BoilerFaultCodesTechnical description
Low water–level waiting period
What causes this fault?
This fault occurs when the boiler's internal sensors detect that water isn't moving through the heat exchanger quickly enough to safely carry heat away. The most common reasons are a failing circulation pump that can't push the water round, or a build-up of air and debris that is restricting the flow and causing the temperature to rise too rapidly.
This issue is more frequent in autumn when heating systems are turned back on after summer, as pump components can seize up during long periods of inactivity.
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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