Ideal Turbo2 24 Fault codes & diagnostics

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

Combi Natural Gas 24 kW 1993-1996 Discontinued

Replaced by: Logic Plus Combi

The fault code is already on your display

Note it down before pressing reset — resetting clears the code immediately. How to read fault codes →

Severity at a glance

Each cell = one fault code. Hover to identify.
8 High 8 Low
Just want the most common Ideal Turbo2 24 faults?
The top 6 problems in plain English — with causes, DIY checks and repair costs.
Fault codes

All 16 documented codes

Tap any card for details

Air Pressure O.K.

Your boiler is successfully starting a pilot flame, but it is failing to transition to the main burner to provide heat or hot water.

High Engineer only £120-280

Parts commonly replaced

  • Main Gas Valve
  • Control Box
  • Solenoid Coil
Full explanation for Air Pressure O.K.
Condensate Drain Blockage

Liquid waste produced by the boiler is not draining away properly, which has caused the system to switch itself off for safety.

High DIY-safe £90-160

What to check first

  1. Check the white plastic pipe exiting the boiler to see if it is blocked or disconnected.
  2. If the pipe runs outside, check if the end of the pipe is frozen and pour warm (not boiling) water over it to melt the ice.
  3. Ensure the internal condensate trap is not full of debris and can be cleared if accessible without opening the sealed boiler casing.

Parts commonly replaced

  • Condensate trap
  • Condensate pipework
  • Internal siphon
Full explanation for Condensate Drain Blockage
Flue gas overheat

Your boiler has switched itself off because the internal gases have become too hot, which could damage the heat exchanger or seals.

High Engineer only £150-£650

Parts commonly replaced

  • Flue Gas Overheat Thermostat
  • Main Heat Exchanger
  • Thermistor
Full explanation for Flue gas overheat
FLUE OVERHEAT THERMOSTAT

Your boiler has shut down because the exhaust gases have become too hot, which is a safety measure to prevent damage or dangerous fumes.

High Engineer only £120-£350

Parts commonly replaced

  • Flue Overheat Thermostat
  • Main Heat Exchanger
  • Gas Valve (Calibration)
Full explanation for FLUE OVERHEAT THERMOSTAT
Overheat

Your boiler has become too hot and has automatically shut down to prevent damage or safety issues.

High DIY-safe £100-280

What to check first

  1. Check that all radiator valves are open to ensure water can flow through the system.
  2. Wait for the boiler to cool down completely.
  3. Press the reset button once to see if the overheat light clears.

Parts commonly replaced

  • Overheat Thermostat
  • Circulation Pump
  • Control Thermostat
Full explanation for Overheat
OVERHEAT NEON

Your boiler has switched itself off because it has become too hot to operate safely.

High DIY-safe £120-280

What to check first

  1. Ensure all radiator valves are fully open
  2. Allow the boiler to cool down for at least 30 minutes
  3. Locate the reset button on the control panel and press it firmly

Parts commonly replaced

  • Circulation pump
  • Overheat thermostat
  • Main heat exchanger (flushing)
Full explanation for OVERHEAT NEON
Power On

Your boiler is receiving electrical power and is switched on, which is normal operating behavior.

Low DIY-safe

What to check first

  1. Check that the main power switch is in the 'ON' position
  2. Ensure your thermostat is calling for heat if you want the boiler to fire up
  3. Verify that the timer or programmer is set to an 'ON' period
Full explanation for Power On
SUMP FAN FAILURE THERMOSTAT

Your boiler has detected that a safety sensor near the fan or collection area has triggered because it has become too hot or has detected a block.

High Engineer only £140-£280

Parts commonly replaced

  • Sump/Fan Thermostat
  • Main Fan Assembly
  • Venturi Tube
Full explanation for SUMP FAN FAILURE THERMOSTAT
WATER OVERHEAT THERMOSTAT

Your boiler has switched itself off because it got too hot and needs a chance to cool down before it can restart safely.

High DIY-safe £90-250

What to check first

  1. Check that all radiator valves are fully open
  2. Allow the boiler to cool down for at least 20 minutes
  3. Press the reset button on the front of the control panel

Parts commonly replaced

  • Overheat Thermostat
  • Circulation Pump
  • Thermistor
Full explanation for WATER OVERHEAT THERMOSTAT