High Lockout
E83489 on Potterton Powermax HE

Your boiler has detected a leak or a failure in the internal seals that keep the water system watertight, which will likely prevent the unit from operating 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.

Technical description

‘O’Rings/Seals Kit - Water Components

What causes this fault?

This fault occurs when the boiler detects an internal water leak or a significant drop in pressure caused by failing rubber seals within the pipework connections. Over years of constant heating and cooling, these internal O-rings can perish or become brittle, eventually allowing water to seep into areas where it shouldn't be. The boiler's sensors identify this loss of integrity or the presence of moisture and shut the system down to prevent electrical damage or flooding.

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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Related fault codes

A01View →E01View →

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