BoilerFaultCodesTechnical description
Circulation fault (dry fire).
What causes this fault?
This fault occurs when the boiler's internal sensors detect the temperature rising far too quickly, often because there is no water flow to carry the heat away. The most common reasons are a failed circulation pump that can no longer push water through the pipes, or a blockage caused by a build-up of debris or limescale. In some cases, it may also be caused by air trapped in the system or a blockage in the heat exchanger.
This fault is frequently seen in autumn when the heating is turned on for the first time after summer, as pump components can seize up 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.