High Lockout
F13 on Ideal Logic Max Combi

Your boiler has stopped working because the internal pump that moves water around your heating system has failed or cannot communicate with the control board.

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 control board detects that the internal pump is either completely unresponsive or failing to reach the required speed to move water. The most common reasons are electrical failure within the pump motor itself or the pump becoming physically seized after long periods of inactivity.

This fault is particularly common in autumn when the heating is turned back on for the first time, as the pump can seize up after sitting idle throughout the summer.

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

F1View →F4View →L1View →

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