Your boiler has stopped working because it cannot safely vent exhaust gases or draw in fresh air due to a blockage in the pipes.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Blocked flue/air intake (high resistance)
What causes this fault?
This fault occurs when the boiler's internal safety sensors detect that the fan is unable to push exhaust gases out of the flue or pull in enough oxygen for combustion. The most common reasons include a physical obstruction in the external pipework, such as a bird's nest or debris, or a mechanical failure of the fan itself which prevents it from reaching the necessary speed.
This fault is slightly more common during autumn and winter, as fallen leaves or nesting birds can cause blockages in the flue outlet.
DIY fix possible
Check the external flue pipe outside your home for any obstructions like bird nests, leaves, or debrisEnsure there is no snow or ice buildup covering the flue outletCarefully remove any external blockages you can see from the outside
Find a Gas Safe engineer
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Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like E39 — no call-out fees, no surprises.
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Remeha Quinta 115 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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