BoilerFaultCodesTechnical description
Pump c/w auto air vent & 2 off washers
What causes this fault?
This fault occurs when the boiler's internal pump can no longer move water through the system effectively, often due to a mechanical failure or debris causing the pump to seize. It can also be triggered by a build-up of air within the unit that prevents the pump from gaining the necessary prime to circulate heat. If the pump cannot move the water, the boiler shuts down to prevent the internal heat exchanger from dangerously overheating.
This issue often surfaces in autumn when the heating is turned back on after being idle all summer, as stagnant water can cause pump components 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.