BoilerFaultCodesYour boiler is struggling to push water around your radiators because an external pump is not working as expected.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: External pump
What causes this fault?
This fault occurs when the boiler detects that an additional external pump, which helps move water through your heating system, has failed or lost electrical power. The most common reason is an electrical fault in the pump itself or a break in the wiring connecting the pump to the boiler's main control board. Without this pump operating, the boiler cannot safely distribute heat, leading it to shut down to prevent overheating.
This fault is frequently seen at the start of autumn when heating systems are turned back on after months of inactivity, which can cause external pump components to seize.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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