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BoilerCodes
224Worcester Bosch

Worcester Bosch 224: what it means on your model

Checked against Worcester Bosch's own documentation: Worcester Greenstar 4000 installation and maintenance instructions: fault code table and 1 more source. Last reviewed October 2026. How we check

Engineer only

224 means different things on different Worcester Bosch models. Check the table below against your boiler's model name, which is usually on the front panel or in your user manual.

What you can safely do

There is nothing you can safely do yourself with this one. Leave the boiler off and book an engineer.

Before you book an engineer

  • Write down the code exactly as the display shows it: 224.
  • Find your boiler's model name. It is usually on the front panel or in the user manual. The table below shows why it matters: Worcester Bosch codes can mean different things on different models.
  • Note when it started and what the boiler was doing (heating, hot water, or starting up).
  • If the boiler is still under warranty, check your warranty paperwork before you book anyone.

Call a Gas Safe engineer if

  • Book a Gas Safe registered engineer.
Find a Gas Safe engineer near you Opens the official Gas Safe Register search.

Applies to Greenstar 4000, Greenstar 8000 Life. Codes can differ between models, so check your manual.

What 224 means on each Worcester Bosch model

From Worcester Bosch's own fault tables. Your model name is usually on the front of the boiler or in the user manual.

ModelMeaning
Greenstar 4000Maximum flue gas thermostat or heat exchanger maximum thermostat has activated
Greenstar 8000 LifeSafety temperature limiter has tripped

Common questions about Worcester Bosch 224

Can I fix Worcester Bosch 224 myself?

No. It needs a Gas Safe registered engineer to diagnose. Tell them the exact code and your boiler's model name.

Nearby Worcester Bosch codes

See all 28 Worcester Bosch codes

Sources

Last reviewed October 2026. Spotted something that doesn't match your manual? Email hello@boilercodes.co.uk and we'll check it. How we check