201 O Low

Worcester Bosch 201 O Fault Code

Also written as 201O — same fault.

The Worcester Bosch 201 O fault code means: your boiler is simply letting you know that it is currently busy heating up the water for your taps or shower.. It appears on 10 Worcester Bosch models 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: Boiler in hot water mode

What causes the Worcester Bosch 201 O fault?

This code appears when the boiler detects a demand for hot water from a tap or shower, causing it to divert its energy away from the radiators. It is a normal internal message indicating that the burner is firing to heat the water for your domestic use. Once you turn the tap off, the boiler will return to its previous state or go into standby.

DIY fix possible

This fault may be fixable without an engineer. Check your manual first.

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Worcester Bosch models that show the 201 O fault code

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

Source

Worcester Bosch 201 O 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