BoilerFaultCodesWhat the manual says
Manufacturer manualExternal controls heat demand
From this model's manual
Verified against the Vaillant/Vaillant Ecotec Plus Aquaplus installation & service manual.
DIY fix possible
Check your room thermostat to see if it is turned up higher than the current room temperature.Verify if your central heating timer or programmer is currently set to an 'on' period.No action is required if you actually want the heating to be running, as this is a status message rather than a fault.
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Related fault codes
All 106 fault codes on the ecoTEC plus aquaPLUS
Seeing a different code? Every code this model can display, in one place.
d.00d.01d.02d.03d.04d.05d.06d.10d.11d.12d.13d.21d.22d.23d.24d.25d.30d.33d.34d.35d.37d.40d.41d.50d.60d.61d.64d.65d.67d.68d.69d.71d.72d.76d.79d.80d.81d.82d.83F.00F.01F.02F.03F.10F.11F.12F.13F.20F.22F.23F.24F.27F.28F.29F.32F.33F.37F.41F.42F.43F.60F.61F.62F.63F.64F.65F.66F.67P.11P.12P.13S.00S.01S.02S.03S.4S.04S.05S.06S.07S.08S.10S.11S.13S.14S.15S.16S.17S.20S.21S.23S.24S.25S.26S.27S.28S.30S.31S.32S.33S.34S.36S.39S.53S.54