BoilerFaultCodesTechnical description
Primary system water pressure too low
What causes this fault?
This fault occurs when the pressure within your central heating system drops below a safe operating level, usually because water has escaped the circuit. The most common reasons for this are a leak in the radiator valves or pipework, or air being released from the system through recent bleeding of the radiators.
This fault is frequently seen in autumn when homeowners turn their heating back on for the first time after summer, revealing pressure drops that occurred during the warmer months.
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.
Find a Gas Safe engineer
Search the official register →