Glow-Warm Boiler Error Codes
Glow-worm Boiler Error Codes
Boiler Model
Fault Code
Cause of Problem
Betacom
Red LED on
Lockout – low water pressure (increase pressure to 1.5bar) and reset boiler
Betacom
Red LED flashing
Overheat – check both overheat stats
Betacom
Yellow LED flashing
Turn domestic hot water (DHW) control knob into temperature range and turn central heating (CH) temperature control knob into power (reset position) and wait for minimum of 30 seconds before turning into either summer or temperature position
Betacom
Yellow LED on
Flame present on the burner
Betacom
Green LED on
Boiler ready for operation
Betacom
Green LED off
No power to boiler – Check for 230volts into the appliance, check fuse on printed circuit board (PCB)
Betacom / Ultracom₂ cxi / sxi / 35
F00 / F10 / F71
Flow heating temperature sensor fault
Betacom / Ultracom₂ cxi / sxi / 35
F01 / F11
Return heating temperature sensor fault
Betacom / Ultracom₂ cxi / sxi / 35
F20
Overheating fault
Betacom / Ultracom₂ cxi / sxi / hxi / 35 / Flexicom cx / hx / sx
F9 / F22
Low water pressure (or ignition temperature rise too slow)
Betacom / Ultracom₂ cxi / sxi / 35
F26 / F77
Fault in gas valve
Betacom / Ultracom₂ cxi / sxi / 35 / CI / hxi / Xtramax HE
F27 / F16
Flame detection fault
All Boilers
F28 / F1 / F4
Ignition fault (flame detection)
Betacom / Ultracom₂ cxi / sxi / 35
F29
Loss of flame during operation
Betacom / Ultracom₂ cxi / sxi / 35
F32
Incorrect air pressure
Betacom / Ultracom₂ cxi / sxi / 35
F49
EBUS voltage fault
Betacom / Ultracom₂ cxi / sxi / 35
F61 / F62 / F63 / F64 / F65 / F67
Fault in the main board
Betacom / Ultracom₂ cxi / sxi / 35
F68
Fluctuation of flame signal
Betacom / Ultracom₂ cxi / sxi / 35
F70
User interface incompatible with the main board
Betacom / Ultracom₂ cxi / sxi / 35
F72 / F84
Permanent temperature difference between flow and return heating sensors
Betacom / Ultracom₂ cxi / sxi / 35
F73 / F74
Heating circuit pressure sensor fault
Betacom / Ultracom₂ cxi / sxi / 35
F76
Thermal fuse fault
Betacom / Ultracom₂ cxi / sxi / 35
F83
Thermal fuse fault
Betacom / Ultracom₂ cxi / sxi / 35
F85
Flow and Return heating sensor fault
Betacom / Ultracom₂ cxi / sxi / 35
F86
Underfloor heating contact fault
All Boilers
ERR / F12 / F18
User interface fault
Betacom c
Temperature 30 flashing
Fault on central heating (CH) thermistor
Betacom c
Temperature 40 flashing
Fault on DHW thermistor
Betacom c
Temperature 50 flashing
Fault on outside sensor
Betacom c
Temperature 60 flashing
Low system pressure
Betacom c
Temperature 70 flashing
Fault on APS
Betacom c
Temperature 80 flashing
Overheat open circuit
Betacom c
Temperature 90 flashing
Flame or gas failure
Compact e / s
No DHW
Check dhw microswitch / Check external controls, Please test for 230V on switch live contact
Compact e / s
No C/H
Check dhw microswitch if dhw demand led is lit / Check external controls, Please test for 230V on switch live contact
Compact e / s
No C/H but boiler is firing
Check divertor motor and cartridge / Check external controls, Please test for 230V on switch live contact
Compact e / s
Boiler locks out within 10 seconds
Check pump proving switch, air pressure switch and overheat state / Check pump proving switch, air pressure switch and overheat stat
Compact e / s
Poor burner pressure
Check burner pressure/ignition adjustment pots on PCB
Ci Range (plus) / Si range
F2
Fan/APS
All Boilers
F5
Overheat Fault
All Boilers
F6
Central heating flow thermistor
All Boilers
F7
Domestic hot water thermistor
All Boilers
F8
Tank thermistor fault
sxi / si / ci (plus) range / Xtramax HE
F9
Water pressure sensor fault (please contact GW technical department for further information)
All boilers
F10
Central return flow thermistor
All boilers
F11
Main board connection fault
Ci (plus) / cxi / hxi / si / sxi range
F12
Connection fault between main printed circtuit board (PCB) and display PCB
Ci (plus) / cxi / hxi / si / sxi range
F13
Main pcb connection fault
Ci (plus) / cxi / hxi / si / sxi range
F14
Central heating flow temperature > 95 degrees
Ci (plus) / cxi / si / sxi range
F15
Gas valve stepper motor fault
Ci (plus) / cxi / hxi / si / sxi range / Xtramax HE
F17
Power supply is less than 170v
Ci (plus) / cxi / hxi / si / sxi range / Xtramax HE
F19
Central heating thermistor unplugged
Ci (plus) / cxi / hxi / si / sxi range / Xtramax HE
F20
Software incompatibility
cxi / hxi / sxi range / Flexicom cx
F24
Central heating return temperature > 90 degrees
cxi / hxi / sxi / Xtrafast 96/120 / Xtrafast 96/120E1
F25 / F26 / F11
Poor circulation
ci range
F3
Air fault
ci range
F3
Air fault
cxi / sxi / hxi range/ Xtramax HE
F2 / F3
Fan
cxi / sxi range / Flexicom cx / hx / sx / hxi / Ultracom cxi / cx / hxi / sxi / Ultrapower sxi
F3
Fan unable to reach ignition speed
Flexicom cx / hx / sx / hxi / Ultracom cxi / cx / hxi / sxi
F9
Water pressure sensor fault, blocked flow filter or pump fault
Flexicom cx / hx / sx
F11
Flow and or return thermistor fault
Flexicom cx / hx / sx / Ultracom cxi / cx / hxi / sxi / Xtramax HE
F13
PCB memory or sensing fault
Flexicom cx / hx / sx / Ultracom cxi / cx / hxi / sxi / Xtramax HE
F14
Gas valve control defective
Flexicom cx / hx / sx / Ultracom cxi / cx / hxi / sxi / Xtramax HE
F15
E-bus voltage failure
All boilers
F25 / F23
Circulation fault
Flexicom cx / hx / sx / Ultracom cxi / cx / hxi / sxi
F43
Generic error
Flexicom cx / hx / sx / Ultracom cxi / cx / hxi / sxi
F70
Software incompatible
Flexicom cx / hx / sx / Ultracom cxi / cx / hxi / sxi
F73
Unable to see pump activate
Flexicom cx / hx / sx / Ultracom cxi / cx / hxi / sxi
F77
Condensate pump error (optional)t
hxi range
F9
Earlier models only (please contact GW technical department for further information)
hxi range
F9
Earlier models only (please contact GW technical department for further information)
Ultracom₂ 35 Store
F02 / F12
Hot water temperature sensor fault
Ultracom₂ 35 Store
F03 / F13 / F79
Storage tank temperature sensor faultt
Ultracom₂ 35 Store
F81
Overheating of hot water circuit
All Ultracom
No display or Er
loose connection X51
Xtramax HE Range
F24
Cental heating return temperature > 90 degrees
Xtramax HE Range
F25
Maximum temperature rise slope
Xtramax HE Range
F26
Maximum delta temperature
Xtrafast 96/120 Range
F00
No fault/td>
Xtrafast 96/120 Range / Xtrafast 96/120E1 Range
F02
Air flow fault
Xtrafast 96/120 Range / Xtrafast 96/120E1 Range
F05
Overheating
Xtrafast 96/120 Range / Xtrafast 96/120E1 Range
F06
Central heating thermistor/wiring fault
Xtrafast 96/120 Range / Xtrafast 96/120E1 Range
F08
Storage vessel thermistor/wiring fault
Xtrafast 96/120 Range / Xtrafast 96/120E1 Range
F09
System pressure sensor fault
Xtrafast 96/120 Range / Xtrafast 96/120E1 Range
F10
Xtrafast 96/120 Range / Xtrafast 96/120E1 Range
Xtrafast 96/120 Range / Xtrafast 96/120E1 Range
F13
Main printed circuit board (PCB) fault
Xtrafast 96/120 Range / Xtrafast 96/120E1 Range
F14
Central heating flow temperature > 97 degrees
Xtrafast 96/120 Range / Xtrafast 96/120E1 Range
F15
Gas mechanism fault
Xtrafast 96/120 Range / Xtrafast 96/120E1 Range
F20
Communication fault
Glow-worm Energy Boiler Range Error Codes
Fault Code
Cause of Problem
F.00
Flow temperature sensor
F.00
Flow temperature sensor
F.10
Flow temperature sensor short circuit
F.11
Flow temperature sensor short circuit
F.12 and F.91
Cylinder temperature sensor short circuit
F.13
Domestic hot water cylinder temperature sensor short circuit
F.20
Safety switch-off – overheating temperature reached
F.22
Safety switch-off – low water pressure in the boiler
F.23
Safety switch-off – temperature difference too great (NTC1/NTC2
F.24
Safety switch-off – temperature rise too fast
F.25
Safety switch-off – flue gas temperature too high
F.27
Safety switch-off – fault in flame detection
F.28
Ignition unsuccessful when starting up
F.29
Flame loss
F.32
Fan frost protection function active – fan speed outside the tolerance values
F.33
Fan frost protection function active – air pressure switch fault
FA9
eBUS fault – voltage too low
F.61
Gas valve control system fault
F.82
Gas valve switch-off control fault
F.83
EEPROM fault – electronics defective
F.64
Electronics/sensor/analogue-to-digital converter fault
F.85
Electronics temperature too high
F.67
Value sent back by ASIC is incorrect (flame slgnal)
F.88
Unstable flame (analogue input), underfloor heating contact or gas valve fault
F.70
Invalid product code (DSN)
F.71
Flow/return temperature sensor
F.72
Deviation in the water pressure sensor/return temperature sensor
F.73
Water pressure sensor not connected or has short-circuited
F.74
Electrical problem in the water pressure sensor
F.75
Pressure sensor fault
F.78
The safety cut-out in the primary heat exchanger is defective
F.77
Fault: Condensate or smoke
F.78
Interruption to domestic hot water (DHW) outlet sensor at external controller
F.83
Burner temperature sensor fault
F.84
Flow/return temperature sensor fault
F.85
Temperature sensor fault
F.87
Electrodes fault
F.89
Pump fault
Connection
No communication between the printed circuit board (PCB) and the user interface