BoilerFaultCodesTechnical description
Loss of system pressure, i.e. less than 0.7bar. (Display will repeatedly flash '1' then '2')
What causes this fault?
This fault occurs when the water pressure inside your heating system drops below a safe level, causing the boiler to shut down to prevent damage. The most common reasons are a slow leak from a pipe or radiator, or a loss of air in the expansion vessel which helps manage pressure changes. If you have recently bled your radiators, this can also cause the pressure to drop enough to trigger this code.
This issue is frequently seen at the start of autumn when homeowners turn their heating back on after the summer and find that small, slow leaks have lowered the pressure over time.
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.