How much does it cost to fix Ariston error code 50 ❍, red ❍?

Typical repair cost for the Ariston 50 ❍, red ❍ fault is £150-350 including labour.

50 ❍, red ❍ Emergency

Ariston 50 ❍, red ❍ Fault Code

Q: What does the Ariston 50 ❍, red ❍ fault code mean?

Your boiler has detected a flame signal even though it has commanded the gas to turn off, which is a safety concern that requires an immediate check.

Also written as 50RED — same fault.

The Ariston 50 ❍, red ❍ fault code means: your boiler has detected a flame signal even though it has commanded the gas to turn off, which is a safety concern that requires an immediate check.. It appears on 2 Ariston models in our database.

Technical description: Flame detected with gas valve closed

Typical repair cost £150-350 (including labour)

Engineer required

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

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Ariston models that show the 50 ❍, red ❍ fault code

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

Source

Ariston 50 ❍, red ❍ fault code information on this page is sourced and cross-checked against the official Ariston service / installation manuals for each affected model.

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