BoilerFaultCodesTechnical description
Insufficient water pressure in the system (less than 0.5 bar)
What causes this fault?
This fault occurs when the water level inside your central heating system drops too low for the boiler to operate safely. The most common reasons are a slow leak from a radiator valve or pipework, or the air being manually bled from radiators without the pressure being topped back up.
This code is particularly common in autumn when homeowners first turn their heating back on after summer, causing old seals to weep or revealing pressures that have slowly dropped during months 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.
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