BoilerFaultCodesThe 6 most common faults
01
b 26 High DIY-safe
Your boiler has stopped working because the water pressure inside the system is currently too low to operate safely.
What to try first
Locate the filling loop (usually a silver braided hose under the boiler).Slowly open the valves on the filling loop to allow water into the system.Monitor the pressure gauge on the front of the boiler until it reaches 1.5 bar, then securely close the valves.
02
E36 High Engineer
Your boiler has detected an internal communication error between its main parts, causing it to shut down for safety until the connection is restored.
Full guide for E3603
36 High Engineer
Your boiler has lost its flame signal during operation, meaning it cannot maintain the heat required to provide you with hot water or central heating.
Full guide for 3604
U 1.2 High Engineer
Your boiler has stopped working because a small protective device inside the electrical system has failed, cutting off the power needed to operate the internal controls.
Full guide for U 1.205
E 00 High Engineer
Your boiler is failing to light the internal flame needed to produce heat and hot water despite several attempts.
Full guide for E 0006
E 02 High Engineer
Your boiler has failed to light the flame properly after a series of attempts and has shut down for safety reasons.
Full guide for E 02on the Ideal Imax W
Pressure sensorFilling loopCU control boardWiring harnessIgnition electrodeFlame rectification probe
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