BoilerFaultCodesThe 6 most common faults
Your boiler's internal computer chip has lost connection or failed to communicate with the main control board, preventing the system from starting.
Why it happens: This fault occurs when the main control board can no longer read the data from the small plug-in chip that tells the boiler exactly how to operate. The most common reason is that the chip has vibrated loose, or the electronic connection between the chip and the board has failed due to age or a power surge.
Turn the boiler power off at the fused spur switchWait for 30 secondsTurn the power back on and press the 'Reset' button
Your boiler has stopped working because the water pressure inside the system has dropped too low to operate safely.
Why it happens: This fault occurs when the water pressure inside your heating system drops below the minimum level required for the boiler to fire up. The most common reasons for this are a leak somewhere in your radiators and pipework, or the fact that you recently bled your radiators and haven't topped the water back up yet.
Locate the filling loop (usually a silver braided hose with small valves) underneath the boiler.Slowly open both taps until you hear water flowing and watch the pressure gauge.Close both taps tightly once the needle reaches between 1 and 1.5 bar.
Your boiler has started to fire up but the flame has gone out, meaning the system has shut down for safety.
Why it happens: This fault occurs when the boiler's control system detects that a flame was momentarily lit but couldn't be maintained, causing it to shut down for safety. The most common reasons are a lack of gas reaching the burner, a dirty internal sensor that cannot 'see' the flame, or a fault with the ignition components. It essentially means the boiler started to produce heat but lost its power source almost immediately.
Check that your gas supply is turned on at the meterIf you have a prepay meter, check that you have remaining creditReset the boiler by pressing the reset button or turning the control knob to 'reset' and back
Your boiler has become too hot or water is not moving through the system properly, causing the unit to shut down for safety.
Why it happens: This fault occurs when the water inside your boiler reaches a temperature that is too high for safe operation. It is usually caused by a blockage in the pipework or a mechanical failure in the pump, which prevents water from moving away from the heat source quickly enough. In some cases, a buildup of debris or sludge in the system can restrict flow and trigger this safety shutdown.
Check that your radiator valves are fully openEnsure your boiler pressure is between 1.0 and 1.5 barBleed your radiators to remove any trapped air
Your boiler has lost its flame while running or failed to light, meaning it has shut down for safety and won't provide heat or hot water.
Why it happens: This fault occurs when the boiler's control system cannot detect a steady flame, causing it to shut down for safety. It is often caused by a lack of fuel reaching the burner, a dirty internal component that sensors the heat, or a blockage in the pipe that carries away waste liquid.
Check that you have credit on your gas meter and that the external gas valve is open.If it is freezing outside, check if your white plastic condensate pipe is blocked with ice and thaw it with warm water.Hold the 'Reset' button for three seconds to restart the ignition sequence.
Your boiler has been manually reset too many times in a short window of time as it tries to clear a persistent underlying fault.
Why it happens: This fault occurs when the boiler is manually reset five times within a fifteen-minute window, causing the system to lock you out for safety. It is usually triggered because you are trying to clear a different, persistent error that hasn't been fixed, such as an ignition or flame failure. The boiler essentially stops responding to prevent potential damage from repeated failed start-up attempts.
Turn the power supply to the boiler off at the fused spur switchWait for 30 secondsTurn the power back on to clear the lockout memory
on the Ideal Logic+ Heat
Based on parts cited in our fault code database. Your engineer will confirm what's actually needed after diagnosis.
Call a Gas Safe engineer if…
- You can smell gas or see signs of a leak
- The Ideal shows an Emergency or High severity code
- The boiler keeps locking out after repeated resets
- You've tried the DIY checks and the fault hasn't cleared
- There's visible water leaking from the boiler
- The flame is yellow or orange instead of blue