High
H 2 on Ideal Isar System

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.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

H 1View →H 3View →

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