High
28 on Ravenheat Rsf

Your boiler has detected that there is not enough water pressure or movement to operate safely, causing the system to shut down.

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

Failed low water – pressure switch or pump, possible issue with pump, incorrect system pressure or the low water switch pressure needs replacing

From this model's manual
Verified against the Ravenheat Rsf installation & service 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 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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