High
F.73 on Glow-worm Energy7 System

Your boiler is unable to read the water pressure level because the sensor responsible for checking it is faulty or disconnected, preventing the boiler from starting 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: Water pressure sensor not connected or has short-circuited

From this model's manual
Verified against the Glow Worm Energy7 System installation & service manual, page 51.
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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F.74View →F.22View →

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