BoilerFaultCodesYour boiler has detected that the fan, which safely clears waste gases away, is not spinning as fast as it needs to for the boiler to light safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Fan not running at maximum speed.
What causes this fault?
This fault occurs when the boiler's internal computer detects that the fan is not reaching the necessary speed to safely expel exhaust gases. The most common reasons are a build-up of dirt within the fan or a blockage in the small tubes that monitor air pressure. If the fan cannot create enough airflow, the boiler will prevent ignition to ensure carbon monoxide doesn't build up inside the unit.
This fault can be more frequent during autumn or windy weather, as debris or strong gusts can obstruct the flue or put extra strain on a struggling fan motor.
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.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like 50° neon flashing — no call-out fees, no surprises.
Affiliate links — we may earn a commission at no extra cost to you.
Potterton Performa 28i 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.
Affiliate links — we may earn a commission at no extra cost to you.