Medium
353 on Viessmann Vitodens 050-W B0KA-25

Your boiler isn't getting as much gas as it needs, so it's running at reduced power, which usually means it still works but may heat your home and water less effectively until the gas supply is checked.

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

Insufficient gas supply, burner output reduced

From this model's manual
Verified against the Viessmann/Viessmann Vitodens 050 W B0ha B0ka 6194588 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.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

All 131 fault codes on the Vitodens 050-W B0KA-25

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