BoilerFaultCodesTechnical description
Pump does not run when central heating demand is active
What causes this fault?
This fault occurs when the boiler's internal computer tries to send power to the pump but detects no movement or electrical response. The most common reason is that the pump has seized due to a build-up of debris in the system water or the internal motor has reached the end of its lifespan. In some cases, a loose connection or a fault on the main control board prevents the electrical signal from reaching the pump at all.
This fault is frequently seen at the start of autumn when the heating is turned on for the first time after being idle all summer, as pumps are prone to seizing 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.