Ideal Logic+ Combi 24 Fault codes & diagnostics

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

Combi Natural Gas 2009-2016 Discontinued
GC Number 47-348-65
Download the Ideal Logic+ Combi 24 manualThe official installation and service manual (PDF), the document these fault codes were read from. PDF

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9 High 1 Low
Fault codes

All 10 documented codes

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80

Your boiler has stopped working because the water pressure inside the system is too low or water isn't flowing through properly.

High DIY-safe

What to check first

  1. Check the pressure gauge on the front of the boiler to see if it is below 1.0 bar.
  2. Use the filling loop underneath the boiler to top the pressure back up to between 1.0 and 1.5 bar.
  3. Press the reset button on the boiler once the pressure is correct.

Parts commonly replaced

  • Pressure relief valve
  • Automatic air vent
  • Water pressure sensor

Related codes

Full explanation for 80
81

Your boiler has temporarily stopped working because it has detected a flame when there shouldn't be one, which is a safety lockout requiring a professional reset.

High Engineer only £150-£300

Parts commonly replaced

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

Related codes

Full explanation for 81
82

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

High DIY-safe

What to check first

  1. Locate the filling loop valves underneath your boiler.
  2. Open the valves gently to let water in until the pressure gauge reads between 1.0 and 1.5 bar.
  3. Close both valves firmly and press the reset button on your boiler.

Parts commonly replaced

  • Filling loop
  • Pressure relief valve
  • Pressure sensor

Related codes

Full explanation for 82
83

Your boiler has suddenly gone out because it lost the flame, meaning you currently have no heating or hot water.

High Engineer only £100-250

Parts commonly replaced

  • Ignition Lead
  • Electrode Assembly
  • Gas Valve

Related codes

Full explanation for 83
84

Your boiler has detected an issue with the internal fan that safely removes combustion gases, so it has shut down to prevent any risk.

High Engineer only £150-300

Parts commonly replaced

  • Fan assembly
  • Air pressure switch
  • Main printed circuit board (PCB)

Related codes

Full explanation for 84
85

Your boiler has detected a problem with the sensor that measures water temperature, so it has safely shut down to prevent overheating.

High Engineer only £90-£180

Parts commonly replaced

  • Flow thermistor
  • NTC sensor

Related codes

Full explanation for 85
86

Your boiler has temporarily stopped working because it has detected an issue with the sensor that measures the temperature of the water returning from your radiators.

High Engineer only £90-170

Parts commonly replaced

  • Return Thermistor
  • Wiring Harness

Related codes

Full explanation for 86
87

Your boiler is having trouble communicating with the outdoor weather sensor, though your heating and hot water should still continue to work normally.

Low Engineer only £90-180

Parts commonly replaced

  • Outside weather sensor
  • Sensor wiring

Related codes

Full explanation for 87
88

Your boiler has detected an issue with the sensor that measures hot water flow, meaning you likely have no hot water working properly.

High Engineer only £100-200

Parts commonly replaced

  • DHW Thermistor
  • Wiring Harness

Related codes

Full explanation for 88
89

Your boiler's main control computer is experiencing a communication error with its internal memory card, meaning it cannot safely operate until it is reset or repaired.

High Engineer only £150-300

Parts commonly replaced

  • PCB
  • Display PCB

Related codes

Full explanation for 89