BoilerFaultCodesWhat the manual says
Manufacturer manualError with gas valve – possible no function
From this model's manual
Verified against the Vaillant/Vaillant Ecotec Pro Ecotec Plus Regular installation & service manual.
What causes this fault?
This fault occurs when the boiler's main computer loses electrical communication with the gas valve, which acts as the 'tap' for the fuel. The most common reason is an internal electrical failure within the valve's motor or a loose connection in the wiring that prevents the valve from opening or closing as instructed.
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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Related fault codes
All 101 fault codes on the ecoTEC Pro / ecoTEC Plus
Seeing a different code? Every code this model can display, in one place.
F.00F.01F.02F.03F.10F.11F.12F.13F.20F.22F.23F.24F.25F.27F.28F.29F.32F.42F.49F.52F.53F.54F.55F.56F.57F.61F.62F.63F.64F.65F.67F.68F.70F.71F.72F.73F.74F.75F.77F.78F.80F.81F.82F.83F.84F.85F.90F.91F.92F.93F.94S.00S.01S.02S.03S.04S.05S.06S.07S.08S.10S.11S.13S.14S.15S.16S.17S.20S.21S.22S.23S.24S.25S.26S.27S.28S.30S.31S.32S.34S.39S.40S.41S.42S.46S.53S.54S.57S.58S.61S.62S.63S.76S.88S.92S.93S.96S.97S.98S.99