BoilerFaultCodesTechnical description
Low water level
What causes this fault?
This fault occurs when the internal sensors detect that the system's water pressure has dropped below the minimum level required for safe operation. The most common reason is a slow leak somewhere in your radiators or pipework, though it can also happen if you have recently bled your radiators without topping the pressure back up.
This issue often surfaces in autumn when homeowners turn their heating back on for the first time, as the change in temperature can highlight minor leaks or pressure loss during the summer.
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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