BoilerFaultCodesWhat the manual says
Manufacturer manualThe domestic hot water draw-off is active and the heating pump is in overrun mode.
From this model's manual
Verified against the Vaillant/Vaillant Vaillantpro 0020308121 05 Ecotecplus Storage Combi Installation installation & service manual.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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All 166 fault codes on the ecoTEC plus 940
Seeing a different code? Every code this model can display, in one place.
F.000F.001F.002F.003F.010F.011F.012F.013F.020F.022F.023F.024F.025F.027F.028F.029F.032F.035F.040F.042F.044F.047F.049F.057F.061F.062F.063F.064F.065F.067F.068F.070F.071F.072F.074F.075F.076F.077F.078F.080F.081F.083F.084F.085F.087F.088F.089F.090F.092F.095F.096F.097F.105F.194F.195F.196F.317F.318F.320F.321F.322F.323F.324F.325F.326F.327F.330F.334F.336F.337F.338F.342F.343F.344F.347F.363F.707F.905I.003I.020I.144L.016L.022L.025L.032L.095L.096L.097L.105L.144L.194L.195L.196L.319L.320L.322L.343N.013N.027N.032N.089N.095N.096N.097N.100N.144N.194N.270N.317N.319N.324N.343S.000S.001S.002S.003S.004S.005S.006S.007S.008S.009S.010S.011S.012S.013S.014S.015S.016S.019S.020S.021S.022S.023S.024S.025S.026S.027S.028S.029S.030S.031S.032S.034S.039S.041S.042S.054S.057S.059S.088S.091S.092S.093S.096S.097S.098S.109S.175S.199S.326S.328S.335S.341S.599