BoilerFaultCodesWhat the manual says
Manufacturer manualOutdoor Unit, No Water Flow, Error
From this model's manual
Verified against the Ideal Hp290 installation & service manual.
What causes this fault?
This fault occurs when the system detects that water isn't moving through the outdoor unit at the required speed to safely exchange heat. The most common reasons are a build-up of debris or sludge blocking the internal filter, a failure of the main circulation pump, or trapped air pockets within the pipework. When the water stops moving, the unit shuts down to prevent the refrigerant system from overheating or freezing.
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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