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Glow-worm fault codes — in plain English.
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Glow-worm · Energy
- Glow-worm F.20Safety switch-off: the overheating temperature has been reached.
- Glow-worm F.22Safety switch-off: low water pressure in the boiler.
- Glow-worm F.23Safety switch-off: the temperature difference between sensors NTC1 and NTC2 is too great.
- Glow-worm F.24Safety switch-off: the temperature is rising too quickly.
- Glow-worm F.28The boiler was unable to ignite successfully when starting.
- Glow-worm F.29The flame has been lost.
- Glow-worm F.49eBUS fault: Voltage too low.
- Glow-worm F.64Fault: Electronics / sensor / analogue-to-digital converter.
- Glow-worm F.65Fault: Electronics temperature too high.
- Glow-worm F.00Fault: Flow temperature sensor.
- Glow-worm F.01Fault: Return temperature sensor.
- Glow-worm F.10Short circuit: Flow temperature sensor.
- Glow-worm F.11Short circuit: Return temperature sensor.
- Glow-worm F.63Fault: EEPROM.
- Glow-worm F.73Fault: Water pressure sensor not connected or short-circuited.
- Glow-worm F.75F.75 indicates a pressure sensor fault.
Glow-worm · Ultracom2 cxi 24/30/35
- Glow-worm F65Excessive main board temperature.
- Glow-worm F83No water in the installation: the temperature does not increase when the burner is lit.
- Glow-worm F84Permanent temperature difference between flow and return heating sensors (inverted, disconnected or defective sensors).
- Glow-worm F85Flow and return heating sensors fault (both sensors connected to the same pipe).
- Glow-worm F86Underfloor heating contact fault.
- Glow-worm F00Flow heating temperature sensor fault (open circuit).
- Glow-worm F01Return heating temperature sensor fault (disconnected).
- Glow-worm F10Flow heating temperature sensor fault (short-circuit).
- Glow-worm F11Return heating temperature sensor fault (short-circuit).
- Glow-worm F20Overheating fault — safety device activated (97°C).
- Glow-worm F23Max temperature difference return/flow — water circulation fault.
- Glow-worm F24Water circulation fault — pump malfunction (rapid temp rise).
- Glow-worm F49EBUS voltage fault (EBUS line / connector short).
- Glow-worm F63Fault in the main board memory.
- Glow-worm F64Fault in the main board — rapid flow/return sensor fluctuation.
- Glow-worm F71Flow heating temperature sensor fault (unclipped/defective).
- Glow-worm F72Permanent temperature difference between flow and return sensors.
- Glow-worm F73Heating circuit pressure sensor fault (shorted/disconnected).
- Glow-worm F74Heating circuit pressure sensor fault.
- Glow-worm F76Thermal fuse fault (disconnected or defective).
- Glow-worm F22F22 indicates low water pressure in the installation.
- Glow-worm F28F28 indicates an ignition fault.
- Glow-worm F29F29 indicates loss of flame during operation.
Glow-worm · Betacom 4 Combi
- Glow-worm F.23Safety shutdown: Temperature spread too great (NTC1/NTC2). Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.24Safety shutdown: Temperature rise too fast. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.64Fault: Electronics/sensor/analogue-to-digital converter. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.65Fault: Electronics temperature too high. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.71Fault: Flow/return temperature sensor. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.72Fault: Deviation in the water pressure sensor/return temperature sensor. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.74Fault: Electrical problem in the water pressure sensor. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.84Fault: Flow/return temperature sensor. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.85Fault: Temperature sensor. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.00Fault: Flow temperature sensor. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.01Fault: Return temperature sensor. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.20Safety shutdown: Overheating temperature reached. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.22Safety shutdown: Water deficiency in the boiler. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.83Fault: Dry fire. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.25Safety shutdown: Flue gas temperature too high. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.27Safety shutdown: Fault in flame detection (listed causes include a leaking gas solenoid valve). Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.28Fault: Ignition unsuccessful when starting up. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.29Fault: Flame loss (listed causes include gas supply temporarily stopped and flue gas recirculation). Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.61Fault: Gas valve assembly control. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.62Fault: Gas valve switch-off control (listed causes include delayed extinguishing of the flame signal and a leaking gas valve assembly). Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.10Short circuit: Flow temperature sensor. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.11Short circuit: Return temperature sensor. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.49eBUS fault: Voltage too low. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.63Fault: EEPROM. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.73Fault: Water pressure sensor not connected or has short-circuited. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.75Fault: Pressure sensor. Since the code table is used for various products, some codes may not be visible for the product in question.
Glow-worm · Easicom 3 Combi
- Glow-worm F.65Fault: Electronics temperature too high. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.71Fault: Flow/return temperature sensor. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.72Fault: Deviation in the water pressure sensor/return temperature sensor. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.84Fault: Flow/return temperature sensor. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.85Fault: Temperature sensor. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.00Fault: Flow temperature sensor. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.01Fault: Return temperature sensor. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.20Safety shutdown: Overheating temperature reached. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.22Safety shutdown: Water deficiency in the boiler. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.23Safety shutdown: Temperature spread too great (NTC1/NTC2). Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.24Safety shutdown: Temperature rise too fast. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.83Fault: Dry fire. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.25Safety shutdown: Flue gas temperature too high. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.27Safety shutdown: Fault in flame detection (listed causes include a leaking gas solenoid valve). Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.28Fault: Ignition unsuccessful when starting up. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.29Fault: Flame loss (listed causes include gas supply temporarily stopped and flue gas recirculation). Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.61Fault: Gas valve assembly control. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.62Fault: Gas valve switch-off control (listed causes include delayed extinguishing of the flame signal and a leaking gas valve assembly). Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.10Short circuit: Flow temperature sensor. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.11Short circuit: Return temperature sensor. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.49eBUS fault: Voltage too low. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.63Fault: EEPROM. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.64Fault: Electronics / sensor / analogue-to-digital converter. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.73Fault: Water pressure sensor not connected or has short-circuited. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.74Fault: Electrical problem in the water pressure sensor. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.75Fault: Pressure sensor. Since the code table is used for various products, some codes may not be visible for the product in question.
Glow-worm · Ultimate 3 Combi
- Glow-worm F.00Fault: Flow temperature sensor. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.01Fault: Return temperature sensor. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.10Short circuit: Flow temperature sensor. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.11Short circuit: Return temperature sensor. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.22Safety shutdown: Water deficiency in the boiler. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.49eBUS fault: Voltage too low. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.63Fault: EEPROM. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.64Fault: Electronics / sensor / analogue-to-digital converter. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.65Fault: Electronics temperature too high. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.71Fault: Flow/return temperature sensor. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.72Fault: Deviation in the water pressure sensor/return temperature sensor. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.73Fault: Water pressure sensor not connected or has short-circuited. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.74Fault: Electrical problem in the water pressure sensor. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.75Fault: Pressure sensor. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.84Fault: Flow/return temperature sensor. Since the code table is used for various products, some codes may not be visible for the product in question.
- Glow-worm F.85Fault: Temperature sensor. Since the code table is used for various products, some codes may not be visible for the product in question.
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Enter the code as it appears on your Glow-worm boiler display. We show published, verified entries for the matching range.