BoilerFaultCodesWind or air is blowing back down your boiler's chimney, which is preventing the exhaust fumes from escaping safely.
Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now — this fault can be dangerous if ignored.
Technical description: Downdraught
What causes this fault?
This fault occurs when strong gusts of wind enter the flue pipe and push air back into the boiler, disrupting the internal pressure balance. The most common reason is that the flue terminal is positioned in an area exposed to high winds or is missing a protective guard, causing the safety sensors to trigger a shutdown to prevent fumes from entering the home.
This fault is much more frequent during autumn and winter months when high winds and stormy weather conditions are prevalent.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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A boiler cover plan would cover faults like 72 — no call-out fees, no surprises.
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Worcester Bosch Greenstar Utility 18/25 is discontinued — time for a new one?
Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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