r1 Low

Worcester Bosch r1 Fault Code

Also written as R1 — same fault.

The Worcester Bosch r1 fault code means: your boiler is currently resetting its internal settings back to the way they were when it first left the factory.. It appears on 3 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: Resetting service functions 0.0 to 4.9 to their factory settings

What causes the Worcester Bosch r1 fault?

This code appears when the boiler's control system has been manually triggered to clear custom adjustments and return to its original manufacturer configuration. It is usually the result of an engineer or homeowner navigating the menu to restore default performance levels or troubleshooting a software glitch. While the code is active, the boiler is simply recalibrating its internal logic to ensure it operates exactly as intended from the factory.

DIY fix possible

Wait for the boiler to complete the reset process naturallyOnce finished, the display should return to the normal temperature readingRe-adjust your heating and hot water temperature dials to your preferred levels if they have changed

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Worcester Bosch models that show the r1 fault code

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

Source

Worcester Bosch r1 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