BoilerFaultCodesTechnical description
Status external heating pump error
What causes this fault?
This fault occurs when the boiler sends power to the external pump but detects that water isn't moving through the system as expected. The most common reason is that the pump has seized due to a build-up of debris or internal mechanical failure, preventing it from spinning. In some cases, it can also be triggered by a communication error between the boiler's control board and the pump's electrical wiring.
This issue frequently appears at the start of autumn when heating systems are turned back on after being dormant all summer, which can cause the pump to seize.
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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