Medium
815 W on Worcester Bosch Greenstar 8000+ GR8701iW 30 R

Your boiler is receiving incorrect temperature readings because a sensor attached to a specialist heating component is failing, which may temporarily stop your heating system from working properly.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

Low loss header temp. sensor faulty

From this model's manual
Verified against the Worcester Bosch/Worcester Bosch Wb 47116 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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Related fault codes

815View →EAView →D7View →

All 87 fault codes on the Greenstar 8000+ GR8701iW 30 R

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

228 V229 B232 B233 V234 V235 V237 V238 V242244245246247248249250251252253254257 V258259262 V265 B268 O269 V273 B281 B283 O284 O306 V357 O358 O360 V362 V363 V6041010 O1013101810191022102310251037 W1068 W1070107110721075 W1076 W2085 V2908 V2910 V2914291529162920 V2923 V2924292529262927292829312940 V2946 V2948 B2949 B2950 B2951 V2952 V2955 B2956 O2957 V2961 V29622963 B2965 B2966 B2968 O296929722980 V2981 V

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