BoilerFaultCodesYour boiler is failing a self-test of its internal fan, which is preventing the system from starting up 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 test – checking the basic fan
What causes this fault?
This fault occurs when the boiler's control system tries to start the fan but doesn't receive the correct feedback signal telling it the motor is spinning. The most common reason is that the fan motor has physically worn out or its internal electronics have failed, though it can also be caused by loose wiring connections or a fault on the main control board.
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 T2 — no call-out fees, no surprises.
Affiliate links — we may earn a commission at no extra cost to you.
Worcester Bosch Greenstar Si Combi / i System 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.