What does the Viessmann 299 fault code mean?

The boiler's internal clock has lost or confused its time and date, which usually affects timed heating schedules rather than the heating or hot water themselves.

How much does it cost to fix Viessmann error code 299?

Typical repair cost for the Viessmann 299 fault is £90-250 including labour.

Viessmann 299 Fault Code: What It Means & How to Fix It

What the manual says

Manufacturer manual

Real-time clock fault

From this model's manual

Verified against the Viessmann/Viessmann Vitodens 100 W B1hf B1kf 6167586 installation & service manual.

DIY fix possible

Press the reset button on the boiler control panel or switch the boiler off at its power supply for a minute, then switch it back on.Use the control dial and menu on the boiler to check and set the correct time and date.Check that your heating and hot water timer settings are still correct, then watch to see if the code clears. If it returns, call a Gas Safe registered engineer.

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Related fault codes

F.28View →F.22View →

All 151 fault codes on the Vitodens 100-W B1HF-19

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

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The boiler's internal clock has lost or confused its time and date, which usually affects timed heating schedules rather than the heating or hot water themselves.

What the manual says

DIY fix possible

Avoid the next call-out bill

Related fault codes

All 151 fault codes on the Vitodens 100-W B1HF-19

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