BoilerFaultCodesTechnical description
Safety switch off low water pressure
What causes this fault?
This fault occurs when the internal water pressure drops below the safe operating limit, causing the boiler to shut down to prevent damage to the heat exchanger. The most common reasons for this are a leak somewhere in the central heating pipework or radiators, or simply that the system needs to be topped up after air was bled from the radiators.
This fault is frequently seen in autumn when homeowners turn their heating back on for the first time and discover the pressure has naturally depleted over the summer months.
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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