Low
815 on Worcester Bosch 2000 GC2000iW 25 C NG

Your boiler is struggling to read the temperature accurately from an optional heating component called a low loss header, which may temporarily affect how efficiently your system distributes warmth.

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

Faulty low loss header temperature sensor.

From this model's manual
Verified against the Worcester Bosch/Worcester Bosch 2000 Gc2000iw 2019 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

816View →817View →A1View →

All 144 fault codes on the 2000 GC2000iW 25 C NG

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

20020120220320420720821221421522422722822923223323423523723824224424524624724925025125225325425625725825926226326426526826927027327528130530632332834134235035135635735836036236336436560481010131014101710181021102210231065106810731074107510762051208529082909291029112912291329142915291629172918292029212922292329242925292629272928293029312932294029412942294329452946294729482949295029512952295329542955295629572958295929602961296229632964296529662967296829692971297229732974b1C1C4C6Constant redd1d3E2Flashing red

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