Glow Worm Energy 25c fault F.32: Boiler displaying F
Published 12 May 2026 · Generated by BoilerTag's diagnostic AI from an engineer's real-world submission
One of 13 real-world fault checklists on BoilerTag, across 5 boiler makes.
Most likely cause
The Glow Worm Energy 25c displaying fault code F.32, with the fan cycling erratically and making a struggling humming noise, indicates an 'air pressure issue' or 'fan speed outside the tolerance values'. This is often caused by a fan malfunction, blocked air intake/flue, or a faulty Hall sensor. The intermittent nature becoming constant suggests a component is failing completely.
The engineer's report
A gas engineer submitted this case through BoilerTag's free fault diagnostic tool, working on a Glow Worm Energy 25c displaying fault code F.32. They described the behaviour they were seeing on site as follows:
“Boiler displaying F.32, with the fan cycling on and off erratically. No hot water or heating is being produced, and the fan sounds like it's struggling to spin up, making a low humming noise before cutting out. This has been happening intermittently for the last couple of weeks, but now it's constant.”
Before requesting the AI diagnostic, the engineer had already worked through the following checks:
“Checked the multiplug on the fan and the PCB, both appear to be seated correctly. Visually inspected the fan for any obvious obstructions, but none were apparent. The cable harness also appears intact at a first glance.”
BoilerTag's diagnostic AI then cross-checked manufacturer documentation and common trade knowledge to produce the prioritised checklist below.
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Diagnostic checklist
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Commonly failed parts
- Glow Worm Energy 25c Fan Assembly
- Glow Worm Energy 25c PCB (if other checks confirm it's faulty)
- Glow Worm Energy 25c Air Pressure Switch (if diagnosed as faulty)
More Glow Worm fault codes
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