Unknown
F.76 on Vaillant ecoTEC plus 612

Vaillant ecoTEC plus 612 fault code F.76

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

What the manual says

Manufacturer manual

Overheating protection on primary heat exchanger has responded Cable or cable connections for safety fuse in primary heat exchanger or primary heat exchanger defective

From this model's manual
Verified against the Vaillant/Vaillant Ecotec Plus 612 4104460 installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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All 121 fault codes on the ecoTEC plus 612

Seeing a different code? Every code this model can display, in one place.

Communication faultD.000D.001D.002D.003D.004D.005D.006D.007D.008D.009D.010D.011D.012D.013D.014D.015D.016D.017D.018D.019D.020D.022D.023D.025D.026D.027D.028D.033D.034D.035D.036D.039D.040D.041D.044D.046D.047D.050D.051D.058D.060D.061D.064D.065D.067D.068D.069D.070D.071D.072D.073D.075D.076D.077D.078D.080D.081D.082D.083D.084D.088D.090D.091D.093D.094D.095D.096D.098F.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.77F.78F.83F.84F.85F.91F.92F.93S.11S.16S.17S.24

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