Low
S.16 on Glow-worm Ultracom 35 Store

Your boiler's fan is running longer than necessary to clear out exhaust gases, which may temporarily stall the start-up process.

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

fan overrun

From this model's manual
Verified against the Glow Worm Ultracom 2 Cxi installation & service manual, page 52.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

What causes this fault?

This fault occurs when the boiler's internal computer detects that the fan is spinning for too long or at an unexpected time during the ignition sequence. The most common reason is a communication error between the fan and the main control board, or the fan itself beginning to wear out and failing to stop when instructed.

DIY fix possible

Check if the boiler eventually progresses to a normal firing statePress the reset button to clear the status codeMonitor for more persistent fault codes such as F.32

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