BoilerFaultCodesWhat the manual says
Manufacturer manualThe coding resistor (in the wiring harness) or the gas group resistor (on the PCB, if available) is invalid.
From this model's manual
Verified against the Vaillant/Vaillant Vaillantpro 0020308121 05 Ecotecplus Storage Combi Installation installation & service manual.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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All 125 fault codes on the ecoTEC plus 940 VUI 30/40CS/1-5
Seeing a different code? Every code this model can display, in one place.
194F.000F.001F.002F.003F.010F.011F.012F.013F.020F.022F.023F.024F.025F.027F.028F.029F.032F.035F.040F.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.343P.000P.001P.003P.008P.021T.001T.002T.003T.004T.005T.006T.007