High Lockout
ERROR CODE 7 on Ideal Icos HE

Your boiler has shut down because it has detected that the exhaust gases are becoming dangerously hot, which usually suggests a serious internal blockage or a lack of water circulation.

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

FLUE OVERHEAT

What causes this fault?

This fault occurs when the internal sensors detect that the exhaust gases are reaching unsafe temperatures, triggering an emergency shutdown to protect the appliance. The most common reason is a lack of water flowing through the heat exchanger to carry the heat away, often caused by a failed pump or a significant internal blockage. In some cases, it can also be triggered by a heavy buildup of limescale or debris within the main heat exchanger itself.

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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