Medium
P.6 on Vaillant ecoTEC plus 612 VU GB 126/3-5

Your boiler has temporarily stopped because it detected a sudden and unusual rise in internal temperature.

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

not available

From this model's manual
Verified against the Vaillant/Vaillant Ecotec Plus Pro 839592 00 2004 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 that your home's radiators are turned on and the valves are not completely closed.Verify that the system water pressure is at the correct level, usually between 1 and 1.5 bar.Reset the boiler using the reset button to see if normal operation resumes.

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Related fault codes

F.20View →F.22View →P.0View →

All 119 fault codes on the ecoTEC plus 612 VU GB 126/3-5

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

d.00d.01d.02d.03d.05d.06d.07d.08d.09d.10d.11d.17d.18d.19d.22d.23d.25d.26d.30d.33d.34d.35d.36d.40d.41d.44d.47d.50d.51d.60d.61d.64d.65d.67d.68d.69d.70d.71d.72d.73d.75d.76d.77d.78d.80d.81d.82d.83d.84d.90d.91d.93d.97F.00F.01F.02F.10F.11F.13F.20F.22F.23F.24F.27F.28F.29F.32F.60F.61F.62F.63F.64F.65F.70F.71F.72F.73F.74F.75F.76P.1P.2P.3P.4P.5S.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.36S.53S.54S.76

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