BoilerFaultCodesYour boiler's main internal computer has lost touch with the display panel, meaning the controls cannot talk to the heating unit.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Communication fault between PCB and programming unit (user interface)
What causes this fault?
This fault occurs when the data link between the boiler's main brain and the control screen is broken or interrupted. The most common reason is a loose internal connection or a failure of the delicate wiring that carries signals between the two components.
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 A8 — no call-out fees, no surprises.
Affiliate links — we may earn a commission at no extra cost to you.
Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
Affiliate links — we may earn a commission at no extra cost to you.