High Lockout
ERROR CODE 8 on Ideal Icos HE

Your boiler has stopped working because the waste water pipe is likely blocked or frozen, causing water to back up into the unit.

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

CONDENSATE BLOCKAGE

What causes this fault?

This fault occurs when the liquid waste produced during the heating process cannot drain away from the boiler. The most common reason is a blockage in the drainage pipe or the internal trap, which causes water to back up into the heat exchanger and trigger a safety shutdown. Often, this happens because debris has built up over time or the pipe has become restricted.

This fault is extremely common during freezing winter temperatures, as the external portion of the condensate pipe can freeze, causing a total blockage.

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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