What does the Grant RED blinking (0.5s) fault code mean?

Your boiler has detected a signal that it is already burning fuel even though it has not been told to start, so it has safely shut itself down to prevent an unsafe situation.

How much does it cost to fix Grant error code RED blinking (0.5s)?

Typical repair cost for the Grant RED blinking (0.5s) fault is £150-300 including labour.

Grant RED blinking (0.5s) Fault Code: What It Means & How to Fix It

Technical description

Lockout for false flame signal

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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Your boiler has detected a signal that it is already burning fuel even though it has not been told to start, so it has safely shut itself down to prevent an unsafe situation.

Technical description

Engineer required

Related guides you might find useful

Yellow or orange flame — CO safety

When to replace your boiler

Is boiler cover worth it?

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