BoilerFaultCodesTechnical description
If the pressure falls below 0.5, this may indicate a leak on the central heating system.
What causes this fault?
This fault occurs when there isn't enough water circulating inside your heating system to safely transfer heat, triggering a safety sensor to shut the boiler down. The most common reasons are a slow leak from a radiator valve or pipework, or the pressure relief valve becoming faulty and letting water escape the system.
This issue is more frequent in autumn when the heating is turned back on after a long break, as changing temperatures can cause seals to weep or highlight existing pressure drops.
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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