High
258 on Worcester Bosch Greenstar 2000 GR2300iW 25 C

Your boiler's internal computer is experiencing a temporary software glitch and has shut down to prevent any unsafe operation.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

What the manual says

Manufacturer manual

Internal watchdog error

From this model's manual
Verified against the Worcester Bosch/Worcester Bosch Wb 45175 installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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All 129 fault codes on the Greenstar 2000 GR2300iW 25 C

Seeing a different code? Every code this model can display, in one place.

215 V224 B/V227 B/V228 V229 B232 B233 V234 V235 V237 V238 V242 V244 V245 V246247249249 V2502512522532542562572592622632642652682692702732752812832843053063233283413423503513533543563573583603623633643656048101010101310141018101910211023102510371068107310741075107620512085290829092910291129122913291429152916291729182920292129222923292429252926292729282930293129322940294129422943294529462947294829492950295129522953295429552956295729582959296029612962296329642965296629672972297329743071

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