Medium
F.75 on Glow-worm Essential

Your boiler is struggling to detect the water pressure inside the system because the sensor is not sending a clear signal, which prevents the heating from starting reliably.

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

Fault:Pressuresensor

Shared across the Essential range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s 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 fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

All 83 fault codes on the Essential

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

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