ER 03 + RESET High

Johnson Starley ER 03 + RESET Fault Code

Also written as ER03RESET — same fault.

The Johnson Starley ER 03 + RESET fault code means: your boiler has stopped running as a safety precaution and needs a manual reset to attempt to restart.. It appears on 1 Johnson Starley model in our database.

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: Generic lockout
Typical repair cost £100-350 (including labour)

DIY fix possible

Press and hold the 'Reset' button on the control panel for three seconds.Wait for the boiler to complete its restart sequence.Ensure your gas supply is active (check other gas appliances like a hob).

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Johnson Starley models that show the ER 03 + RESET fault code

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

Source

Johnson Starley ER 03 + RESET fault code information on this page is sourced and cross-checked against the official Johnson Starley service / installation manuals for each affected model.

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