BoilerFaultCodesYour boiler has detected that the water pressure in the system is too low or the pressure sensor settings are incorrect, causing the unit to stop working.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Low water pressure in heating system – parameter is adjusted wrong
What causes this fault?
This fault occurs when the boiler detects that there isn't enough water pressure to safely circulate heat around your home. The most common reason is a slow leak in the radiator system or air being released from the pipework, causing the pressure to drop below the minimum safety threshold.
This issue often appears in autumn when the heating is turned on for the first time after summer, as the change in temperature can highlight small leaks or trapped air.
DIY fix possible
Check the pressure gauge; it should ideally be between 1.0 and 1.5 bar.Locate the filling loop (usually a silver flexible hose) under the boiler.Open both valves slowly to allow water into the system until the gauge reaches 1.2 bar, then close them tightly.
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A boiler cover plan would cover faults like rE02 — no call-out fees, no surprises.
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Could it be time for a new boiler?
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