BoilerFaultCodesYour boiler has detected an issue with how it is getting rid of exhaust fumes, which has caused it to shut down for safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Flue gas/DAPS (Differential Air Pressure Switch) fault
What causes this fault?
This fault occurs when the boiler's safety sensors detect that the fan isn't moving air effectively or that exhaust gases are not being safely cleared through the flue pipe. The most common reason is a blockage in the small plastic tubes inside the boiler, a failing fan motor, or debris obstructing the air passage from outside.
This fault is more common during periods of high winds, which can create back-pressure in the flue that prevents the air pressure switch from closing correctly.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like 03 — no call-out fees, no surprises.
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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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