How much does it cost to fix Alpha error code 0A7?

Typical repair cost for the Alpha 0A7 fault is £150-300 including labour.

0A7 High

Alpha 0A7 Fault Code

Q: What does the Alpha 0A7 fault code mean?

Your boiler has detected that the exhaust gases are becoming dangerously hot, so it has safely shut itself down to prevent damage.

The Alpha 0A7 fault code means: your boiler has detected that the exhaust gases are becoming dangerously hot, so it has safely shut itself down to prevent damage.. It appears on 3 Alpha models in our database.

Technical description: High flue temperature fault. Check for air in t

What causes the Alpha 0A7 fault?

This fault occurs when the internal heat exchanger isn't transferring heat efficiently to the water, causing the leftover heat to escape into the exhaust flue at dangerous levels. The most common reasons are a buildup of debris and sludge inside the main heat exchanger or a failing sensor that is incorrectly reading the exhaust temperature.

Typical repair cost £150-300 (including labour)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Alpha models that show the 0A7 fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Alpha 0A7 fault code information on this page is sourced and cross-checked against the official Alpha service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026