An EA fault on a Worcester boiler usually appears after a power cut because the ignition sequence was interrupted mid cycle, leaving the gas valve, fan, or flame sensor out of sync. Most of the time, a single reset clears it. If it keeps coming back, the cause is often a faulty ignition lead, a dirty flame sensor, or low gas pressure rather than the power cut itself.
Why Power Cuts Trigger an EA Fault
If your boiler started displaying an EA fault right after the lights flickered or the power went out completely, you’ve run into one of the most common reasons homeowners contact an engineer about a Worcester EA fault code. This is a flame detection failure, and it almost always shows up at the worst possible moment, usually in the middle of winter when the heating is needed most.
Worcester boilers go through a set sequence every time they fire up. The fan spins, the gas valve opens, the spark ignites the burner, and a sensor checks that a flame is actually there.
When power cuts out mid sequence, the boiler can lose its place in that process. On restart, it sometimes tries to ignite before the fan has cleared the combustion chamber properly, or before gas pressure has stabilised, and the flame sensor doesn’t pick up a flame in time.
What Does the EA Fault Code Mean?
EA is Worcester’s code for an ignition or flame detection fault. The boiler attempted to light the burner but either failed to ignite, or the flame went out before the sensor confirmed it was lit. The boiler then locks out as a safety precaution.
Common Causes of EA After a Power Cut
1. Interrupted Ignition Sequence
This is the most common cause and usually the easiest to fix. The boiler’s electronics simply need to run through a clean start cycle.
A single reset, done correctly, restarts the whole sequence from the beginning and clears the fault in most cases.
2. Air in the Gas Line or System
Power cuts sometimes coincide with gas supply interruptions, especially during storms. Air can get trapped in the line, which delays ignition just long enough to trigger EA.
This usually clears itself after one or two reset attempts as the air works through, but it shouldn’t need more than that.
3. Dirty or Faulty Flame Sensor
The flame sensor (also called a flame rectification rod) sits in the burner and confirms a flame is present using a tiny electrical signal.
If it’s coated in soot or starting to fail, it may not detect a perfectly good flame. Power cuts don’t cause this fault directly, but they often expose a sensor that was already on its way out.
4. Worn Ignition Electrode or Lead
The spark electrode and its lead can degrade over time, especially in older boilers. A weak spark might just about manage ignition under normal conditions, but fail during the slightly different startup sequence after a power cut.
5. Low Gas or Water Pressure
If your system pressure or gas supply pressure was already borderline before the power cut, the extra demand of a cold restart can be enough to push the boiler into a flame detection fault.
How to Fix an EA Fault After a Power Cut
Most EA faults after a power cut can be cleared at home with a proper reset. Here’s the process most engineers recommend.
1. Wait two to three minutes after power returns before resetting, to let everything settle.
2. Press and hold the reset button on the boiler display until it restarts.
3. Watch the display through the full startup sequence rather than walking away.
4. If EA appears again, wait a few minutes and try one more reset.
5. If it fails a second time, stop resetting and book an engineer rather than repeating the cycle.
Quick Fix Summary
Reset once, wait, then reset again if needed. Two failed resets in a row usually means there’s an underlying fault, not just a startup hiccup, and repeated resetting won’t solve it.
Reset Attempts vs What They Tell You
| Outcome | What It Suggests | Next Step |
| Clears on first reset | Simple sequence interruption from the power cut | No further action needed |
| Clears on second reset | Possible air in the line or borderline pressure | Monitor over the next few days |
| Returns within minutes | Flame sensor or ignition electrode issue | Book an engineer |
| Won’t clear at all | Gas valve, PCB, or wiring fault | Book an engineer, avoid further resets |
Worcester Ignition Fault EA vs Other Common Fault Codes
It helps to know how EA compares to other codes you might see on a Worcester display, since the right fix depends on which one you’re dealing with.
| Code | Meaning | Common Trigger |
| EA | Ignition or flame detection fault | Power cut, dirty sensor, weak spark |
| E9 | Fan speed fault | Blocked flue or failing fan |
| D5 | PCB communication fault | Wiring or board issue, often after power loss |
| EE | Pressure sensor fault | Low system pressure |
A Worcester ignition fault ea is usually the first sign of a problem, but if you’re seeing other codes alongside it, that points to a wider issue worth flagging to your engineer.
How to Prevent EA Faults in the Future
• Have your boiler serviced annually, with the flame sensor cleaned as part of the check
• Keep system pressure between 1 and 1.5 bar, or as stated in your manual
• Avoid switching the boiler off completely during power cuts if you can help it, since a clean restart is gentler on the system
• Ask your engineer to check the ignition electrode and lead during the next service if your boiler is over 7 years old
When to Call a Heating Engineer
A single EA fault that clears after a reset is rarely a sign of anything serious. It’s the repeat faults you need to pay attention to.
• EA returns within minutes of a reset, more than once
• You notice a burning smell or unusual noise during startup
• Other Worcester boiler fault codes appear alongside EA
• The boiler is over 8 years old and faults are becoming more frequent
Worcester boiler fault codes like EA are designed to stop the boiler running unsafely, so repeated lockouts shouldn’t be ignored or reset away indefinitely.
Frequently Asked Questions
1. What does the Worcester EA error code mean?
The Worcester EA error code means the boiler failed to ignite properly or lost its flame signal during startup. It’s a safety lockout that stops the boiler until the fault clears or is repaired.
2. Why does my Worcester boiler show EA after every power cut?
If EA appears after every single power cut, the ignition components such as the flame sensor or electrode are likely already weak, and the power cut is simply the trigger that exposes the problem.
3. How many times can I reset an EA fault safely?
Two reset attempts is the general guideline. If EA returns a third time, stop resetting and get the boiler checked, since continued resets can mask a fault that needs proper attention.
4. Can low boiler pressure cause an EA fault?
Yes. If system pressure is too low, the boiler may struggle to maintain stable combustion during startup, which can trigger an EA flame detection fault, particularly after a cold restart.
5. Is an EA fault expensive to fix?
If the cause is a simple reset issue, there’s no cost at all. If it’s a flame sensor or ignition electrode, parts and labour are usually a modest call out fee, though costs vary by engineer and location.
6. Do all Worcester boilers use the EA code?
Most modern Worcester Bosch models, including the Greenstar range, use EA for ignition and flame detection faults. Older models may display a different code for the same underlying issue, so check your specific manual if unsure.
7. Can a power surge damage the boiler’s PCB and cause EA?
It’s possible but less common than a simple ignition sequence interruption. If EA is accompanied by other fault codes or the display behaves oddly, a PCB issue from a power surge becomes more likely and should be checked by an engineer.
Final Thoughts
An EA fault straight after a power cut is usually nothing more than a boiler that lost its place mid startup, and a careful reset sorts it out in most homes. The cases that need attention are the ones where the fault keeps returning, since that points to a component that was already struggling before the power even went out.
If you’ve tried resetting and the fault won’t clear, or it keeps coming back within minutes, it’s worth getting a Gas Safe engineer to take a look rather than leaving the boiler off in the cold. 0800 Homefix has engineers familiar with Worcester Bosch systems and can usually get someone out quickly to get the heating working safely again.
