BoilerFaultCodesTechnical description
No Water Flow, through Outdoor Unit, 10 times in succession
What causes this fault?
This fault occurs when the system detects that water is not moving through the outdoor unit quickly enough to safely transfer heat. The most common reasons include a blockage in the pipework, a faulty internal pump, or a build-up of debris in the system filter that is choking the flow.
This issue is more frequent during the first cold snaps of winter when the system is under higher load and any existing debris or pump sluggishness becomes critical.
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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