High Lockout
ERROR CODE 2 on Ideal Icos HE

Your boiler has become too hot and has shut itself down as a safety precaution to prevent damage.

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.

Technical description

OVERHEAT ALARM

What causes this fault?

This fault occurs when the internal water temperature reaches an unsafe level, causing the boiler to shut down to protect its internal components. The most common reasons are a failed pump that isn't circulating the water, a blockage in the system, or a buildup of air that prevents heat from being carried away from the heat exchanger.

This issue is more common during the first cold spell of autumn when the heating is turned back on after sitting idle all summer, which can cause the pump to seize.

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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