High
PCB Fault on Ideal Logic Max Heat

Your boiler's internal computer has suffered a critical failure and can no longer control the heating system safely.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

What the manual says

Manufacturer manual

Contact Installer

From this model's manual
Verified against the Ideal Logic Max Heat installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

What causes this fault?

This fault occurs when the boiler's main control board suffers an electrical failure, preventing it from processing instructions or monitoring safety sensors. The most common reasons are internal component wear, moisture ingress, or an electrical surge that has damaged the delicate circuitry on the board.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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