Worcester Bosch EA 227 Fault Code: What It Means & How to Fix It

By Mark White, Gas Safe Registered Engineer (638919) · 6 min read

If your Worcester Bosch is showing EA 227 (sometimes just EA, or 227 on its own), the short version is that the boiler tried to light, couldn't detect a flame, and locked itself out. It's the most common Worcester fault code by a distance, and a good share of the time the cause is outside the boiler and something you can check for free.

I'm a Gas Safe registered engineer based in Addlestone, and I repair Worcester Bosch boilers across Surrey every week. This guide covers what EA 227 means, the checks worth doing before you call anyone, and what's usually wrong when it keeps coming back.

What does EA 227 mean?

EA 227 is Worcester's ignition failure code. Each time the boiler fires, it opens the gas valve, sparks the ignition electrode, and then checks that a flame has actually formed. If it can't confirm a flame after its ignition attempts, it shuts the gas off and locks out. You'll see it on the Greenstar i, Si, CDi and Highflow ranges, and on the newer 2000, 4000 and 8000 Series.

Safe checks you can do yourself

1. Check you've got gas. Try the hob, if you have a gas one. If that won't light either, the problem is your supply, not the boiler. On a prepayment meter, check the credit and the emergency credit. Check the handle on the gas meter is in line with the pipe, which means on. If nothing gas in the house works and you've got credit, contact your gas supplier.

2. In freezing weather, check the condensate pipe. This is the big one in winter. Your boiler drains acidic water through a plastic pipe, usually white or grey, that runs outside to a drain. When it freezes, the water backs up into the boiler and it stops firing. Worcester's own advice is that a frozen condensate pipe can show as an EA fault. If it's been below freezing and the boiler is gurgling, follow the pipe outside, find the frozen section (often at a bend or the open end) and pour warm, not boiling, water along it. Boiling water can crack the pipe. A hot water bottle or a heat wrap works too.

3. Reset once. Press the reset button (on some models you hold it for a few seconds; your manual shows which). If it lights and runs normally, the cause was probably the gas supply or a frozen pipe. If EA 227 comes straight back, stop resetting and call an engineer.

That's the full list of safe DIY checks. Everything else, including the electrode, gas valve and flue, is sealed-case work that needs a Gas Safe registered engineer.

Why EA 227 keeps coming back

If the gas is on and the condensate isn't frozen, the cause is almost always inside the boiler:

A worn ignition or flame sensing electrode. This is the most common cause I find. Electrodes erode over time, and on older Greenstar models it's practically a service item. The boiler sparks, the flame lights, but the electrode can't sense it, so the boiler assumes it failed.

A blocked condensate trap or siphon. Even in summer, sludge can build up in the trap inside the boiler and cause the same symptoms as a frozen pipe. Cleaning it is part of a proper annual service.

A gas valve or gas pressure problem. If the gas valve isn't opening properly, or the pressure reaching the boiler is too low (an undersized pipe or a failing meter regulator, say), the flame either won't form or won't hold.

Ignition lead or control board faults. These are less common, but cracked leads and failing boards both turn up, especially on boilers that have had water damage.

What I do on an EA 227 callout

I test before replacing anything: working gas pressure at the meter and the boiler, the condition and gap of the electrode, the ignition lead, the condensate trap and pipe run, the gas valve operation and a flue gas analysis. I carry Worcester ignition parts on the van, so most EA 227 repairs are done the same day.

There's a diagnostic fee that's included in the repair cost if you go ahead, and you'll always get a clear price before any work starts.

Stopping it happening every winter

If your condensate pipe freezes most winters, it's usually because it runs a long way outside in a narrow pipe with no insulation. Current guidance is for external condensate runs to be in wider pipe and kept as short as possible, and insulating the outside section helps a lot. I can reroute, upsize or insulate it, often while I'm there for a service.

Related Worcester fault codes

E9 224 is an overheat lockout (often circulation or sludge) and CE 207 is low water pressure, so top it up to about 1.2 bar with the filling loop. I've covered more codes on my Worcester Bosch repairs page. If you've got a Baxi, the same frozen condensate problem shows as E133.

Frequently asked questions

Check the gas supply and, in freezing weather, the condensate pipe first. Then press the reset button once (some models need it held for a few seconds). If EA 227 returns, don't keep resetting. Get it diagnosed.

Yes. It's one of the most common causes in cold weather. Thaw the outside section with warm (not boiling) water, then reset the boiler once.

It depends on the cause. A thawed pipe costs nothing, and an electrode is a fairly inexpensive part. A gas valve or control board costs more. I charge a diagnostic fee that's included in the repair if you go ahead, and you get a clear price before any work starts.

The lockout itself is the boiler keeping you safe: it shuts the gas off when it can't confirm a flame. But if you ever smell gas, turn it off at the meter if you can do so safely, open the windows, don't use electrical switches, and call the National Gas Emergency line on 0800 111 999 straight away.

Worcester showing EA 227 in Surrey?

I repair Worcester Bosch boilers across Addlestone, Weybridge, Chertsey, Walton-on-Thames, Byfleet, Woking, Shepperton and the surrounding areas. Call me on 07311 811574 and I'll usually get to you the same or next day, or send me the fault details if you can't talk right now.

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