BoilerFaultCodesTechnical description
Insufficient system water pressure
What causes this fault?
This fault occurs when the water pressure inside your heating system drops below the minimum level required for the boiler to operate safely. The most common reason is a slow leak from a radiator valve or pipework, but it can also happen if you have recently bled your radiators and haven't topped the system back up.
This issue is frequently seen at the start of autumn when homeowners turn their heating back on for the first time or bleed their radiators after months of inactivity.
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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