i22 Low

Worcester Bosch i22 Fault Code

Also written as I22 — same fault.

The Worcester Bosch i22 fault code means: your boiler is displaying a specific tracking code that identifies its power configuration, which usually appears after an internal control module has been replaced or reset.. It appears on 1 Worcester Bosch model in our database.

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description: HCM number - HCM last 3 digits displayed: 391 = 12/18 kW, 390 = 18/25 kW, 301 = 25/32 kW

Engineer required

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

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Worcester Bosch models that show the i22 fault code

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

Source

Worcester Bosch i22 fault code information on this page is sourced and cross-checked against the official Worcester Bosch service / installation manuals for each affected model.

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