BoilerFaultCodesWhat the manual says
Manufacturer manualIncorrect earth connection between cable harness and product, flow or return NTC defective (loose connection), stray spark via ignition cable, ignition plug or ignition electrode Only in liquefied petroleum gas operation or in cascade mode: The differential pressure sensor was not replaced with a bypass valve; the bypass valve is not functional
From this model's manual
Verified against the Vaillant/Vaillant Ecotec Exclusive 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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Related fault codes
All 207 fault codes on the ecoTEC exclusive 835 VUW 356/5-7
Seeing a different code? Every code this model can display, in one place.
conF.00F.00F.01F.01F.02F.02F.03F.03F.10F.10F.11F.11F.12F.12F.13F.13F.22F.22F.23F.23F.24F.24F.25F.25F.26F.26F.27F.27F.28F.28F.29F.29F.32F.32F.33F.33F.35F.35F.42F.42F.49F.49F.55F.55F.56F.56F.57F.57F.61F.61F.62F.62F.63F.63F.64F.64F.65F.65F.67F.67F.68F.68F.70F.70F.71F.71F.72F.72F.73F.73F.74F.74F.75F.75F.77F.77F.78F.78F.80F.80F.81F.81F.82F.82F.83F.83F.84F.84F.85F.85F.90F.90F.94F.94P.00P.01P.02P.04P.06P.14S.00S.01S.2S.02S.3S.03S.04S.05S.06S.07S.08S.09S.09S.10S.10S.11S.11S.13S.13S.14S.14S.15S.15S.16S.16S.17S.17S.19S.19S.20S.20S.21S.21S.22S.22S.23S.23S.24S.24S.25S.25S.26S.26S.27S.27S.28S.28S.29S.29S.30S.30S.31S.31S.32S.32S.33S.33S.34S.34S.36S.36S.37S.37S.39S.39S.40S.40S.41S.41S.42S.42S.46S.46S.53S.53S.54S.54S.55S.55S.56S.56S.57S.57S.58S.58S.59S.59S.76S.76S.86S.86S.88S.88S.92S.92S.93S.93S.96S.96S.97S.97S.98S.98S.99S.99