i19 Low

Worcester Bosch i19 Fault Code

Also written as I19 — same fault.

The Worcester Bosch i19 fault code means: your boiler is simply reporting the current status of your heating timer settings rather than indicating a technical fault.. 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: Time inputs - This indicates the status of the optional fascia mounted controls: 0 = CH off, DHW off, 1 = CH off, DHW on, 2 = CH on, DHW off, 3 = CH on, DHW on

DIY fix possible

Check your external programmer or timer dial on the front of the boilerAdjust the settings to your desired schedule for central heating and hot waterIf the code persists despite settings being active, toggle the timer switch off and on to reset the display

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Worcester Bosch models that show the i19 fault code

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

Source

Worcester Bosch i19 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