BoilerFaultCodesTechnical description
The system needs re-pressurising (check pressure gauge)
What causes this fault?
This fault occurs when the internal water pressure drops below the minimum level required for the boiler to operate safely. The most common reasons are a slow leak hidden somewhere in your radiator system or air being released through a safety valve.
This issue often occurs in autumn when the heating is turned on for the first time after summer, as air pockets and thermal expansion can cause the pressure to fluctuate.
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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