Your boiler's control panel has developed a communication fault and is unable to send or receive correctly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Faulty programming unit (user interface)
What causes this fault?
This fault occurs when the main brain of the boiler loses touch with the display panel where you adjust your settings. The most common reason is a physical hardware failure within the control unit itself or a loose internal wiring connection that prevents data from flowing back and forth. Because the display can no longer tell the boiler what to do, the system shuts down for safety.
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 A7 — 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.