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.
Technical description: ALTERNATING 'H' '2' GO TO FRAME 91
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Gas Safe Register →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