BoilerFaultCodesWhat the manual says
Manufacturer manualWhen the burner starts, no temperature increase is registered at the flow or return temperature sensor or the temperature increase here is too slow.
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.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.017S.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