Overheating High

Ariston Overheating Fault Code

Also written as OVERHEATING — same fault.

The Ariston Overheating fault code means: your boiler has shut down because it has detected that the water inside the system has become dangerously hot.. It appears on 1 Ariston model in our database.

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description: Control shuts off the boiler if the primary circuit reaches a temperature in excess of 105°C. Red L.E.D. 'H' will illuminate.
Typical repair cost £120-350 (including labour)

DIY fix possible

Locate the reset button (usually marked 'R') on the control panel and press it.Ensure all radiator valves are fully open to allow water to flow freely.Check that your system pressure is between 1.0 and 1.5 bar on the gauge and top up if necessary.

Find a Gas Safe engineer

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

Gas Safe Register →

Ariston models that show the Overheating fault code

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

Source

Ariston Overheating 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