BoilerFaultCodesYour boiler’s internal computer has encountered a critical error and cannot communicate properly to manage the heating process safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Internal control box error
What causes this fault?
This fault occurs when the boiler's internal computer experiences a hardware failure or a memory corruption loop. The most common reason is that the printed circuit board has worn out over time or has been damaged by a sudden electrical surge, preventing it from processing safety information.
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 E05 — no call-out fees, no surprises.
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Remeha Quinta 115 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.
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