BoilerFaultCodesWhat the manual says
Manufacturer manualFault: Flow/return temperature sensor temperature difference implausible Flow and return temperature sensors returning implausible values. - Flow and return temperature sensors have been inverted. - Flow and return temperature sensors have not been correctly fitted.
Shared across the ecoTEC plus range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Related fault codes
All 77 fault codes on the ecoTEC plus
Seeing a different code? Every code this model can display, in one place.
Communication faultD.17F.00F.01F.02F.03F.10F.11F.12F.13F.20F.22F.23F.24F.25F.26F.27F.28F.29F.32F.35F.42F.49F.52F.53F.54F.56F.57F.61F.62F.63F.64F.65F.67F.68F.70F.71F.72F.73F.74F.75F.76F.77F.78F.83F.85F.91F.92F.93S.10S.11S.13S.14S.15S.16S.17S.20S.21S.22S.23S.24S.25S.26S.27S.28S.30S.31S.32S.34S.41S.42S.53S.54S.96S.97S.98