What does the Alpha 20 fault code mean?

Your boiler is struggling to detect the flame needed to heat your water, even if the burner has successfully lit.

How much does it cost to fix Alpha error code 20?

Typical repair cost for the Alpha 20 fault is £90-250 including labour.

Alpha 20 Fault Code: What It Means & How to Fix It

Technical description

Flame sensing fault

What causes this fault?

This fault occurs when the boiler's control system cannot confirm that a flame is present, even if the burner is actually firing. The most common reason is a buildup of carbon or debris on the monitoring probe, or a loose electrical connection that prevents the signal from reaching the main control board.

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 is struggling to detect the flame needed to heat your water, even if the burner has successfully lit.

Technical description

What causes this fault?

Engineer required

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