BoilerFaultCodesYour boiler's electronic control centre has developed an internal fault and is unable to communicate with the rest of the system.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Printed circuit board (PCB) fault
What causes this fault?
This fault occurs when the boiler's internal computer brain suffers a hardware failure or a breakdown in its electronic circuitry. The most common reason is age-related wear to the electrical components on the board, though it can also be triggered by a sudden power surge or moisture getting into the control box.
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 E3 — no call-out fees, no surprises.
Affiliate links — we may earn a commission at no extra cost to you.
Baxi Avanta 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.