A Worcester Bosch boiler showing EA has failed to confirm a flame when it expected one. On several Greenstar models, the display may alternate between EA and a three-digit cause code—commonly 227. The exact display and permitted user action depend on the model, so note every character and check the operating manual for your boiler.
EA is an ignition lockout, not a diagnosis of one particular broken part. A boiler can fail to establish or prove a flame for several reasons, including an interrupted gas supply, ignition or flame-sensing trouble, a condensate blockage, or another internal fault. Most of those require a Gas Safe registered engineer.
What does Worcester Bosch EA mean?
Worcester Bosch service literature describes EA as “flame not detected”. Modern boilers run a controlled ignition sequence and monitor whether a stable flame has formed. If the expected flame signal is absent, the boiler shuts down and displays a lockout rather than continuing to release gas.
That safety response is doing its job. The code tells an engineer where the operating sequence stopped, but it does not identify the failed component by itself. Model, service history, symptoms and test results all matter.
Is EA the same as 227?
They are closely related on many Worcester Bosch Greenstar boilers. Some displays show a broad letter code such as EA together with a more specific three-digit cause code such as 227. Worcester’s Greenstar Si Compact user instructions use EA and 227 as the example fault information to quote when seeking help.
Do not assume every Worcester model uses identical codes. Newer and older control systems can present faults differently. Photograph the display and find the manual using the full model name from the appliance—not just “Worcester boiler”.
Safe checks before arranging a repair
Check whether other gas appliances work
If you have another gas appliance that you normally use safely, such as a gas hob, check whether it has a supply. Do not repeatedly try to light it and do not use it as a test if you smell gas. If all gas appliances have stopped, check whether your prepayment meter has credit and ask your gas supplier whether there is an interruption.
Look at the boiler pressure
Check the pressure display while the system is cool. Use the range stated in your boiler manual; many sealed systems sit around 1 to 1.5 bar when cool, but your model and installation take priority. EA is primarily an ignition or flame-detection code, so changing the pressure unnecessarily will not cure it. If pressure is clearly too low or high, address that as a separate symptom.
Check the controls are actually asking for heat
Confirm the programmer is on, the thermostat target is above room temperature and the boiler has electrical power. These checks will not clear a genuine EA lockout, but they prevent a separate control issue from confusing the picture after a reset.
Check an external condensate pipe only from a safe position
Worcester Bosch says a blocked condensate pipe can be associated with repeated lockout, gurgling and an EA display. In freezing weather, inspect only the accessible outside section from ground level. Ice, a sagging pipe or an obvious obstruction may be relevant. Do not climb, dismantle boiler components or disconnect pipework.
If you are following manufacturer instructions to thaw an accessible frozen plastic condensate pipe, use warm—not boiling—water or another method specifically permitted by the manual. Stop if the pipe is damaged, inaccessible or near electrical equipment. A recurring freeze-up needs the installation checked for pipe size, route, fall and insulation rather than repeated thawing.
Try one reset exactly as the manual describes
Worcester user guides allow a normal user reset for some EA alerts. The method varies: one model may need a brief press, another may specify holding the reset control for several seconds. Follow your exact manual and try it once. If EA returns, the boiler is telling you the fault remains.
Repeatedly resetting an appliance is not a repair and can hide useful evidence. Write down whether the boiler clicks, fans, makes a short ignition attempt, gurgles or returns immediately to EA—but do not remove the case to investigate.
What can cause an EA ignition lockout?
No gas or inadequate gas supply
An exhausted prepayment meter, supplier interruption, closed control or a supply-pressure problem can prevent ignition. A householder can check meter credit and whether an existing gas hob works normally, but gas-pressure tests and work on valves or pipework belong to a suitably qualified Gas Safe engineer.
Ignition or flame-sensing fault
The ignition electrode, lead, flame-sensing arrangement, gas valve, electrical supply or control system may be involved. Worcester’s professional fault table lists several of these checks, but it explicitly presents them as competent-person fault finding. They are not homeowner repair steps.
Condensate or flue problem
A frozen or blocked condensate route can stop a condensing boiler operating correctly. Flue damage or obstruction can also affect safe operation. You may visually observe an external terminal from a safe location, but do not insert anything into it, dismantle it or attempt work at height.
Combustion setup or internal component issue
An engineer may need to test gas supply pressure, ignition, flame signal, combustion, condensate drainage and electrical components. Parts should not be replaced simply because an online list associates them with EA. Proper testing avoids unnecessary cost and confirms that the appliance is safe after repair.
When EA needs urgent action
An EA code without other warning signs normally means the boiler has safely locked out. However, leave the property and call the National Gas Emergency Service on 0800 111 999 if you smell gas or suspect carbon monoxide. Do not operate electrical switches, smoke or use a naked flame.
Carbon monoxide cannot be seen, smelled or tasted. Symptoms can include headache, dizziness, nausea, breathlessness, collapse or loss of consciousness. Move to fresh air and seek urgent medical help if exposure is suspected.
Can I repair Worcester EA myself?
No internal repair should be attempted. Do not remove the boiler casing, adjust gas controls, clean electrodes, bridge safety devices or follow installer fault-finding instructions. Gas Safe Register warns householders not to fit, fix or move gas appliances themselves.
The reasonable homeowner actions are limited to checking supplies and settings, observing accessible external pipework and performing the manual’s normal reset. Anything beyond that needs the right competence and test equipment.
What to tell the engineer
- The full boiler model and approximate age.
- Every code displayed, including EA and any three-digit number.
- Whether the fault affects heating, hot water or both.
- Whether other gas appliances operate normally.
- The system pressure when cool.
- Whether the boiler gurgles or the weather is freezing.
- Whether one manual reset worked temporarily.
- Recent servicing, building work or repeated previous lockouts.
This information helps the engineer arrive prepared, but they will still diagnose the fault rather than treating the code as proof that a particular part has failed.
Frequently asked questions
Will EA clear on its own?
A temporary supply interruption may pass, but a locked-out boiler generally needs the permitted reset before it tries again. If the code returns, arrange diagnosis.
Does EA always mean a frozen condensate pipe?
No. Worcester confirms that a condensate blockage can produce EA, particularly with gurgling or freezing conditions, but EA broadly means the flame was not detected. There are other possible causes.
How many times should I reset it?
Try one reset using the exact user manual. Do not keep resetting a boiler that repeatedly locks out.
Is EA covered by my Worcester guarantee?
Coverage depends on the appliance, registration, guarantee terms, service history and cause. A fault caused by installation, external systems or maintenance may be treated differently from a covered component failure. Check your documents before authorising chargeable work.
Can I use the boiler while EA is showing?
The boiler has locked out and will not operate normally. Do not bypass the lockout. Use safe alternative heating if required and arrange repair.
Related boiler help
Read how to reset a boiler safely, why condensate pipes freeze, safe checks when a boiler will not fire and what boiler pressure should be.
Worcester EA code still coming back?
Book a clear, fixed-price Worcester Bosch boiler repair visit with Incredaboil.