Medium
D.070 on Vaillant ecoTEC plus 624

Your boiler is struggling to switch between heating your radiators and heating your hot water because an internal diverter component is failing to move correctly.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

3-way valve operation

From this model's manual
Verified against the Vaillant/Vaillant Ecotec Plus 624 4104463 installation & service manual, page 57.
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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Related fault codes

F.70View →F.71View →

All 121 fault codes on the ecoTEC plus 624

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.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.76F.77F.78F.83F.84F.85F.91F.92F.93S.11S.16S.17S.24

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