BoilerFaultCodesTechnical description
Check system pressure – refill if necessary. If fault reoccurs, contact a heating engineer.
What causes this fault?
This fault occurs when the internal sensor detects that there isn't enough water volume within the central heating circuit to safely transfer heat. The most common reasons are a slow leak from a radiator valve or the pressure dropping naturally after you have recently bled air from your radiators.
This fault is frequent in autumn when homeowners turn their heating back on for the first time and find the pressure has dropped over the summer 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.
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