BoilerFaultCodesTechnical description
No or low system water pressure. system pressure less than 0.5bar
What causes this fault?
This fault occurs when the internal pressure sensor detects that the water level inside your heating system has dropped below a safe operating limit. The most common reason is a slow leak from a radiator valve or pipework, though it often happens after you have bled your radiators and haven't topped the pressure back up.
This issue is frequently seen in autumn when homeowners turn their heating back on for the first time or bleed their radiators to remove air pockets.
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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