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Worcester Bosch Greenstar 2000 Fault Codes

The Worcester Bosch Greenstar 2000 is the brand's entry-level combi — a compact, keenly priced boiler launched in 2021 to compete at the affordable end of the market without giving up the Worcester name. Underneath, it runs the same modern Bosch control architecture as its bigger siblings, so it speaks the same fault-code language: a primary code such as EA or C6, generally with a numeric sub-code that sharpens the diagnosis. Because the 2000 is aimed at smaller homes and tighter budgets, its owners are often first-time boiler owners too — so it is worth saying plainly: a fault code is the boiler explaining itself, not just complaining. Most codes on this page have a specific meaning, several have five-minute homeowner fixes (pressure top-ups above all), and the rest tell a Gas Safe engineer exactly where to start. Each code below links through to its full explanation.

Where Greenstar 2000 fault codes appear

The 2000 keeps things minimal: a small display on the front shows temperature in normal operation and the fault code when locked out, typically with sub-code. There is no scrolling text as on the 8000 Life — just the code — so noting it exactly (letters, numbers, spacing) matters all the more before you reset.

Resetting a Worcester Bosch Greenstar 2000

Press and hold the reset button until the display responds, then release; the boiler retries. Low-pressure lockouts need the system topped up to 1–1.5 bar via the filling loop before resetting. If a code returns straight away, or the same code recurs across days, book a Gas Safe engineer rather than making resetting a routine.

Common Greenstar 2000 problems

On the 2000 the recurring themes are the platform's usual suspects: ignition lockouts in the EA family (frozen condensate pipes being the seasonal classic), pressure loss on the sealed system, and occasional fan/flue C-codes. As a compact boiler often installed in smaller spaces, the 2000 also sees its share of flue and condensate runs with tight routing — worth an engineer's look if flue-related codes recur.

Most common Greenstar 2000 fault codes

Last reviewed 25 August 2026.

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