BoilerFaultCodesTechnical description
Insufficient system pressure - the system pressure is low
What causes this fault?
This fault occurs when the water pressure inside your central heating system drops below the minimum level required for the boiler to operate. The most common reasons for this are a leak somewhere in the pipework or radiators, or the air pressure in the expansion vessel needing to be topped up by an engineer.
This issue is more frequent in autumn when people turn their heating back on after summer, as the change in temperature can highlight minor leaks or a loss of pressure in the system.
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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