High Lockout
Green zone; end of green zone on Remeha Gas 610 Eco Pro

Your boiler is struggling to light or keep its main flame burning steadily, which is preventing it from heating properly.

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

failing or unstable flame of main burner

What causes this fault?

This fault occurs when the boiler's control system cannot detect a steady flame after trying to ignite the gas. The most common reasons are a worn-out sensing probe that can no longer see the flame, or a faulty gas valve that isn't providing the correct amount of fuel to keep the burner lit safely.

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
Search the official register →

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