High
Reset neon is lit on Glow-worm Micron 50FF

Your boiler has automatically shut down for safety reasons, likely because it got too hot or experienced a brief power interruption.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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.

What the manual says

Manufacturer manual

Failure of electrical supply or safety temperature limiter operates. Turn control knob to '0' and back again to reset.

From this model's manual
Verified against the Glow Worm/Glow Worm Micron 50ff installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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All 23 fault codes on the Micron 50FF

Seeing a different code? Every code this model can display, in one place.

Burner LitBurner Lit LEDBurner OnBurner On neon offIlluminated reset lightLED 1LED 1 (RESET) Constant LightLED 1 Fast Flashing (8Hz)LED 1 Slow Flashing (2Hz)LED 2LED 2 Burner LitLED 2 Fast Flashing (8Hz)NEON1NEON2NEON3NEON4NEON5NEON6Reset LED is litReset lightReset Light / OverheatSoftware Error

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