High
S.54 on Glow-worm Energy7 System

Your boiler has paused because the water pressure is too low or the water is not circulating properly around your heating system.

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

Waiting period: Water deficiency in the circuit (flow/return spread too large)

From this model's manual
Verified against the Glow Worm Energy7 System installation & service manual, page 50.
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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