Worcester Bosch EA Fault Code
The boiler has failed to detect a flame during ignition (flame detection failure) and has locked out for safety.
General guidance only — not a substitute for professional advice. Any gas work must be carried out by a Gas Safe registered engineer. If you smell gas or suspect carbon monoxide, leave the property and call the National Gas Emergency line on 0800 111 999.
What does the Worcester Bosch EA fault code mean?
The boiler has failed to detect a flame during ignition (flame detection failure) and has locked out for safety.
Common causes
- Gas supply interruption Common
No or low gas reaching the boiler — a prepay meter out of credit, an external gas isolation valve left off after maintenance, or low mains gas pressure.
- Frozen condensate pipe Common
In freezing weather the external condensate pipe can block with ice, causing the boiler to lock out. One of the most common winter causes.
- Faulty ignition electrode or flame sensor Sometimes
A worn or dirty ignition electrode/flame-sensing probe may fail to detect the flame even when the boiler lights.
- Faulty gas valve or PCB Rare
A failing gas valve or printed circuit board can prevent reliable ignition. Usually the most expensive cause to repair.
How to fix it
- Check your gas supply is on. DIY safe
Make sure other gas appliances (e.g. a hob) work. If you're on a prepayment meter, check there's credit, and confirm the gas isolation valve under the boiler is open.
- Check the condensate pipe for ice in cold weather. DIY safe
If the external white pipe is frozen, pour warm — not boiling — water over it to thaw the blockage.
- Reset the boiler. DIY safe
Hold the reset button for a few seconds and wait for the boiler to attempt ignition. Do not reset more than 2–3 times — repeated resets can mask a real fault.
- Call a Gas Safe registered engineer. Gas Safe engineer
If the EA code returns after the checks above, the ignition electrode, flame sensor, gas valve or PCB likely needs inspection. These are gas components and must only be handled by a Gas Safe engineer.
Parts you may need
- Ignition electrode · from £25
- Flame sensor · from £30
- Gas valve · from £150
The exact spare depends on your boiler's GC number (on the data badge). Check this against the part before buying.
Typical repair cost
Expect to pay roughly £80–£500, depending on the underlying cause.
Frequently asked questions
Can I fix a Worcester Bosch EA fault myself?
You can safely carry out the basic checks — gas supply, frozen condensate pipe, and a reset. If the fault persists it points to a gas component (electrode, sensor, gas valve or PCB), which must be repaired by a Gas Safe registered engineer.
How much does it cost to fix a Worcester Bosch EA fault?
Repairs typically range from £80 to £500. A frozen condensate pipe costs nothing to thaw, while gas valve or PCB replacements are at the higher end.
Is it safe to keep resetting an EA fault?
No. Resetting 2–3 times is fine, but repeatedly resetting a boiler that keeps locking out can hide a genuine safety fault. If EA keeps returning, stop and call an engineer.