A63 / A64 / F66 High
Your boiler's main internal computer has developed a technical fault and can no longer control the heating system safely.
Technical description: Controller ABM03B error – controller internal error
Typical repair cost: £250-£450 (including labour)
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Protect yourself from future repair bills
A boiler cover plan would cover faults like A63 / A64 / F66 — no call-out fees, no surprises.
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Parts commonly replaced
- Main PCB (ABM03B Control Board)
- Wiring Harness
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