BoilerFaultCodesTechnical description
Low water pressure. Fill central heating system, pressure 0.7bar min.
What causes this fault?
This fault occurs when the water level inside your central heating system drops too low for the boiler to operate safely. It is usually caused by a small leak in the pipework or radiators, or because the air cushion inside the expansion vessel has depleted over time.
This issue often surfaces in autumn when the heating is turned on for the first time after summer, as the change in temperature can highlight existing pressure drops.
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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