Low
S.40 on Vaillant ecoTEC plus 832 VUW 246/5-5 R6

Your boiler is temporarily running at a lower power level to prevent a fault and ensure it can still provide some warmth while it detects a minor issue.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

Comfort protection active: The comfort protection mode is activated.

From this model's manual
Verified against the Vaillant/Vaillant Ecotec Pro Ecotec Plus Regular 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.

DIY fix possible

Check for any other error codes on the displayMonitor the boiler to see if it returns to normal operation automaticallyEnsure all radiator valves are open to allow for maximum heat dissipationIf the message persists, book a routine service with a Gas Safe engineer to check sensor readings

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Related fault codes

F.20View →F.22View →F.24View →

All 175 fault codes on the ecoTEC plus 832 VUW 246/5-5 R6

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

D.000D.001D.002D.003D.004D.005D.006D.008D.009D.010D.011D.012D.013D.015D.016D.017D.018D.020D.022D.023D.025D.026D.027D.028D.029D.033D.034D.035D.036D.039D.040D.041D.047D.058D.060D.061D.064D.065D.067D.068D.069D.070D.071D.072D.073D.074D.075D.077D.078D.080D.081D.082D.083D.084D.088D.090D.091D.092D.093D.094D.095D.096D.098F.00F.01F.02F.03F.10F.11F.12F.13F.20F.22F.23F.24F.25F.26F.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.94P.00P.0P.01P.02P.06S.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.41S.42S.46S.53S.54S.57S.58S.61S.62S.63S.76S.88S.92S.93S.96S.97S.98S.99T.02T.03T.04T.05T.06T.08

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