How to Fix Worcester Bosch Fault 227

What the Worcester fault 227 code means

Fault 227 means your Worcester Bosch boiler tried to fire up but couldn't detect a flame. It usually attempts ignition four or five times. If it still can't sense a flame, it locks out and shuts down on safety. The same fault sometimes shows as EA 227.

A lockout is the boiler protecting itself. It is not the cause of the problem, just the symptom. The job is to find why no flame is being detected.

What causes fault 227?

There are a handful of common causes. Some you can check yourself. Most need a Gas Safe engineer.

Faulty or misadjusted gas valve

This is the most common cause. If the gas valve is faulty or set wrong, the boiler can't light properly. An engineer will check whether it needs adjusting or replacing.

Frozen condensate pipe

In cold weather this is the usual culprit, and you can often clear it yourself. Pour warm (not boiling) water over the external pipe to thaw it, then reset the boiler. If it fires up and stays on, that was the problem.

Frozen gas meter

If 227 keeps coming back in freezing weather, an external gas meter can partially freeze and disrupt the gas supply. Check whether the meter is insulated. An engineer can advise on lagging it properly.

Blocked pilot jet

A small amount of dirt can block the jet and stop the flame forming. If the flame flickered before going out, this may be it. An engineer can clean it.

Damaged electrode or ignition lead

The electrode and ignition lead have to be in good condition to strike a flame. If they're worn or damaged, the boiler won't light. They can sometimes be cleaned, but often it's cheaper to replace them

Internal leak onto the PCB

Even a small internal leak can drip onto electrical parts. A leaking heat exchanger is hard to spot from the outside. If moisture reaches the PCB (the boiler's control board), it can fail. If you see fault 227 alongside a leak, turn off the boiler and the water supply, then call an engineer. PCB-related repairs can be expensive, so an engineer should confirm the fault and provide a quote before any repair is approved.

If your boiler is over 10 years old and needs a significant repair, it may be worth comparing the repair quote against a replacement quote rather than assuming repair is always the best option. Serviceteam is an authorised Worcester Bosch installer in London.

What you can check before calling an engineer

Anything beyond these basic checks should be left to a Gas Safe engineer. Don't attempt gas or ignition work yourself.

1. Check the boiler pressure gauge. It should sit between roughly 1 and 2 bar.
2. Look at the external condensate pipe for ice in cold weather, and thaw it with warm water if frozen.
3. Reset the boiler once, following the steps in your manual.

If a single reset doesn't hold, or the fault returns, stop there and book an engineer.

Common mistakes to avoid

A few things make 227 worse or hide the real fault:

• Resetting the boiler repeatedly instead of fixing the cause.
• Ignoring low pressure rather than topping it up and checking for leaks.
• Leaving an exposed condensate pipe unlagged so it freezes again.

Annual servicing by a Gas Safe engineer catches most of these before they cause a lockout.

When to call a Gas Safe engineer

When a Worcester boiler throws fault 227 and shuts down, something is stopping it lighting safely. Unless you're Gas Safe registered, it isn't safe to go further than the basic checks above.

Serviceteam's Gas Safe engineers handle Worcester fault 227 day in, day out. If a reset won't clear it, book a boiler repair engineer in London and we'll get your heating back on.

For other Worcester error codes, see our Worcester Bosch fault code guide.

Worcester boiler still showing fault 227 after a reset? Book a Gas Safe boiler repair engineer in London and we’ll get it sorted, day or night.