nff, f2160

SF OR P CALIBRATION FUNCTION

INTENTIONALLY BLANK - HEADER FOR FAULT CODE

Next: &nff, f2220

LITE DIAGNOSTIC

DIAGNOSIS RELIES ON

Next: &nff, !f2224

QUICK ACCESS DATA AND INFORMATION

THE TABLE BELOW SHOW

Next: &nff, !f2226

HEADER FOR QADAI FLOW THERMISTOR

INTENTIONALLY BLANK - HEADER FOR QADAI

Next: &nff, f2228

HEADER FOR QADAI GAS VALVE RESISTANCE

INTENTIONALLY BLANK - HEADER FOR QADAI

Next: &nff, f2236

HEADER FOR QADAI GAS VALVE VOLTAGE

INTENTIONALLY BLANK - HEADER FOR QADAI

Next: &nff, f2240

HEADER FOR QADAI SPARK GENERATOR RESISTANCE

INTENTIONALLY BLANK - HEADER FOR QADAI

Next: &nff, f2244

HEADER FOR QADAI PUMP RESISTANCE

INTENTIONALLY BLANK - HEADER FOR QADAI

Next: &nff, f2248

HEADER FOR QADAI PUMP VOLTAGE

INTENTIONALLY BLANK - HEADER FOR QADAI

Next: &nff, f2252

HEADER FOR QADAI FAN AC RESISTANCE

INTENTIONALLY BLANK - HEADER FOR QADAI

Next: &nff, f2256

HEADER FOR QADAI FAN AC VOLTAGE

INTENTIONALLY BLANK - HEADER FOR QADAI

Next: &nff, f2260

HEADER FOR QADAI DHW SENSOR

INTENTIONALLY BLANK - HEADER FOR QADAI

Next: &nff, f2268

HEADER FOR DIVERTER VALVE RESISTANCE

INTENTIONALLY BLANK - HEADER FOR QADAI

Next: &nff, f2272

TEMP LOW

SENSOR - NTC (PRIMARY)

Next: End

E156

MAINS VOLTAGE LESS THAN 180VAC

Next: End

NO MOVEMENT

FLOW REGULATOR

Next: End

NO AC VOLTAGESTANDY BY MODE

WIRING - FAN/IGNITER

Next: End

FAN SUPPLY DC

WIRING - OVERHEAT SENSOR/FLUE THERMOSTAT/FAN

Next: End

NO FAN DC

PCB

Next: End

FAN DOES NOT RUN

PCB

Next: End

NO PRESSURE E119E164

SYSTEM PRESSURE

Next: End

BLOCKED E119E164

SWITCH - PRESSURE - HEATING (WATER PRESSURE)

Next: End

NO PUMP VOLTAGE2E125E164

PCB

Next: End

E164

PUMP

Next: End

NO SIGNAL

WIRING - DHW PRIORITY / SENSOR

Next: End

STANDBY

FAN ASSEMBLY

Next: End

POOR FLOW RATE

FLOW REGULATOR

Next: End

FROST PROTECTION

SENSOR - NTC (DHW)

Next: End

MAKING FLOW SWITCH

HOT WATER TAP OR PIPEWORK

Next: End

STUCK MADE

FLOW REGULATOR

Next: End

STUCK MADE

SENSOR - HALL EFFECT

Next: End

SHORTED GIVING DEMAND

WIRING - DHW PRIORITY / SENSOR

Next: End

FROST PROTECTION

SENSOR - NTC (PRIMARY)

Next: End

CH NO DEMAND

PCB

Next: End

HW+CHFROST STANDBY MODE

PCB

Next: End

BLOWNB4 OP SEQ

FUSE 2 AMP (NEUTRAL)

Next: End

BLANK DISPLAYB4 OP SEQ

SENSOR - HALL EFFECT

Next: End

BLANK DISPLAYB4 OP SEQ

WIRING - DHW PRIORITY / SENSOR

Next: End

BLACK DISPLAYB4 OP SEQ

FAN ASSEMBLY

Next: End

LED AT POWER UPB4 OP SEQ

PCB

Next: End

ERRATIC TEMPERATURE DISPLAY

SENSOR - NTC (PRIMARY)

Next: End

FAN NOT RUNNING

WIRING - OVERHEAT SENSOR/FLUE THERMOSTAT/FAN

Next: End

NOT RESPONDING TO FAN

PCB

Next: End

FAN NOT RUNNING E160

WIRING - OVERHEAT SENSOR/FLUE THERMOSTAT/FAN

Next: End

NO AC VOLTAGESTANDY BY MODE BLANK DISPLAY

WIRING - FAN/IGNITER

Next: End

FAN NOT RUNNING BLANK DISPLAY

WIRING - OVERHEAT SENSOR/FLUE THERMOSTAT/FAN

Next: End

FAN SUPPLY DC BLANK DISPLAY

WIRING - OVERHEAT SENSOR/FLUE THERMOSTAT/FAN

Next: End

NO FAN DC BLANK DISPLAY

PCB

Next: End

STANDBY BLANK DISPLAY

FAN ASSEMBLY

Next: End

E168

PUMP

Next: End

E168

GAS VALVE

Next: End

E168

MOTOR - 3 WAY VALVE

Next: End

E168

SPARK GENERATOR

Next: End

E168 AC

FAN ASSEMBLY

Next: End

E168 DC

FAN ASSEMBLY

Next: End

FAN RUNS DHWNO SUPPLY VOLTAGEFANE168

SENSOR - NTC (PRIMARY)

Next: End

FAN RUNSNO SUPPLY VOLTAGEFANE168

DEVICE - SAFETY - FLUE

Next: End

FAN RUNS DHWNO SUPPLY VOLTAGEFANE168

THERMOSTAT - LIMIT

Next: End

NO FANNO SUPPLY VOLTAGEFANE168

SENSOR - NTC (DHW)

Next: End

NO PRESSUREE168

SYSTEM PRESSURE

Next: End

BLOCKEDE168

SWITCH - PRESSURE - HEATING (WATER PRESSURE)

Next: End

E168

ELECTRODE - IGNITION

Next: End

E168

ELECTRODE - IONISATION

Next: End

INSUFFICIENT

WATER SUPPLY

Next: End

OPERATION CH - NOISY

TAP - ISOLATION - RETURN (FILTER)

Next: End

E125 FAULT CODE

TAP - ISOLATION - RETURN (FILTER)

Next: End

COOL HW

SENSOR - NTC (DHW)

Next: End

DHW COOL RADS COOL

SENSOR - NTC (PRIMARY)

Next: End

BLOCKAGE

3 WAY VALVE ASSEMBLY

Next: End

BLOCKED

PIPE - PRESSURE SWITCH

Next: End

EXPLOSIVE IGNITIOJN

GAS INLET PRESSURE

Next: End

EXPLOSIVE IGNITION

LEAD - IGNITION ELECTRODE

Next: End

EXPLOSIVE IGNITION

CONDENSER AND DRAIN

Next: End

EXPLOSIVE IGNITION

FLUE

Next: End

EXPLOSIVE IGNITION

ELECTRODE - IGNITION

Next: End

EXPLOSIVE IGNITION

BURNER

Next: End

EXPLOSIVE IGNITION

HEAT EXCHANGER - BASIC

Next: End

EXPLOSIVE IGNITION

FAN - PRESSURE SENSING VENTURI

Next: End

EXPLOSIVE IGNITION

PIPE - PRESSURE SWITCH

Next: End

GAS VALVE DAMAGED PCB

PCB AND GAS VALVE

Next: End

BURNER DOES NOT ESTABLISH

GAS INLET PRESSURE

Next: End

FAULTY SOLENOIDS

GAS VALVE

Next: End

BLOCKEDBLOCKED

CONDENSER AND DRAIN

Next: End

SPARKING WRONG POSITION

ELECTRODE - IGNITION

Next: End

CHOKEDBLOCKED

BURNER

Next: End

BURNER DOES NOT IGNITEBLOCKED

HEAT EXCHANGER - BASIC

Next: End

BLOCKED OR RESTRICTED

FAN - PRESSURE SENSING VENTURI

Next: End

NO DROP

FAN - PRESSURE SENSING VENTURI

Next: End

NO SPARK

WIRING - FAN/IGNITER

Next: End

NO POWER TO SPARK GEN

PCB

Next: End

NO SPARKING

LEAD - IGNITION ELECTRODE AND EARTH

Next: End

CASE REMOVAL

DIRECTION CHOICE OR CONTINUE

Next: End

NO SPARKING WITH LEAD

PCB

Next: End

NOT ESTABLISHING

CONDENSER AND DRAIN

Next: End

E125

DEVICE - SAFETY - FLUE

Next: End

BURNER BAFFLES OUT

GAS INLET PRESSURE

Next: End

NO CH VOLTAGE

PCB

Next: End

BLOCKED 2

CONDENSER AND DRAIN

Next: End

DIVERTER CH

WIRING - V3V / PLUG / GAS VALVE

Next: End

OVERHEAT

TAP - ISOLATION - RETURN (FILTER)

Next: End

DIVERTER CH DHW DIFF OK

WIRING - V3V / PLUG / GAS VALVE

Next: End

OVERHEAT DHW DIFF OK

TAP - ISOLATION - RETURN (FILTER)

Next: End

BURNER BAFFLES OUT

BURNER

Next: End

DHW COOL

3 WAY VALVE ASSEMBLY

Next: End

POOR DHW

BURNER

Next: End

OPERATION DHW - DHW COOL RADS COOL - FLUEWAYS

HEAT EXCHANGER - BASIC

Next: End

NO DISPLAY

WIRING - CONNECTOR

Next: End

BURNER BAFFLES OUT

FLUE

Next: End

FAN RUNS DHWNO SUPPLY VOLTAGEFANOH

THERMOSTAT - LIMIT

Next: End

NO RESET OVERHEAT

SWITCH - SELECTOR - 4 POSITION

Next: End

FAN RUNSNO SUPPLY VOLTAGEFANE130

DEVICE - SAFETY - FLUE

Next: End

NO RESET E130

SWITCH - SELECTOR - 4 POSITION

Next: End

BURNER DOES NOT IGNITEBLOCKEDE130

HEAT EXCHANGER - BASIC

Next: End

E28

DEVICE - SAFETY - FLUE

Next: End

E130

FLUE

Next: End

NO CH SWITCH

SWITCH - SELECTOR - 4 POSITION

Next: End

NO SUPPLY

Next: End

MISSING

CABLE - INTEGRAL TIMER

Next: End

NO CH 2

PCB

Next: End

NO CH SWITCH DHW NOISY

SWITCH - SELECTOR - 4 POSITION

Next: End

MISSING DHW NOISY

CABLE - INTEGRAL TIMER

Next: End

NO CH 2 DHW NOISY

PCB

Next: End

STUCK AFTER DEMAND

FLOW REGULATOR

Next: End

E168

Next: End

BLANK FOR LITE DIAGNOSTIC

Z DIRECTION CHOICE OR CONTINUE

Next: End

BLANK FOR QADAI

Z DIRECTION CHOICE OR CONTINUE

Next: End

QADAI

SENSOR - NTC (PRIMARY)

Next: End

QADAI

GAS VALVE

Next: End

QADAI

SPARK GENERATOR

Next: End

QADAI

PUMP

Next: End

QADAI NO POWER TO PUMP

PCB

Next: End

QADAI AC

FAN ASSEMBLY

Next: End

QADAI NO POWER TO FAN AC

PCB

Next: End

QADAI

DEVICE - SAFETY - FLUE

Next: End

QADAI

SENSOR - NTC (DHW)

Next: End

QADAI

MOTOR - 3 WAY VALVE

Next: End

BURNER IGNITES BUT BAFFLES OUT

FAN - PRESSURE SENSING VENTURI

Next: End

OPEN CIRCUIT

CABLE - ELECTRODE - FLAME SENSING

Next: End

FAULTY

ELECTRODE - IONISATION

Next: End

BURNER IGNITES BUT DOES NOT ESTABLISH

FAN - PRESSURE SENSING VENTURI

Next: End

OPERATION DHW DHW RUNS HOT THEN COLD

SENSOR - NTC (DHW)

Next: End

OPERATION DHW DHW RUNS HOT THEN COLD

SENSOR - NTC (PRIMARY)

Next: End

PREHEAT SATISFACTORY3

3 WAY VALVE ASSEMBLY

Next: End

BLOCKED PREHEAT SAT3

HEAT EXCHANGER - DHW

Next: End

FAN RUNSDHW OPERATION DHW TOO HOT

SENSOR - NTC (DHW)

Next: End

FLAME BAFFLES

HEAT EXCHANGER - BASIC

Next: End

DHW HOT THEN COLD

PUMP

Next: End

BOILER NOISY

PUMP

Next: End

NO PUMP VOLTAGE

PCB

Next: End

UNDER PRESSURE

EXPANSION VESSEL

Next: End

CLOSED

FLOW AND RETURN VALVES

Next: End

RADS COOL

PUMP

Next: End

FOR TYPE DIAG PROCEDURE

DIRECTION CHOICE OR CONTINUE

Next: End

BYPASS

3 WAY VALVE ASSEMBLY

Next: End

BLOCKED

TAP - ISOLATION - RETURN (FILTER)

Next: End

NOISY BOILER

3 WAY VALVE ASSEMBLY

Next: End

BOILER NOISY

SENSOR - NTC (PRIMARY)

Next: End

F5 FAULT CODE

PUMP

Next: End

OVERHEAT

SENSOR - NTC (DHW)

Next: End

OVERHEAT

SENSOR - NTC (PRIMARY)

Next: End

LOW TEMP

GAS INLET PRESSURE

Next: End

UNABLE TO SET

GAS VALVE

Next: End

NO CH VOLTAGETEST

PCB

Next: End

DIVERTER CHTEST

WIRING - V3V / PLUG / GAS VALVE

Next: End

DIVERTOR

WIRING - V3V / PLUG / GAS VALVE

Next: End

VOLTAGE DIVERTER

PCB

Next: End

NO PUMP VOLTAGE2

PCB

Next: End

FAN RUNS DHWNO SUPPLY VOLTAGEFANE20

SENSOR - NTC (PRIMARY)

Next: End

NO FANNO SUPPLY VOLTAGEFANE50

SENSOR - NTC (DHW)

Next: End

NO PRESSURE E119

SYSTEM PRESSURE

Next: End

BLOCKED E119

SWITCH - PRESSURE - HEATING (WATER PRESSURE)

Next: End

NO PUMP VOLTAGE2E125

PCB

Next: End

E125

PUMP

Next: End

E125

SENSOR - NTC (PRIMARY)

Next: End

E125

SENSOR - NTC (DHW)

Next: End

NO RESET

SWITCH - SELECTOR - 4 POSITION

Next: End

RESRICTIONE125

HEAT EXCHANGER - DHW

Next: End

E130

CONDENSER AND DRAIN

Next: End

NOISY

CONDENSER AND DRAIN

Next: End

CHOKEDBLOCKEDE130

BURNER

Next: End

FAN RUNS DHWNO SUPPLY VOLTAGEFAN

SENSOR - NTC (PRIMARY)

Next: End

NO FANNO SUPPLY VOLTAGEFAN

SENSOR - NTC (DHW)

Next: End

NO PRESSURE

SYSTEM PRESSURE

Next: End

BLOCKED

SWITCH - PRESSURE - HEATING (WATER PRESSURE)

Next: End

FAN RUNSNO SUPPLY VOLTAGEFAN

DEVICE - SAFETY - FLUE

Next: End

FAN RUNS DHWNO SUPPLY VOLTAGEFAN

THERMOSTAT - LIMIT

Next: End

E160

WIRING - FAN/IGNITER

Next: End

E160

PCB

Next: End

E160

WIRING - OVERHEAT SENSOR/FLUE THERMOSTAT/FAN

Next: End

NO DC SUPPLY TO FANE160

PCB

Next: End

FAULT CODES

Z DIRECTION CHOICE OR CONTINUE

Next: End

FAN SIGNAL E160

FAN ASSEMBLY

Next: End

FUSE FURTHER INVESTIGATION

GAS VALVE

Next: End

DC HARNESS

FAN ASSEMBLY

Next: End

FUSE BLOWING

MOTOR - 3 WAY VALVE

Next: End

FUSE BLOWING

FAN ASSEMBLY

Next: End

POOR FLOW RATE

TAP - ISOLATION - DHW INLET

Next: End

WATER PRESSURE E119

WIRING - DHW PRIORITY / SENSOR

Next: End

LOW SYSTEM TEMP POT

PCB

Next: End

NO MOVEMENT

SENSOR - HALL EFFECT

Next: End

VOLTS TO TURBINE

PCB

Next: End

E119 FAULTE164

PCB

Next: End

WATER PRESSURE E119E164

WIRING - DHW PRIORITY / SENSOR

Next: End

F5 FAULTE125E164

PUMP

Next: End

PUMP2E125E164

WIRING - V3V / PLUG / GAS VALVE

Next: End

NO FAN SUPPLY SPEED

PCB

Next: End

DHW

FROST PROTECTION

Next: End

FIRING NO DEMAND

Next: End

NO DEMAND

KIT - ELECTRO/MECHANICAL

Next: End

FURTHER INVESTIGATION F1B4 OP SEQ

Z DIRECTION CHOICE OR CONTINUE

Next: End

FURTHER IN VESTIGATION F2FAN DOESNT RUNB4 OP SEQ

Z DIRECTION CHOICE OR CONTINUE

Next: End

FURTHER INVESTIGATION F3B4 OP SEQ

Z DIRECTION CHOICE OR CONTINUE

Next: End

BLANK DISPLAYB4 OP SEQ

WIRING - OVERHEAT SENSOR/FLUE THERMOSTAT/FAN

Next: End

ERRATIC TEMPERATURE DISPLAY

WIRING - OVERHEAT SENSOR/FLUE THERMOSTAT/FAN

Next: End

RUNNING SLOW

FAN ASSEMBLY

Next: End

VOLTAGE NO MOVEMENTSTANDY BY MODE

FAN ASSEMBLY

Next: End

E168

WIRING - V3V / PLUG / GAS VALVE

Next: End

E168 GAS VALVE

WIRING - V3V / PLUG / GAS VALVE

Next: End

DIVERTOR E168

WIRING - V3V / PLUG / GAS VALVE

Next: End

E168 IGNITER

WIRING - FAN/IGNITER

Next: End

E168 AC

WIRING - FAN/IGNITER

Next: End

E168 FAN DC

WIRING - OVERHEAT SENSOR/FLUE THERMOSTAT/FAN

Next: End

PRIMARYNO SUPPLY VOLTAGEFANE168

WIRING - OVERHEAT SENSOR/FLUE THERMOSTAT/FAN

Next: End

FLUE STATE168

WIRING - OVERHEAT SENSOR/FLUE THERMOSTAT/FAN

Next: End

OH STATE168

WIRING - OVERHEAT SENSOR/FLUE THERMOSTAT/FAN

Next: End

DHW SENSORNO SUPPLY VOLTAGEFANE168

WIRING - DHW PRIORITY / SENSOR

Next: End

WATER PRESSURE SWITCHE168

WIRING - DHW PRIORITY / SENSOR

Next: End

RESTRICTEDE125

HEAT EXCHANGER - BASIC

Next: End

OPERATION DHW HOT COLD

PCB

Next: End

BLOCKED

HEAT EXCHANGER - DHW

Next: End

OPERATION DHW - HOT COLD

HEAT EXCHANGER - BASIC

Next: End

EXPLOSIVE IGNITION

GAS VALVE

Next: End

SPARKING NO IGNITION

GAS INLET PRESSURE

Next: End

NO GV VOLTAGE

PCB

Next: End

GAS VALVE HARNESS DAMAGED PCB

PCB AND GAS VALVE HARNESS

Next: End

GV VOLTAGEPASS

WIRING - V3V / PLUG / GAS VALVE

Next: End

MECHANICALPASS

GAS VALVE

Next: End

NOT OPENING RESISTANCE OK

GAS VALVE

Next: End

EXPLOSIVE IGNITION

SPARK GENERATOR

Next: End

SPARKING OCCURS

ELECTRODE - IGNITION

Next: End

NO SPARK - RESISTANCE

SPARK GENERATOR

Next: End

NO SPARK

SPARK GENERATOR

Next: End

E125 FLUE STAT

WIRING - OVERHEAT SENSOR/FLUE THERMOSTAT/FAN

Next: End

NOT MOVING TO CH

MOTOR - 3 WAY VALVE

Next: End

1F5FAULT 2

Next: End

RESRICTION

HEAT EXCHANGER - DHW

Next: End

NOT MOVING TO CH DHW DIFF OK

MOTOR - 3 WAY VALVE

Next: End

DHW TEMP LOW

HEAT EXCHANGER - DHW

Next: End

OPERATION DHW - DHW COOL RADS COOL - WATERWAYS

HEAT EXCHANGER - BASIC

Next: End

DHW COOL RADS COOL

PCB

Next: End

NO DISPLAY

WIRING - CONNECTOR / SELECTOR SWITCH

Next: End

NO FANB4 OP SEQ

SWITCH - SELECTOR - 4 POSITION

Next: End

FLAME BAFFLING

GAS VALVE

Next: End

OH STATOH

WIRING - OVERHEAT SENSOR/FLUE THERMOSTAT/FAN

Next: End

BOILER WONT RESET

PCB

Next: End

FLUE STATE130

WIRING - OVERHEAT SENSOR/FLUE THERMOSTAT/FAN

Next: End

NO RESETE130

PCB

Next: End

E130

NO FAULT FOUND FLUE OVERHEAT

Next: End

E28

PCB

Next: End

E28

WIRING - OVERHEAT SENSOR/FLUE THERMOSTAT/FAN

Next: End

NO CH

PCB

Next: End

NO CH3

PCB

Next: End

NO SWITCH BACK

KIT - ELECTRO/MECHANICAL

Next: End

NO CH DHW NOISY

PCB

Next: End

NO CH3 DHW NOISY

PCB

Next: End

NO SWITCH BACK DHW NOISY

KIT - ELECTRO/MECHANICAL

Next: End

STUCK AFTER DEMAND

SENSOR - HALL EFFECT

Next: End

NORMAL OPERATION

CALIBRATION FUNCTION

Next: End

SENSOR TEMP FLOW

RESULT AS EXPECTED

Next: End

GAS VALVE

RESULT AS EXPECTED

Next: End

PCB POWER TO GAS VALVE

RESULT AS EXPECTED

Next: End

SPARK GENERATOR

RESULT AS EXPECTED

Next: End

PUMP

RESULT AS EXPECTED

Next: End

PCB POWER TO PUMP

RESULT AS EXPECTED

Next: End

FAN AC

RESULT AS EXPECTED

Next: End

PCB POWER TO FAN AC

RESULT AS EXPECTED

Next: End

SENSOR FLUE

RESULT AS EXPECTED

Next: End

DHW SENSOR

RESULT AS EXPECTED

Next: End

DIVERTER VALVE HEAD

RESULT AS EXPECTED

Next: End

NO RETIFICATION

PCB

Next: End

DHW NOISY KETTLING

HEAT EXCHANGER - DHW

Next: End

LETBY PREHEAT3

3 WAY VALVE ASSEMBLY

Next: End

TEMPERATURE CONTROL DHW

PCB

Next: End

VOLTAGE NOT RUNNING

PUMP

Next: End

PUMP

WIRING - V3V / PLUG / GAS VALVE

Next: End

EXPANSION CONNECTION

BLOCKAGE

Next: End

F5 FAULT

PUMP

Next: End

OVERHEAT

TEMPERATURE OVERHEAT

Next: End

EXCESSIVE TEMP

PCB

Next: End

CUTTING OFF

THERMOSTAT - LIMIT

Next: End

DHW NOISY KETTLING

HEAT EXCHANGER - BASIC

Next: End

NOT MOVING TO CHTEST

MOTOR - 3 WAY VALVE

Next: End

PREHEAT SATISFACTORY3

MOTOR - 3 WAY VALVE

Next: End

CH OPERATION NOISY

HEAT EXCHANGER - BASIC

Next: End

PUMP2

WIRING - V3V / PLUG / GAS VALVE

Next: End

PRIMARYNO SUPPLY VOLTAGEFANE20

WIRING - OVERHEAT SENSOR/FLUE THERMOSTAT/FAN

Next: End

E20

PCB

Next: End

DHW SENSORNO SUPPLY VOLTAGEFANE50

WIRING - DHW PRIORITY / SENSOR

Next: End

E50

PCB

Next: End

E119 FAULT

PCB

Next: End

F5 FAULTE125

PUMP

Next: End

PUMP2E125

WIRING - V3V / PLUG / GAS VALVE

Next: End

NO RESET

PCB

Next: End

ALL OKAY

BOILER LOCKOUT

Next: End

PRIMARYNO SUPPLY VOLTAGEFAN

WIRING - OVERHEAT SENSOR/FLUE THERMOSTAT/FAN

Next: End

DHW SENSORNO SUPPLY VOLTAGEFAN

WIRING - DHW PRIORITY / SENSOR

Next: End

WATER PRESSURE SWITCH

WIRING - DHW PRIORITY / SENSOR

Next: End

FLUE STAT

WIRING - OVERHEAT SENSOR/FLUE THERMOSTAT/FAN

Next: End

NOT RECONISING DEMAND

PCB

Next: End

OH STAT

WIRING - OVERHEAT SENSOR/FLUE THERMOSTAT/FAN

Next: End

PCB FUSE BLOWING

FUSE GONE PCB

Next: End

FUSE

WIRING - V3V / PLUG / GAS VALVE

Next: End

FUSE2

WIRING - V3V / PLUG / GAS VALVE

Next: End

FUSE

WIRING - OVERHEAT SENSOR/FLUE THERMOSTAT/FAN

Next: End

FUSE GAS VALVE

WIRING - V3V / PLUG / GAS VALVE

Next: End

FUSE

WIRING - FAN/IGNITER

Next: End

POOR FLOW RATE

HEAT EXCHANGER - DHW

Next: End

F5 FAULTE125DHW NOISY

PUMP

Next: End

PUMP2E125DHW NOISY

WIRING - V3V / PLUG / GAS VALVE

Next: End

NO VOLTAGE PRESENT

CHARACTERISTIC TEST FROM DHW FLOW SWITCH OPERATION

Next: !p109

FAN RUNS CONTINUALLY

CHARACTERISTIC TEST FROM BOILER ENTERS STANDBY MODE

Next: p1095

FAN DOES NOT RUN ON SELF CHECK

CHARACTERISTIC TEST FROM BOILER ENTERS STANDBY MODE

Next: p1099

VOLTAGE STAYS THE SAME

CHARACTERISTIC TEST FROM DHW FLOW SWITCH OPERATION

Next: p1287

DHW OR CH DEMAND LED ILLUMINATED

CHARACTERISTIC TEST FROM BOILER ENTERS STANDBY MODE

Next: p1430

DISPLAY DOES NOT ILLUMINATE

CHARACTERISTIC TEST FROM POWER UP

Next: p1469

DISPLAY ILLUMINATES BUT TEMPERATURE DISPLAYED ERRATIC

CHARACTERISTIC TEST FROM POWER UP

Next: p1516

FAN RUNS CONTINUOUSLY AT HIGH SPEED

CHARACTERISTIC TEST FROM FAN RUNS SELF CHECK

Next: p1491

FAN DOESN'T RUN

CHARACTERISTIC TEST FROM FAN RUNS SELF CHECK

Next: p1493

EXPLOSIVE OR DELAYED IGNITION

CHARACTERISTIC TEST FROM BURNER IGNITES AND ESTABLISHES

Next: p1899

SPARKING OCCURS BURNER DOES NOT IGNITE

CHARACTERISTIC TEST FROM BURNER IGNITES AND ESTABLISHES

Next: p1811

FAN RUNS SPARKING DOES NOT OCCUR

CHARACTERISTIC TEST FROM BURNER IGNITES AND ESTABLISHES

Next: p1972

BURNER IGNITES BUT BAFFLES OUT OR LIFTS OFF

CHARACTERISTIC TEST FROM BURNER IGNITES AND ESTABLISHES

Next: p191

BURNER IGNITES BUT DOES NOT ESTABLISH

CHARACTERISTIC TEST FROM BURNER IGNITES AND ESTABLISHES

Next: p193

GAS INLET PRESSURE LOW OR DROPS BELOW MINIMUM

CHARACTERISTIC TEST FROM PRESSURE GAS INLET AND DROP

Next: !p1941

GAS INLET PRESSURE OK BUT DOES NOT DROP

CHARACTERISTIC TEST FROM PRESSURE GAS INLET AND DROP

Next: p1943

VOLTAGE MISSING

CHARACTERISTIC TEST FROM VOLTAGE FROM INTEGRAL TIMER

Next: p2184

NO INTEGRAL TIMER FITTED

CHARACTERISTIC TEST FROM VOLTAGE FROM INTEGRAL TIMER

Next: p2186

VOLTAGE MISSING

CHARACTERISTIC TEST FROM VOLTAGE FROM INTEGRAL TIMER

Next: p2203

NO INTEGRAL TIMER FITTED

CHARACTERISTIC TEST FROM VOLTAGE FROM INTEGRAL TIMER

Next: p2205

DHW TOO HOT

CHARACTERISTIC TEST FROM OPERATION DHW

Next: p250

DHW COOL RADS COOL

CHARACTERISTIC TEST FROM OPERATION DHW

Next: p252

DHW COOL RADS HOT WITH NO CH DEMAND

CHARACTERISTIC TEST FROM OPERATION DHW

Next: p254

DHW NOISY KETTLING

CHARACTERISTIC TEST FROM OPERATION DHW

Next: p256

DHW RUNS HOT THEN COLD

CHARACTERISTIC TEST FROM OPERATION DHW

Next: p258

BOILER DOES NOT REACT TO CH DEMAND

CHARACTERISTIC TEST FROM CH OPERATION (FOR HEAT EX DIAG)

Next: p2191

BOILER KETTLES

CHARACTERISTIC TEST FROM CH OPERATION (FOR HEAT EX DIAG)

Next: !p536

BOILER NOISY

CHARACTERISTIC TEST FROM OPERATION CH

Next: p359

BOILER UP TO TEMP RADS COLD

CHARACTERISTIC TEST FROM OPERATION CH

Next: p361

BOILER TEMP LOW SYSTEM TEMP LOW

CHARACTERISTIC TEST FROM OPERATION CH

Next: p1014

SYSTEM PRESSURE RISE EXCESSIVE

CHARACTERISTIC TEST FROM OPERATION CH

Next: p369

BOILER DOES NOT RESPOND TO CH DEMAND

CHARACTERISTIC TEST FROM OPERATION CH

Next: p2172

BOILER TEMP GOES ABOVE 90 DEGREES AND DOESNT CUT OFF

CHARACTERISTIC TEST FROM CH TEST OVERHEAT

Next: !p512

BOILER LOCKS OUT ON OVERHEAT BEFORE REACHING 85 DEGREES

CHARACTERISTIC TEST FROM CH TEST OVERHEAT

Next: !p516

TEMP DIFFERENTIAL NOT OK LOCAL BOILING

CHARACTERISTIC TEST FROM TEMPERATURE DIFFERENTIAL FLOW RETURN (P=DIF NOK NOISY NSD)

Next: !p570

DIFFERENTIAL OK SYSTEM NOISE

CHARACTERISTIC TEST FROM TEMPERATURE DIFFERENTIAL FLOW RETURN (P=DIF NOK NOISY NSD)

Next: !p572

DHW FLOW SWITCH OPERATION

SELECTOR SWITCH TO HOT WATER
GAIN ACCESS TO PCB (USE INSULATION MAT AS NECESSARY)

Next: p107, ?108, ?110

SYSTEM PRESSURE CHECK

Next: p1183, !f1178

RESISTANCE WATER PRESSURE SWITCH

DISCONNECT THE WIRES

Next: !p1181, !f1182

VOLTAGE AT PUMP

REMOVE THE COVER FROM THE PUMP
APPLY DEMAND

Next: !p1197, f1198

VOLTAGE PUMP AT PCB

{SELHWCHON}
GAIN ACCESS TO PCB (USE INSULATION MAT AS NECESSARY)

Next: !p1199, !f1200

RESISTANCE SENSOR TEMP DHW

REMOVE THE LEAD FROM THE DHW SENSOR

Next: p1433, !f1434

VOLTAGE FROM SWITCH LIVE

{SELHWCHON}
NO DEMANDS FOR CH
GAIN ACCESS TO PCB (USE INSULATION MAT AS NECESSARY)

Next: !p1460, !f1461

RESISTANCE FUSE F1 (FUSED SPUR)

Next: !p1472, f1473

FUSE FURTHER INVESTIGATION F1

Next: !p1474, !f1475

RESISTANCE FUSE F2 ( APPLIANCE)

REMOVE CONTROL BOX COVER
REMOVE THE FUSE AND HOLDER FROM THE LIVE (BROWN)

Next: p1478, f1479

FUSE FURTHER INVESTIGATION F2

Next: !p1480, !f1481

RESISTANCE FAN (DC)_FUSE

REMOVE THE 4 WIRE CONNECTOR FROM THE FAN

Next: !p1506, !f1507

RESISTANCE SENSOR TEMP PRIMARY

REMOVE THE LEAD FROM THE FLOW SENSOR

Next: !p1519, !f1520

RESISTANCE PUMP AND HARNESS

REMOVE CONNECTOR X3 FROM THE PCB

Next: p1616, f1617

RESISTANCE PUMP

DISCONNECT THE MAINS CABLE TO THE PUMP

Next: !p1618, !f1619

RESISTANCE GAS VALVE

DISCONNECT THE LEAD FROM THE GAS VALVE

Next: !p1622, !f1623

RESISTANCE DIVERTER VALVE HEAD

REMOVE DIVERTER VALVE HEAD FROM BODY

Next: !p1626, !f1627

RESISTANCE IGNITER

REMOVE THE FLAME IGNITION HARNESS FROM THE SPARK GENERATOR

Next: !p1630, !f1631

RESISTANCE AC FAN

REMOVE THE 3 WIRE CONNECTOR FROM THE FAN

Next: !p1634, !f1635

RESISTANCE FAN DC

REMOVE THE 4 WIRE CONNECTOR FROM THE FAN

Next: !p1637, !f1638

RESISTANCE SENSOR TEMP PRIMARY

REMOVE THE LEAD FROM THE FLOW SENSOR

Next: !p1642, !f1643

RESISTANCE SENSOR FLUE OVERHEAT STAT

REMOVE THE FLUE SENSOR FROM THE TOP OF THE HEAT EXCHANGER
(TWIST BAYONET FITTING)

Next: !p1671, !f1672

RESISTANCE SENSOR OVERHEAT STAT

UNPLUG THE LEAD FROM THE OVERHEAT STAT

Next: !p1674, !f1675

RESISTANCE SENSOR TEMP DHW

REMOVE THE LEAD FROM THE DHW SENSOR

Next: !p1679, !f1680

SYSTEM PRESSURE CHECK

Next: p1682, !f1683

INSPECTION RETURN FILTER

DRAIN BOILER HEATING CIRCUIT

Next: !p1745, !f1746

TEMPERATURE DIFFERENTIAL CH

{SELHWCHON}
TURN

Next: !p1775, f1776

DIVERTER VALVE BLOCKAGE

ISOLATE COLD MAINS I

Next: !p1777, !f1778

RESISTANCE ELECTRODE LEAD

REMOVE SPARK AND EARTH LEADS FROM ELECTRODE AND SPARK GENERATOR

Next: !p1971, !f1905

RESISTANCE GAS VALVE AND SOLENOID MAIN AND HARNESS

DISCONNECT CONNECTOR MARKED X3 FROM PCB

Next: !p1946, f1947

RESISTANCE GAS VALVE

DISCONNECT THE LEAD FROM THE GAS VALVE

Next: !p1948, !f1949

RESISTANCE GAS VALVE

DISCONNECT THE LEAD FROM THE GAS VALVE

Next: !p1952, !f1953

RESISTANCE SPARK GENERATOR AND LEADS

REMOVE SPARK LEAD AND EARTH WIRE FROM ELECTRODE

Next: p1991, f1986

RESISTANCE ELECTRODE LEAD

REMOVE SPARK AND EARTH LEADS FROM ELECTRODE AND SPARK GENERATOR

Next: !p1989, !f1997

RESISTANCE SENSOR FLUE OVERHEAT STAT

REMOVE THE FLUE SENSOR FROM THE TOP OF THE HEAT EXCHANGER
(TWIST BAYONET FITTING)

Next: !p2019, !f2020

INSPECTION DIVERTER VALVE POSITION CH

{SELHWCHON}
ALL HEATING CONTROLS CALLING
REMOVE DIVERTER VALVE MOTOR/ACTUATOR

Next: p2045, f2046

VOLTAGE DIVERTER VALVE PCB CH

FUNCTION SELECTOR IN

Next: p2047, !f2048

INSPECTION DIVERTER VALVE POSITION CH

{SELHWCHON}
ALL HEATING CONTROLS CALLING
REMOVE DIVERTER VALVE MOTOR/ACTUATOR

Next: p2056, f2057

VOLTAGE DIVERTER VALVE PCB CH

FUNCTION SELECTOR IN

Next: p2058, !f2059

TEMPERATURE DIFFERENTIAL CH

{SELHWCHON}
TURN

Next: !p2067, f2068

DIVERTER VALVE BLOCKAGE

ISOLATE COLD MAINS I

Next: !p2069, !f2070

VOLTAGE MAINS IN AT PCB

Next: !p2079, f2080

VOLTAGE SELECTOR SWITCH

SELECTOR SWITCH IN HOT WATER

Next: !p2081, f2082

VOLTAGE SELECTOR SWITCH INPUT

SELECTOR SWITCH IN HOT WATER

Next: !p2083, !f2084

RESISTANCE SENSOR OVERHEAT STAT

UNPLUG THE LEAD FROM THE OVERHEAT STAT

Next: !p2130, !f2131

RESISTANCE SELECTOR SWITCH (RESET)

{SELHWCHON}
REMOV

Next: !p2133, !f2134

RESISTANCE SENSOR FLUE OVERHEAT STAT

REMOVE THE FLUE SENSOR FROM THE TOP OF THE HEAT EXCHANGER
(TWIST BAYONET FITTING)

Next: !p2149, !f2150

RESISTANCE SELECTOR SWITCH (RESET)

{SELHWCHON}
REMOV

Next: !p2152, !f2153

RESISTANCE SENSOR FLUE OVERHEAT AND HARNESS

REMOVE THE CONNECTOR X401 FROM THE CONTROL BOX

Next: !p2161, f2162

RESISTANCE SENSOR FLUE OVERHEAT STAT

REMOVE THE FLUE SENSOR FROM THE TOP OF THE HEAT EXCHANGER
(TWIST BAYONET FITTING)

Next: !p2163, !f2164

INSPECTION FLOW SWITCH ASSEMBLY

ISOLATE MAINS WATER

Next: !p2212, !f2213

RESISTANCE SENSOR TEMP PRIMARY

REMOVE THE LEAD FROM THE FLOW SENSOR

Next: !p2229, !f2230

RESISTANCE GAS VALVE

DISCONNECT THE LEAD FROM THE GAS VALVE

Next: !p2237, !f2238

GAS VALVE VOLTAGE (PCB)

SELECTOR SWITCH TO HOT WATER
GAIN ACCESS TO PCB (USE INSULATION MAT AS NECESSARY)

Next: !p2241, !f2242

RESISTANCE IGNITER

REMOVE THE FLAME IGNITION HARNESS FROM THE SPARK GENERATOR

Next: !p2245, !f2246

RESISTANCE PUMP

DISCONNECT THE MAINS CABLE TO THE PUMP

Next: !p2249, !f2250

VOLTAGE PUMP AT PCB

{SELHWCHON}
GAIN ACCESS TO PCB (USE INSULATION MAT AS NECESSARY)

Next: !p2253, !f2254

RESISTANCE AC FAN

REMOVE THE 3 WIRE CONNECTOR FROM THE FAN

Next: !p2257, !f2258

VOLTAGE AC TO FAN

GAIN ACCESS TO PCB (USE INSULATION MAT AS NECESSARY)

Next: !p2261, !f2262

RESISTANCE SENSOR FLUE OVERHEAT STAT

REMOVE THE FLUE SENSOR FROM THE TOP OF THE HEAT EXCHANGER
(TWIST BAYONET FITTING)

Next: !p2265, !f2266

RESISTANCE SENSOR TEMP DHW

REMOVE THE LEAD FROM THE DHW SENSOR

Next: !p2269, !f2270

RESISTANCE DIVERTER VALVE HEAD

REMOVE DIVERTER VALVE HEAD FROM BODY

Next: !p2273, !f2274

VOLTAGE DIVERTER VALVE PCB

SELECTOR SWITCH TO HOT WATER
GAIN ACCESS TO PCB (USE INSULATION MAT AS NECESSARY)

Next: p563, !f566

VOLTAGE AT PUMP

REMOVE THE COVER FROM THE PUMP
APPLY DEMAND

Next: !p337, f338

VOLTAGE PUMP AT PCB

{SELHWCHON}
GAIN ACCESS TO PCB (USE INSULATION MAT AS NECESSARY)

Next: !p339, !f340

RESISTANCE OVERHEAT STAT AND HARNESS

UNPLUG CONNECTOR X401 FROM THE PCB

Next: p2087, f2129

VOLTAGE AT PUMP

REMOVE THE COVER FROM THE PUMP
APPLY DEMAND

Next: !p445, f574

TEMPERATURE DIFFERENTIAL CH

{SELHWCHON}
TURN

Next: !p2053, f2044

VOLTAGE DIVERTER VALVE PCB CH

FUNCTION SELECTOR IN

Next: p556, !f557

VOLTAGE PUMP AT PCB

{SELHWCHON}
GAIN ACCESS TO PCB (USE INSULATION MAT AS NECESSARY)

Next: !p575, !f576

RESISTANCE SENSOR TEMP PRIMARY AND HARNESS

REMOVE THE PLUG X401 FROM THE PCB

Next: !p589, f586

RESISTANCE SENSOR TEMP PRIMARY

REMOVE THE LEAD FROM THE FLOW SENSOR

Next: !p587, !f588

RESISTANCE SENSOR TEMP DHW AND HARNESS

REMOVE THE PLUG X400 FROM THE PCB

Next: !p595, f592

RESISTANCE SENSOR TEMP DHW

REMOVE THE LEAD FROM THE DHW SENSOR

Next: !p593, !f594

SYSTEM PRESSURE CHECK

Next: p606, !f600

RESISTANCE WATER PRESSURE SWITCH

DISCONNECT THE WIRES

Next: !p1001, !f614

BOILER RESET

Next: p642, f655

VOLTAGE AT PUMP

REMOVE THE COVER FROM THE PUMP
APPLY DEMAND

Next: !p645, f646

VOLTAGE PUMP AT PCB

{SELHWCHON}
GAIN ACCESS TO PCB (USE INSULATION MAT AS NECESSARY)

Next: !p647, !f648

RESISTANCE SELECTOR SWITCH (RESET)

{SELHWCHON}
REMOV

Next: !p656, !f657

RESISTANCE SENSOR FLUE OVERHEAT AND HARNESS

REMOVE THE CONNECTOR X401 FROM THE CONTROL BOX

Next: p2137, f2148

IS FAN RUNNING

{SELHWCHON}

Next: p722, f723

RESISTANCE FAN HARNESS AC

REMOVE THE 3 WIRE CONNECTOR FROM THE FAN ASSEMBLY
REMOVE CONNECTOR X2 FROM THE PCB

Next: p791, !f792

RESISTANCE SENSOR TEMP PRIMARY

REMOVE THE LEAD FROM THE FLOW SENSOR

Next: !p771, !f772

RESISTANCE SENSOR TEMP DHW

REMOVE THE LEAD FROM THE DHW SENSOR

Next: !p775, !f776

SYSTEM PRESSURE CHECK

Next: p779, !f780

RESISTANCE SENSOR FLUE OVERHEAT STAT

REMOVE THE FLUE SENSOR FROM THE TOP OF THE HEAT EXCHANGER
(TWIST BAYONET FITTING)

Next: !p785, !f786

RESISTANCE SENSOR OVERHEAT STAT

UNPLUG THE LEAD FROM THE OVERHEAT STAT

Next: !p789, !f790

RESISTANCE GAS VALVE AND SOLENOID MAIN AND HARNESS

DISCONNECT CONNECTOR MARKED X3 FROM PCB

Next: p807, f808

RESISTANCE GAS VALVE

DISCONNECT THE LEAD FROM THE GAS VALVE

Next: !p831, !f810

RESISTANCE PUMP

DISCONNECT THE MAINS CABLE TO THE PUMP

Next: !p829, !f814

RESISTANCE FAN DC

REMOVE THE 4 WIRE CONNECTOR FROM THE FAN

Next: !p830, !f818

RESISTANCE AC FAN

REMOVE THE 3 WIRE CONNECTOR FROM THE FAN

Next: !p896, !f897

RESISTANCE DIVERTER VALVE HEAD

REMOVE DIVERTER VALVE HEAD FROM BODY

Next: !p828, !f826

DHW ISOLATING VALVE

Next: p1692, !f98

VOLTAGE AT PUMP

REMOVE THE COVER FROM THE PUMP
APPLY DEMAND

Next: !p997, f998

VOLTAGE PUMP AT PCB

{SELHWCHON}
GAIN ACCESS TO PCB (USE INSULATION MAT AS NECESSARY)

Next: !p999, !f1000

RESISTANCE SENSOR TEMP PRIMARY

REMOVE THE LEAD FROM THE FLOW SENSOR

Next: !p1020, !f1016

INSPECTION FLOW SWITCH ASSEMBLY

ISOLATE MAINS WATER

Next: !p1030, !f1031

VOLTAGE AC TO FAN

GAIN ACCESS TO PCB (USE INSULATION MAT AS NECESSARY)

Next: p768, !f113

RESISTANCE FAN HARNESS

REMOVE THE 4 WIRE CONNECTOR FROM THE FAN
REMOVE CONNECTOR X401 FROM THE PCB

Next: p1114, !f1115

VOLTAGE AC TO FAN

GAIN ACCESS TO PCB (USE INSULATION MAT AS NECESSARY)

Next: p1100, !f2086

RESISTANCE FAN HARNESS AC

REMOVE THE 3 WIRE CONNECTOR FROM THE FAN ASSEMBLY
REMOVE CONNECTOR X2 FROM THE PCB

Next: p1539, !f1107

VOLTAGE FAN SUPPLY

GAIN ACCESS TO PCB (USE INSULATION MAT AS NECESSARY)

Next: p1116, !f1117

VOLTAGE DC FAN SPEED ON START UP

Next: !p1306, !f1307

VOLTAGE DC FAN DEMAND START-UP

Next: !p1549, !f1550

RESISTANCE WATER PRESSURE SWITCH AND HARNESS

REMOVE THE PLUG X400 FROM THE PCB

Next: !p1179, f1180

DOES PUMP RUN

Next: p1189, f1196

PUMP RUNS (LIMPET TEST)

Next: p1177, !f1201

RESISTANCE DHW FLOW SWITCH HARNESS

REMOVE CONNECTOR X400 FROM PCB AND CONNECTOR FROM THE HALL SENSOR ON THE FLOW SWITCH

Next: p1029, !f1291

IS BOILER TEMP LOW

Next: !p1431, f1443

OBSERVATION ISOLATE DHW DOES DHW DEMAND STOP

ISOLATE THE COLD WATER SUPPLY TO THE APPLIANCE

Next: p1435, !f1436

OBSERVATION REMOVE HALL SENSOR DOES DHW DEMAND STOP

REMOVE DHW HALL SENSOR FROM FLOW VALVE

Next: p1437, !f1438

OBSERVATION DISCONNECT HALL SENSOR DOES DHW DEMAND STOP

REMOVE DHW HALL SENSOR FROM FLOW VALVE
REMOVE CONNECTOR FROM THE HALL SENSOR AND MAKE SAFE

Next: p1439, !f1440

RESISTANCE DHW FLOW SWITCH HARNESS

REMOVE CONNECTOR X400 FROM PCB AND CONNECTOR FROM THE HALL SENSOR ON THE FLOW SWITCH

Next: !p1441, !f1442

RESISTANCE SENSOR TEMP PRIMARY

REMOVE THE LEAD FROM THE FLOW SENSOR

Next: p1456, !f1457

IS INTEGRAL TIMER FITTED

Next: p1458, f1459

IS VOLTAGE PRESENT FROM INTEGRAL TIMER

{SELHWCHON}
GAIN

Next: !p1462, !f1463

VOLTAGE MAINS POWER INPUT TO APPLIANCE

REMOVE CONTROL BOX COVER

Next: p1470, f1471

VOLTAGE AT PCB MAINS

REMOVE CONTROL BOX COVER

Next: p1476, f1477

REMOVE DHW FLOW SWITCH DOES DISPLAY NOW WORK

REMOVE DHW HALL SENS

Next: p1484, !f1485

FUSE FURTHER INVESTIGATION F3

Next: !p1482, !f1483

REMOVE CONNECTOR X400 DOES DISPLAY NOW WORK

REMOVE CONNECTOR X400 FROM PCB

Next: p1486, !f1487

FAN RUNS SELF CHECK

SELECTOR SWITCH TO HOT WATER

Next: p1488, ?1490, ?1492

REMOVE FAN CONNECTOR DOES DISPLAY NOW WORK

REMOVE CONNECTOR X401 FROM PCB

Next: p1567, f1505

VOLTAGE AC TO FAN

GAIN ACCESS TO PCB (USE INSULATION MAT AS NECESSARY)

Next: p1558, f2078

RESISTANCE SENSOR TEMP PRIMARY AND HARNESS

REMOVE THE PLUG X401 FROM THE PCB

Next: !p1517, f1518

VOLTAGE DC PCB SPEED REQUEST

Next: !p1525, !f1526

RESISTANCE FAN HARNESS

REMOVE THE 4 WIRE CONNECTOR FROM THE FAN
REMOVE CONNECTOR X401 FROM THE PCB

Next: p1543, !f1548

VOLTAGE FAN SUPPLY

GAIN ACCESS TO PCB (USE INSULATION MAT AS NECESSARY)

Next: p1158, !f1547

RESISTANCE FAN HARNESS

REMOVE THE 4 WIRE CONNECTOR FROM THE FAN
REMOVE CONNECTOR X401 FROM THE PCB

Next: p1552, !f1553

VOLTAGE FAN SUPPLY

GAIN ACCESS TO PCB (USE INSULATION MAT AS NECESSARY)

Next: p1554, !f1555

VOLTAGE DC PCB SPEED REQUEST

Next: !p1556, !f1557

RESISTANCE FAN HARNESS AC

REMOVE THE 3 WIRE CONNECTOR FROM THE FAN ASSEMBLY
REMOVE CONNECTOR X2 FROM THE PCB

Next: p1559, !f1560

RESISTANCE FAN HARNESS

REMOVE THE 4 WIRE CONNECTOR FROM THE FAN
REMOVE CONNECTOR X401 FROM THE PCB

Next: p1561, !f1562

VOLTAGE FAN SUPPLY

GAIN ACCESS TO PCB (USE INSULATION MAT AS NECESSARY)

Next: p1563, !f1564

VOLTAGE DC FAN DEMAND START-UP

Next: !p1565, !f1566

RESISTANCE FAN HARNESS

REMOVE THE 4 WIRE CONNECTOR FROM THE FAN
REMOVE CONNECTOR X401 FROM THE PCB

Next: p1568, !f1569

VOLTAGE FAN SUPPLY

GAIN ACCESS TO PCB (USE INSULATION MAT AS NECESSARY)

Next: p1570, !f1571

VOLTAGE DC FAN SPEED ON START UP

Next: !p1572, !f1573

RESISTANCE GAS VALVE AND SOLENOID MAIN AND HARNESS

DISCONNECT CONNECTOR MARKED X3 FROM PCB

Next: p1620, f1621

RESISTANCE DIVERTER VALVE AND HARNESS

REMOVE CONNECTOR X3 FROM THE PCB
REMOVE DIVERTER VALVE HEAD FROM BODY

Next: p1624, f1625

RESISTANCE IGNITER AND HARNESS

REMOVE CONNECTOR X2 FROM THE PCB

Next: p1628, f1629

RESISTANCE FAN AND HARNESS AC

REMOVE CONNECTOR X2 FROM THE PCB

Next: p1632, f1633

RESISTANCE FAN AND HARNESS DC

DISCONNECT CONNECTOR X401 FROM THE PCB

Next: p1639, f1636

RESISTANCE SENSOR TEMP PRIMARY AND HARNESS

REMOVE THE PLUG X401 FROM THE PCB

Next: p1668, f1641

RESISTANCE SENSOR FLUE OVERHEAT AND HARNESS

REMOVE THE CONNECTOR X401 FROM THE CONTROL BOX

Next: p1669, f1670

RESISTANCE OVERHEAT STAT AND HARNESS

UNPLUG CONNECTOR X401 FROM THE PCB

Next: p1676, f1673

RESISTANCE SENSOR TEMP DHW AND HARNESS

REMOVE THE PLUG X400 FROM THE PCB

Next: p1677, f1678

RESISTANCE WATER PRESSURE SWITCH AND HARNESS

REMOVE THE PLUG X400 FROM THE PCB

Next: p1686, f1681

RESISTANCE WATER PRESSURE SWITCH

DISCONNECT THE WIRES

Next: !p1684, !f1685

INSPECTION ELECTRODE SPARK GAP

REMOVE THE BURNER ASSEMBLY FROM THE BOILER

Next: p1687, !f1688

INSPECTION DETECTION ELECTRODE

DISCONNECT THE LEAD FROM THE DETECTION ELECTRODE
REMOVE DETECTION ELECTRODE FROM BURNER

Next: p2214, !f1690

WATER SUPPLY TO PREMISES

TURN ON A COLD WATER TAP

Next: p97, !f1696

INSPECTION RETURN FILTER

DRAIN BOILER HEATING CIRCUIT

Next: p567, !f1743

PUMP LIMPET

Next: p1752, !f1753

RESISTANCE SENSOR TEMP DHW

REMOVE THE LEAD FROM THE DHW SENSOR

Next: p1754, !f1755

RESISTANCE SENSOR TEMP PRIMARY

REMOVE THE LEAD FROM THE FLOW SENSOR

Next: p2064, !f1757

TEMPERATURE DIFFERENTIAL DHW

ATTACH FGA TEMPERATURE CLAMPS
ON FLOW AND RETURN PIPES AS SHOWN
DHW THERMOSTAT ON MAX

Next: !p1773, f1774

GAS INLET PRESSURE

{SELHWCHON}
SET D

Next: p1900, !f1901

CAN SPARKING BE SEEN (EXPLOSIVE IGN)

{SELHWCHON}
REMOV

Next: p1916, f1903

INSPECTION CONDENSATE PIPE

Next: p1906, !f1907

INSPECTION FLUE

Next: p1908, !f1909

INSPECTION ELECTRODE SPARK GAP

REMOVE THE BURNER ASSEMBLY FROM THE BOILER

Next: p1910, !f1911

GAS INLET PRESSURE

{SELHWCHON}
SET D

Next: p202, !f203

INSPECTION BURNER

REMOVE THE FRONT OF THE COMBUSTION CHAMBER

Next: p1912, !f1913

INSPECTION HEAT EXCHANGER

Next: p1929, !f1915

INSPECTION PRESSURE SENSING VENTURI

REMOVE THE COMPENSATION TUBE FROM THE FAN ASSEMBLY

Next: !p1931, !f1930

GAS INLET PRESSURE

{SELHWCHON}
SET D

Next: p2001, !f195

PRESSURE GAS INLET AND DROP

{SELHWCHON}
SET D

Next: p1939, ?1940, ?1942

INSPECTION CONDENSATE PIPE

Next: p1956, !f1957

GAS VALVE VOLTAGE (PCB)

SELECTOR SWITCH TO HOT WATER
GAIN ACCESS TO PCB (USE INSULATION MAT AS NECESSARY)

Next: p1944, f1945

RESISTANCE GAS VALVE AND SOLENOID MAIN AND HARNESS

DISCONNECT CONNECTOR MARKED X3 FROM PCB

Next: p1950, f1951

INSPECTION FLUE

Next: p1968, !f1955

INSPECTION FLUE

Next: p1958, !f1959

INSPECTION ELECTRODE SPARK GAP

REMOVE THE BURNER ASSEMBLY FROM THE BOILER

Next: p1960, !f1961

INSPECTION BURNER

REMOVE THE FRONT OF THE COMBUSTION CHAMBER

Next: p1962, !f1963

INSPECTION HEAT EXCHANGER

Next: p1964, !f1965

INSPECTION PRESSURE SENSING VENTURI

REMOVE THE COMPENSATION TUBE FROM THE FAN ASSEMBLY

Next: !p1966, !f1967

INSPECTION PRESSURE SENSING VENTURI

REMOVE THE COMPENSATION TUBE FROM THE FAN ASSEMBLY

Next: !p1969, !f1970

CAN SPARKING BE SEEN

{SELHWCHON}
REMOV

Next: !p1973, f1979

RESISTANCE SPARK GENERATOR HARNESS

REMOVE CONNECTOR FROM SPARK GENERATOR
REMOVE CONNECTOR X2 FROM THE PCB

Next: p1994, !f1992

VOLTAGE SPARK GENERATOR

{SELHWCHON}
GAIN

Next: p1998, !f1995

VOLTAGE SPARK GENERATOR WITH LEAD

{SELHWCHON}
GAIN

Next: !p1999, !f2000

INSPECTION CONDENSATE PIPE

Next: p2280, !f2009

RESISTANCE SENSOR FLUE OVERHEAT AND HARNESS

REMOVE THE CONNECTOR X401 FROM THE CONTROL BOX

Next: p653, f2018

INSPECTION CONDENSATE PIPE

Next: p204, !f205

TEMPERATURE DIFFERENTIAL CH

{SELHWCHON}
TURN

Next: p453, f2055

INSPECTION BURNER

REMOVE THE FRONT OF THE COMBUSTION CHAMBER

Next: p206, !f207

INSPECTION RETURN FILTER

DRAIN BOILER HEATING CIRCUIT

Next: !p2051, !f2052

RESISTANCE DIVERTER HARNESS

REMOVE CONNECTOR X3 FROM PCB
REMOVE DIVERTER HEAD FROM ITS CONNECTOR

Next: !p2049, !f2050

INSPECTION RETURN FILTER

DRAIN BOILER HEATING CIRCUIT

Next: !p2062, !f2063

RESISTANCE DIVERTER HARNESS

REMOVE CONNECTOR X3 FROM PCB
REMOVE DIVERTER HEAD FROM ITS CONNECTOR

Next: !p2060, !f2061

INSPECTION HEAT EXCHANGER

Next: p2275, !f305

TEMPERATURE DIFFERENTIAL DHW

ATTACH FGA TEMPERATURE CLAMPS
ON FLOW AND RETURN PIPES AS SHOWN
DHW THERMOSTAT ON MAX

Next: p2065, f2066

INSPECTION BURNER

REMOVE THE FRONT OF THE COMBUSTION CHAMBER

Next: p2071, !f2072

INSPECTION HEAT EXCHANGER

Next: p2073, !f2074

INSPECTION FLUE

Next: !p2077, !f2076

INSPECTION FLUE

Next: !p210, !f211

BOILER RESET

Next: p439, f2132

BOILER RESET

Next: p697, f2151

INSPECTION HEAT EXCHANGER

Next: !p2157, !f2158

INSPECTION FLUE

Next: p706, !f2171

VOLTAGE FROM SELECTOR SWITCH

{SELHWCHON}
CH THERMOSTAT TO MAX
GAIN ACCESS TO PCB (USE INSULATION MAT AS NECESSARY)

Next: p2173, f2174

VOLTAGE FROM EXTERNAL CONTROLS

{SELHWCHON}
CH THERMOSTAT TO MAX

Next: p2177, !f2178

RESISTANCE HARNESS EXTERNAL CONTROLS TO PCB

REMOVE CONNECTOR X3 FROM THE PCB

Next: p2179, !f2180

VOLTAGE FROM INTEGRAL TIMER

{SELHWCHON}

Next: !p2181, ?2183, ?2185

VOLTAGE TO INTEGRAL TIMER

{SELHWCHON}

Next: !p2189, !f2190

VOLTAGE LINKED CONNECTOR

{SELHWCHON}

Next: !p2187, !f2188

VOLTAGE FROM SELECTOR SWITCH

{SELHWCHON}
CH THERMOSTAT TO MAX
GAIN ACCESS TO PCB (USE INSULATION MAT AS NECESSARY)

Next: p2192, f2193

VOLTAGE FROM EXTERNAL CONTROLS

{SELHWCHON}
CH THERMOSTAT TO MAX

Next: p2196, !f2197

RESISTANCE HARNESS EXTERNAL CONTROLS TO PCB

REMOVE CONNECTOR X3 FROM THE PCB

Next: p2198, !f2199

VOLTAGE FROM INTEGRAL TIMER

{SELHWCHON}

Next: !p2200, ?2202, ?2204

VOLTAGE TO INTEGRAL TIMER

{SELHWCHON}

Next: !p2208, !f2209

VOLTAGE LINKED CONNECTOR

{SELHWCHON}

Next: !p2206, !f2207

OBSERVATION DISCONNECT EXTERNAL CONTROLS

DISCONNECT EXTERNAL

Next: !p2217, !f2218

INSPECTION PRESSURE SENSING VENTURI

REMOVE THE COMPENSATION TUBE FROM THE FAN ASSEMBLY

Next: p208, !f2279

INSPECTION PRESSURE SENSING VENTURI

REMOVE THE COMPENSATION TUBE FROM THE FAN ASSEMBLY

Next: p2292, !f2297

RESISTANCE DETECTION LEAD

REMOVE BOTH ENDS OF THE FLAME SENSE HARNESS, FROM THE ELECTRODE AND FROM X501 ON THE PCB

Next: p2293, !f2294

INSPECTION DETECTION ELECTRODE

DISCONNECT THE LEAD FROM THE DETECTION ELECTRODE
REMOVE DETECTION ELECTRODE FROM BURNER

Next: !p2295, !f2296

RESISTANCE SENSOR TEMP DHW

REMOVE THE LEAD FROM THE DHW SENSOR

Next: !p301, !f302

GAS INLET PRESSURE

{SELHWCHON}
SET D

Next: p1751, !f537

INSPECTION DIVERTER VALVE DHW POSITION

SELECTOR SWITCH IN HOT WATER
REMOVE DIVERTER VALVE MOTOR

Next: p280, f281

INSPECTION CONDENSATE PIPE

Next: p984, !f704

RESISTANCE SENSOR TEMP DHW

REMOVE THE LEAD FROM THE DHW SENSOR

Next: p259, !f260

RESISTANCE SENSOR TEMP PRIMARY

REMOVE THE LEAD FROM THE FLOW SENSOR

Next: p310, !f261

CH OPERATION (FOR HEAT EX DIAG)

{SELHWCHON}
FLOW AND RETURN VALVES FULLY OPEN
CH THERMOSTAT SET TO MAX

Next: !p264, ?266, ?268

INSPECTION DIVERTER VALVE SPINDLE

REMOVE THE DIVERTER VALVE ACTUATOR FROM THE DIVERTER VALVE BODY

Next: p286, !f287

INSPECTION HEAT EXCHANGER DHW

DRAIN PRIMARY CIRCUIT OF BOILER DOWN
TURN OFF HW ISOLATION VALVE

Next: !p288, !f289

COMBUSTION READINGS

{SELHWCHON}
REMOVE COMBUSTION TESTING POINT CAP FROM BOILER

Next: p315, !f547

PUMP LIMPET

Next: p1772, !f319

PUMP LIMPET

Next: p262, !f333

RESISTANCE SENSOR TEMP PRIMARY

REMOVE THE LEAD FROM THE FLOW SENSOR

Next: p403, !f418

EXPANSION VESSEL PRESSURE

BOILER DISCHARGED

Next: !p370, !f371

INSPECTION DIVERTER VALVE POSITION CH

{SELHWCHON}
ALL HEATING CONTROLS CALLING
REMOVE DIVERTER VALVE MOTOR/ACTUATOR

Next: p391, f555

PUMP RUNS (LIMPET TEST)

Next: p397, !f398

BYPASS PIPE TEMPERATURE

{SELHWCHON}
USE T

Next: p399, !f400

INSPECTION RETURN FILTER

DRAIN BOILER HEATING CIRCUIT

Next: !p401, !f402

DIVERTER BLOCKAGE CH

ISOLATE COLD MAINS I

Next: p1736, !f406

DOES PUMP RUN

Next: p443, f444

PUMP RUNS (LIMPET TEST)

Next: p447, !f448

RESISTANCE SENSOR TEMP PRIMARY

REMOVE THE LEAD FROM THE FLOW SENSOR

Next: p449, !f529

RESISTANCE SENSOR TEMP DHW

REMOVE THE LEAD FROM THE DHW SENSOR

Next: p451, !f528

TEMPERATURE DIFFERENTIAL DHW

ATTACH FGA TEMPERATURE CLAMPS
ON FLOW AND RETURN PIPES AS SHOWN
DHW THERMOSTAT ON MAX

Next: p2021, f454

CH TEST OVERHEAT

{SELHWCHON}
TURN

Next: !p462, ?466, ?468

RESISTANCE DIVERTER HARNESS

REMOVE CONNECTOR X3 FROM PCB
REMOVE DIVERTER HEAD FROM ITS CONNECTOR

Next: !p558, !f559

RESISTANCE DIVERTER HARNESS

REMOVE CONNECTOR X3 FROM PCB
REMOVE DIVERTER HEAD FROM ITS CONNECTOR

Next: !p564, !f565

TEMPERATURE DIFFERENTIAL FLOW RETURN

{SELHWCHON}
CH TH

Next: !p568, ?569, ?571

RESISTANCE WATER PRESSURE SWITCH AND HARNESS

REMOVE THE PLUG X400 FROM THE PCB

Next: !p611, f612

DOES PUMP RUN

Next: p643, f644

PUMP RUNS (LIMPET TEST)

Next: p649, !f650

RESISTANCE SENSOR TEMP PRIMARY

REMOVE THE LEAD FROM THE FLOW SENSOR

Next: p651, !f652

RESISTANCE SENSOR TEMP DHW

REMOVE THE LEAD FROM THE DHW SENSOR

Next: p2010, !f654

CH TEST LOCKOUT

{SELHWCHON}
TURN

Next: p658, f1744

HW TEST LOCKOUT

SELECTOR SWITCH TO H

Next: !p668, !f669

INSPECTION CONDENSATE PIPE

Next: p2165, !f703

INSPECTION BURNER

REMOVE THE FRONT OF THE COMBUSTION CHAMBER

Next: p2156, !f708

RESISTANCE FAN HARNESS

REMOVE THE 4 WIRE CONNECTOR FROM THE FAN
REMOVE CONNECTOR X401 FROM THE PCB

Next: p797, !f795

RESISTANCE SENSOR TEMP PRIMARY AND HARNESS

REMOVE THE PLUG X401 FROM THE PCB

Next: p769, f770

RESISTANCE SENSOR TEMP DHW AND HARNESS

REMOVE THE PLUG X400 FROM THE PCB

Next: p773, f774

RESISTANCE WATER PRESSURE SWITCH AND HARNESS

REMOVE THE PLUG X400 FROM THE PCB

Next: p777, f778

RESISTANCE SENSOR FLUE OVERHEAT AND HARNESS

REMOVE THE CONNECTOR X401 FROM THE CONTROL BOX

Next: p783, f784

RESISTANCE WATER PRESSURE SWITCH

DISCONNECT THE WIRES

Next: !p781, !f782

RESISTANCE OVERHEAT STAT AND HARNESS

UNPLUG CONNECTOR X401 FROM THE PCB

Next: !p787, f788

VOLTAGE AC TO FAN

GAIN ACCESS TO PCB (USE INSULATION MAT AS NECESSARY)

Next: p1551, !f794

VOLTAGE FAN SUPPLY

GAIN ACCESS TO PCB (USE INSULATION MAT AS NECESSARY)

Next: p798, !f799

VOLTAGE DC FROM FAN

{SELHWCHON}

Next: p1524, !f804

RESISTANCE PUMP AND HARNESS

REMOVE CONNECTOR X3 FROM THE PCB

Next: p811, f812

RESISTANCE FAN AND HARNESS DC

DISCONNECT CONNECTOR X401 FROM THE PCB

Next: p815, f816

RESISTANCE FAN AND HARNESS AC

REMOVE CONNECTOR X2 FROM THE PCB

Next: p819, f820

RESISTANCE DIVERTER VALVE AND HARNESS

REMOVE CONNECTOR X3 FROM THE PCB
REMOVE DIVERTER VALVE HEAD FROM BODY

Next: !p823, f824

INSPECTION FLOW SWITCH ASSEMBLY

ISOLATE MAINS WATER

Next: !p99, !f1308

DOES PUMP RUN

Next: p320, f996

System Information

  • Total Tests: 700
  • Sequence Logic: Decoded from encrypted .seq file
  • Navigation: Dynamic based on pass/fail results
  • Source: 4731307 GW SWIFTFLOW 100 SIT Control