What does the Grant Off fault code mean?

Your boiler's burner has detected light when it should be dark inside, causing it to shut down for safety.

How much does it cost to fix Grant error code Off?

Typical repair cost for the Grant Off fault is £90-180 including labour.

Can I fix Grant fault code Off myself?

Check that the burner cover and all casing panels are securely fitted and not letting in external light.

Grant Off Fault Code: What It Means & How to Fix It

Technical description

Eliminate the extraneous light

What causes this fault?

This fault occurs when the boiler's internal light sensor detects a flame or light source before the ignition process has even started. The most common reasons are a faulty sensor sending a false signal, a leaking fuel valve allowing a stray flame to persist, or light leaking into the burner housing through damaged seals.

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.

Find a Gas Safe engineer

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Your boiler's burner has detected light when it should be dark inside, causing it to shut down for safety.

Technical description

What causes this fault?

Engineer required

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