ER 18 + RESET High

Johnson Starley ER 18 + RESET Fault Code

Also written as ER18RESET — same fault.

The Johnson Starley ER 18 + RESET fault code means: your boiler has stopped working because water is not moving through the system properly, which could be due to a blockage or a pump issue.. 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: No water circulation fault
Typical repair cost £150-350 (including labour)

DIY fix possible

Check that all radiator valves are fully openEnsure the system pressure is between 1.0 and 1.5 barCheck for any visible leaks around the unit or pipeworkPress and hold the reset button to see if the error clears

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Johnson Starley models that show the ER 18 + RESET fault code

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

Source

Johnson Starley ER 18 + 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