How much does it cost to fix Ariston error code EE 9955?

Typical repair cost for the Ariston EE 9955 fault is £120-200 including labour.

EE 9955 High

Ariston EE 9955 Fault Code

Q: What does the Ariston EE 9955 fault code mean?

Your boiler is struggling to accurately measure how hot the water is inside the system, so it has safely shut down to prevent overheating.

Also written as EE9955 — same fault.

The Ariston EE 9955 fault code means: your boiler is struggling to accurately measure how hot the water is inside the system, so it has safely shut down to prevent overheating.. It appears on 4 Ariston models in our database.

Technical description: Error reading flow or return temperature probe

Typical repair cost £120-200 (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 EE 9955 fault code

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

Source

Ariston EE 9955 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