BoilerFaultCodesYour boiler has stopped working because a control knob is set to a restricted technician mode or the system has detected an internal electronic fault.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: 1) Hot Water knob on a position reserved to the Technician; 2) Fault inside the boiler. Call your Installation/ Servicing company or Glow-worm service.
What causes this fault?
This fault typically occurs when the hot water control dial has been accidentally turned into a specific restricted zone used only by engineers for testing. In other cases, it signifies that the boiler's internal computer is receiving conflicting signals or has suffered a hardware failure. This prevents the system from starting to ensure no damage occurs to the electronic components.
DIY fix possible
Check the hot water temperature knob on the front of the boiler.Ensure the knob is turned to a normal temperature setting and not pointed at the technician/service icon.Restart the boiler by turning the power off and back on to see if the flashing light clears.
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