Low
d.08 on Vaillant Turbomax Plus VUW 242EH

Your boiler is currently receiving a signal from your thermostat or timer telling it that no heating or hot water is required at this moment.

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

External controls heat demand 0 = open, no demand; 1 = closed, demand

From this model's manual
Verified against the Vaillant/Vaillant Turbomax Plus 824 828e installation & service manual, page 39.
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 your room thermostat or smart controller settings to ensure they are calling for heat.Verify that your timer or programmer is set to the 'On' position.Ensure the batteries in your wireless room thermostat are not flat.

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Related fault codes

d.09View →

All 92 fault codes on the Turbomax Plus VUW 242EH

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

d.00d.01d.02d.05d.07d.10d.11d.21D.22d.23D.24d.25d.30d.33d.34d.35d.37d.40d.41d.50d.60d.61d.64d.65d.67d.68d.69d.71d.72d.73d.75d.76d.80d.81d.82d.83F 22F.00F.01F.10F.11F.20F.22F.23F.24F.27F.28F.29F.32F.33F.37F.41F.42F.43F.60F.61F.62F.63F.64F.65F.66F.67S.00S.01S.02S.03S.04S.05S.07S.08S.10S.11S.13S.14S.16S.17S.20S.21S.23S.24S.27S.28S.30S.31S.32S.33S.34S.36S.39S.53S.54

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