H 2 High

Ideal H 2 Fault Code

Also written as H2 — same fault.

The Ideal H 2 fault code means: your boiler's internal sensor that monitors the water temperature returning to the unit is malfunctioning, which is causing the system to stop working as a safety precaution.. It appears on 3 Ideal models 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: ALTERNATING 'H' '2' GO TO FRAME 91
Typical repair cost £120-220 (including labour)

Engineer required

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

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Ideal models that show the H 2 fault code

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

Source

Ideal H 2 fault code information on this page is sourced and cross-checked against the official Ideal service / installation manuals for each affected model.

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