BoilerFaultCodesTechnical description
The boiler will not operate. The heating system will need to be re-pressurised to at least 0.7bar
What causes this fault?
This fault occurs when there isn't enough water circulating inside your heating system to safely operate the boiler. The most common reasons are a slow leak from a radiator valve or pipework, or air being released from the system through the radiators. Over time, this loss of water lowers the internal pressure until the boiler's safety sensors shut the unit down to prevent internal damage.
This issue is more frequent in autumn or early winter when the heating is turned on for the first time after summer, as the change in temperature can reveal small leaks or trapped air.
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.