High
ER 10 + reset on Biasi Riva Compact 24S

Your boiler has detected low water pressure in the system, which is preventing it from firing up to provide heat or hot water.

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.

Technical description

N/A

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.

Find a Gas Safe engineer
Search the official register →

Related guides you might find useful

Boiler keeps losing pressure

Six most common causes of dropping pressure.

Read →

No hot water but heating works

Almost always a stuck diverter valve on combis.

Read →

Low pressure — repressurise guide

Step-by-step using the filling loop.

Read →