How much does it cost to fix Atag error code 151?

Typical repair cost for the Atag 151 fault is £200-350 including labour.

151 High

Atag 151 Fault Code

Q: What does the Atag 151 fault code mean?

Your boiler's internal fan, which is responsible for safely venting fumes, is failing to spin at the correct speed, causing the system to stop working for safety reasons.

The Atag 151 fault code means: your boiler's internal fan, which is responsible for safely venting fumes, is failing to spin at the correct speed, causing the system to stop working for safety reasons.. It appears on 4 Atag models in our database.

Technical description: Fan error (speed control is not achieved or is out of range) or control unit defective

Typical repair cost £200-350 (including labour)

Engineer required

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

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Atag models that show the 151 fault code

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

Source

Atag 151 fault code information on this page is sourced and cross-checked against the official Atag service / installation manuals for each affected model.

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