High
F.83 on Glow-worm Easicom3 System

Your boiler has detected that there is not enough water circulating inside the system to carry heat away safely.

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

Fault: Dry fire - When the burner starts, the temperature change recorded by the flow or return temperature sensor is non-existent or too small: Insufficient water in the product, flow or return temperature sensor incorrectly attached to the pipe

From this model's manual
Verified against the Glow Worm/Glow Worm Easicom3 System installation & service manual, page 43.
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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Related fault codes

F.22View →F.75View →

All 90 fault codes on the Easicom3 System

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

F.00F.01F.10F.11F.13F.20F.22F.23F.24F.25F.27F.28F.29F.32F.49F.61F.62F.63F.64F.65F.67F.68F.70F.71F.72F.73F.74F.75F.77F.78F.84F.85F.86F.87F.88F.89F.97F22P.01P.02P.03P.04P.05P.06P.07S.0S.01S.02S.03S.04S.05S.06S.07S.08S.10S.11S.13S.14S.15S.16S.17S.20S.21S.22S.23S.24S.25S.26S.27S.28S.30S.31S.32S.33S.34S.39S.41S.42S.46S.53S.54S.88S.91S.96S.97S.98S.99S.108S.109

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