Low
353 on Worcester Bosch Greenstar 2000 GR2300iW 25 C

Your boiler is undergoing a factory test mode or internal diagnostic check and has temporarily paused its normal operation.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

Test non-v

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 fault requires 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 V2502512522532542562572582592622632642652682692702732752812832843053063233283413423503513543563573583603623633643656048101010101310141018101910211023102510371068107310741075107620512085290829092910291129122913291429152916291729182920292129222923292429252926292729282930293129322940294129422943294529462947294829492950295129522953295429552956295729582959296029612962296329642965296629672972297329743071

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