High Lockout
F7 on Ideal Logic Max Combi

Your boiler has stopped working because the electrical power coming into your home is at a lower voltage than it needs to operate 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

LOW MAINS VOLTAGE - CONTACT ELECTRICITY PROVIDER

What causes this fault?

This fault occurs when the electrical supply entering the boiler drops below 190 volts, which is too low for the internal components to function. While it is sometimes caused by a failing control board within the boiler, it most commonly originates from an issue with the National Grid supply or the electrical wiring leading to your home.

This fault is occasionally more frequent during winter or periods of extreme weather when the local electrical grid is under high demand or power lines are affected by storms.

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

L2View →F2View →

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