BoilerFaultCodes.com
304 Low Lockout

Your boiler has gone into a temporary lockout because it has been reset too many times in a short period.

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description: All Boilers

What causes this fault?

This fault occurs when the 'Reset' button has been pressed more than five times within a fifteen-minute window. It is a safety feature designed to prevent you from repeatedly clearing an underlying fault without actually fixing the source of the problem. Following this lockout, the boiler will remain disabled for several minutes before it allows you to try again.

Typical repair cost £0 (including labour)

DIY fix possible

Switch the boiler off at the main electrical fused spur switch or wall socket.Wait for approximately 30 seconds.Switch the power back on and wait for the boiler to complete its start-up sequence.

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