How much does it cost to fix Atag error code 501?

Typical repair cost for the Atag 501 fault is £100-350 including labour.

501 High

Atag 501 Fault Code

Q: What does the Atag 501 fault code mean?

Your boiler is failing to light the gas, which means it cannot provide the heating or hot water you need.

The Atag 501 fault code means: your boiler is failing to light the gas, which means it cannot provide the heating or hot water you need.. It appears on 18 Atag models in our database.

Technical description: No flame detected

Typical repair cost £100-350 (including labour)

DIY fix possible

Check that your gas supply is turned on and other gas appliances are working.If you have a prepay meter, ensure you have sufficient credit.Press the Reset button once to see if the boiler restarts.

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Atag models that show the 501 fault code

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

Source

Atag 501 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 31 August 2026