High Lockout
F15 on Ideal Logic Max Combi

Your boiler has stopped working because the internal pump that moves hot water around your pipes has developed an electrical fault or has failed.

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

Pump Fault: Check pump wiring, if OK replace pump

What causes this fault?

This fault occurs when the boiler's main internal unit detects that the pump is no longer spinning or has an electrical connection failure. The most common reason is that the motor inside the pump has burnt out or become seized after years of pushing water through the system. In some cases, it can also be caused by a loose wiring connection or a leak dripping onto the pump's electrical terminals.

This issue is frequently seen at the start of autumn when a pump that has been idle all summer is suddenly asked to work and fails to restart.

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

F2View →L2View →

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