High
E26 on Keston Qudos 28S

Your boiler has stopped working because the water pressure inside your heating system has dropped too low.

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

The system water pressure is too low. Check the system has water in and, for sealed systems, top up the system water pressure to restore a pressure of between 1 and 2 bar. (Consult your installer for instruction how to top up water pressure - repeated need for restoration of water pressure indicates a system leak which should be investigated)

From this model's manual
Verified against the Keston Qudos 28s installation & service manual, page 38.
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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