Glow-worm Betacom2 24 Fault codes & diagnostics

33 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.

Gas 2012-present
GC Number 47-019-16
Download the Glow-worm Betacom2 24 manualThe official installation and service manual (PDF), the document these fault codes were read from. PDF

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Severity at a glance

Each cell = one fault code. Hover to identify.
4 Emergency 28 High 1 Medium

Which version do you have?

The GC number on your boiler's data badge identifies the exact appliance and production years, as recorded in the UK Product Characteristics Database.

GC number Appliance (register name) Produced
47-019-16 Betacom2 24 2012–present

Appliance names and production years are taken from the UK Product Characteristics Database (the SAP/SEDBUK register). Where a GC number is also printed in this model's own manufacturer manual, both sources were checked to agree.

All 33 documented codes

Tap any card for details

Err

Your boiler's control panel has developed a fault and can no longer communicate with the internal system, meaning you cannot change settings or operate the unit.

High Engineer only £180-£320

Parts commonly replaced

  • User Interface Board
  • Main PCB (Printed Circuit Board)
  • Display Ribbon Cable

Related codes

F00

Your boiler has lost the ability to accurately measure the temperature of the water circulating through your heating system, so it has shut down to prevent damage.

High Engineer only £120-200

Parts commonly replaced

  • Flow temperature sensor (NTC thermistor)
  • Wiring harness

Related codes

F01

Your boiler has stopped working because a sensor that monitors the temperature of the water returning to the system is reading incorrectly or has disconnected.

High Engineer only £120-200

Parts commonly replaced

  • Return NTC thermistor
  • Wiring harness
F10

Your boiler's temperature sensor is providing faulty readings, so it has safely shut down to prevent overheating.

High Engineer only £120-220

Parts commonly replaced

  • Flow temperature sensor (NTC thermistor)
  • Wiring harness

Related codes

F11

Your boiler is struggling to accurately measure the temperature of the water returning to it, so it has stopped working to prevent potential overheating.

High Engineer only £120-200

Parts commonly replaced

  • Return NTC thermistor
  • Wiring harness

Related codes

F20

Your boiler has detected that it is running too hot and has automatically shut down to prevent damage to its internal components.

High Engineer only £120-250

Parts commonly replaced

  • NTC thermistor sensor
  • Central heating pump
  • Heat exchanger

Related codes

F22

Your boiler has stopped working because the water pressure inside the system has dropped too low to operate safely.

High DIY-safe £80-150

What to check first

  1. Locate the filling loop, which is a silver braided hose with one or two valves located underneath your boiler.
  2. Gradually open the valve(s) to let water into the system until the pressure gauge on the front of the boiler reads between 1.0 and 1.5 bar.
  3. Close the valve(s) tightly to ensure no water continues to leak into the system.

Parts commonly replaced

  • Filling loop
  • Pressure relief valve
  • Expansion vessel

Related codes

F23

Your boiler has shut down because the water leaving the boiler is getting much hotter than the water returning, usually pointing to a blockage or a pump issue.

High Engineer only £150-350

Parts commonly replaced

  • Central heating pump
  • Plate heat exchanger
  • Automatic bypass valve

Related codes

F24

Your boiler is struggling to pump water around your heating system correctly, which is likely due to low system pressure or a blockage.

High DIY-safe £100-250

What to check first

  1. Check your boiler's pressure gauge and ensure it is between 1 and 1.5 bar.
  2. If the pressure is below 1 bar, use the filling loop underneath the boiler to top it up to the recommended level.
  3. Restart your boiler and check if the fault clears.

Parts commonly replaced

  • Central heating pump
  • Pressure sensor
  • Bypass valve

Related codes

F26

Your boiler has detected a problem with the internal part that controls the flow of gas, which is preventing it from lighting safely.

High Engineer only £200-£350

Parts commonly replaced

  • Gas valve
  • Wiring harness

Related codes

Showing 11–20 of 33
F27

Your boiler has stopped working because it cannot confirm that the flame is staying lit safely.

High Engineer only £120-£350

Parts commonly replaced

  • Flame sensing electrode
  • Ignition lead
  • Gas valve
  • Printed Circuit Board (PCB)

Related codes

F28

Your boiler has stopped working because it cannot successfully start up its flame to heat your home.

High Engineer only £150-300

Parts commonly replaced

  • Electrodes
  • Gas valve
  • Printed Circuit Board (PCB)

Related codes

F29

Your boiler was working but the flame has unexpectedly gone out, causing the system to stop for safety.

High DIY-safe £100-£350

What to check first

  1. Check if other gas appliances in your home, like a hob, are working to confirm gas supply.
  2. If it is freezing outside, check if the white plastic condensate pipe leading outdoors is frozen and thaw it with warm water.
  3. Press the reset button (flame symbol with a cross) for five seconds to restart the boiler.

Parts commonly replaced

  • Ignition Electrode
  • Gas Valve
  • Spark Generator

Related codes

F32

Your boiler is struggling to push air through its exhaust system, which prevents it from firing up safely to provide heating or hot water.

High Engineer only £150-300

Parts commonly replaced

  • Fan
  • Air pressure switch
  • Flue assembly

Related codes

F49

Your boiler is struggling to communicate with its internal controls or external thermostat due to an electrical connection issue.

High Engineer only £120-250

Parts commonly replaced

  • Main PCB
  • Wiring harness
  • External thermostat/controller

Related codes

F61

Your boiler has detected an issue with the electrical signal sent to the gas valve, meaning it cannot safely control the gas supply and has stopped working.

Emergency Engineer only £150-350

Parts commonly replaced

  • Gas valve
  • Printed Circuit Board (PCB)
  • Wiring harness

Related codes

F62

Your boiler has detected an issue with the valve that controls the gas supply and has safely shut itself down to prevent any risk.

Emergency Engineer only £150-300

Parts commonly replaced

  • Gas valve
  • Printed Circuit Board (PCB)

Related codes

F63

Your boiler's computer is having trouble reading its internal software, which has caused it to stop working completely to prevent further errors.

High Engineer only £250-450

Parts commonly replaced

  • Main PCB (Printed Circuit Board)

Related codes

F64

Your boiler's internal computer has encountered a serious internal error and can no longer control the system, meaning your heating and hot water will not work.

High Engineer only £250-450

Parts commonly replaced

  • Main Printed Circuit Board (PCB)

Related codes

F65

Your boiler has detected that its internal control electronics are overheating and has shut itself down to prevent damage.

High Engineer only £250-450

Parts commonly replaced

  • Main PCB
  • Wiring harness

Related codes

Showing 21–30 of 33
F67

Your boiler is failing to detect the flame correctly, so it has safely shut itself down to prevent any risk.

High Engineer only £250-450

Parts commonly replaced

  • Main Printed Circuit Board (PCB)
  • Flame detection electrode

Related codes

F68

Your boiler is failing to detect a stable flame, which usually points to an issue with the gas supply or ignition system.

High Engineer only £150-300

Parts commonly replaced

  • Ignition electrode
  • Gas valve
  • Main PCB

Related codes

F70

Your boiler's internal computer brain and display screen are struggling to talk to each other because they don't recognise each other's security settings.

High Engineer only £100-350

Parts commonly replaced

  • Main Printed Circuit Board
  • User Interface Panel

Related codes

F71

Your boiler has temporarily stopped working because it cannot accurately read the temperature of the water flowing through the system.

High Engineer only £100-£200

Parts commonly replaced

  • Flow temperature sensor
  • Sensor retaining clip

Related codes

F72

Your boiler has detected that its temperature sensors are giving inconsistent readings, suggesting they are either faulty or out of sync.

High Engineer only £100-£180

Parts commonly replaced

  • Flow NTC sensor
  • Return NTC sensor
  • Primary Heat Exchanger (if blocked)

Related codes

F73

Your boiler is struggling to read its own internal water pressure, which means it has shut down as a safety precaution.

High Engineer only £140-£220

Parts commonly replaced

  • Water pressure sensor
  • Wiring harness

Related codes

F74

Your boiler's internal sensor is struggling to accurately measure the water pressure, causing the system to shut down as a safety precaution.

High Engineer only £120-£200

Parts commonly replaced

  • Water pressure sensor
  • Wiring harness

Related codes

F76

Your boiler has detected a break in a safety circuit designed to shut the system down if it gets too hot.

Emergency Engineer only £100-250

Parts commonly replaced

  • Thermal fuse
  • Overheat thermostat
  • Wiring harness

Related codes

F77

Your boiler has detected a safety issue with the internal gas control system and has shut down to protect your home.

Emergency Engineer only £200-£400

Parts commonly replaced

  • Gas valve
  • Wiring harness
  • Printed Circuit Board (PCB)

Related codes

F83

Your boiler has detected that there is not enough water inside the system, or the water isn't circulating properly to heat up when the burner turns on.

High Engineer only £120-250

Parts commonly replaced

  • Water pressure sensor
  • Circulating pump
  • Isolation valves

Related codes

Showing 31–33 of 33
F84

Your boiler has stopped working because its internal sensors are reporting conflicting temperature readings as if they have been swapped or disconnected.

High Engineer only £100-220

Parts commonly replaced

  • Flow temperature sensor
  • Return temperature sensor
  • Wiring harness

Related codes

F85

Your boiler has sensed that its tempature monitors are not correctly tracking the water flow, preventing it from heating up safely.

High Engineer only £90-180

Parts commonly replaced

  • Flow NTC sensor
  • Return NTC sensor
  • Wiring harness

Related codes

F86

Your boiler has detected an issue with the sensor or connection for an underfloor heating system, causing it to temporarily lock out to keep your home safe.

Medium Engineer only £90-180

Parts commonly replaced

  • Underfloor heating safety thermostat
  • Wiring harness
  • Temperature sensor

Related codes

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