How much does it cost to fix Alpha error code 0A30?

Typical repair cost for the Alpha 0A30 fault is £120-220 including labour.

0A30 High

Alpha 0A30 Fault Code

Q: What does the Alpha 0A30 fault code mean?

Your boiler is struggling to detect the flow of water because of a faulty electrical connection inside the unit, meaning it will likely refuse to heat your water.

The Alpha 0A30 fault code means: your boiler is struggling to detect the flow of water because of a faulty electrical connection inside the unit, meaning it will likely refuse to heat your water.. It appears on 3 Alpha models in our database.

Technical description: Flow sensor short circuit.

What causes the Alpha 0A30 fault?

This fault occurs when the electrical component responsible for monitoring the temperature of the water leaving your boiler develops a short circuit. The most common reason is that the sensor's internal casing has failed or moisture has entered the electrical connector, causing the boiler to shut down for safety because it can no longer track how hot the water is becoming.

Typical repair cost £120-220 (including labour)

Engineer required

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

Find a Gas Safe engineer

Search the official register for a qualified engineer in your area.

Gas Safe Register →

Alpha models that show the 0A30 fault code

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

Source

Alpha 0A30 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