BoilerFaultCodesTechnical description
Primary flow temperature exceeded 95°c
What causes this fault?
This fault occurs when the water inside the boiler cannot move away from the burner fast enough, causing it to reach a dangerously high temperature. The most common reasons are a failed internal pump that isn't pushing the water around, or a blockage caused by a build-up of sludge and debris in the system. When this heat spike is detected, the boiler shuts down immediately as a safety precaution to prevent internal damage.
This fault is more common in autumn when heating is turned on for the first time after summer, as pump components can seize 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.