BoilerFaultCodesYour boiler has detected that there is not enough water in the system to operate safely and has shut down to prevent damage.
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
What causes this fault?
This fault occurs when the internal pressure sensor detects that the system water level has dropped below the minimum required for safe operation. The most common reason is a slow leak somewhere in your radiators or pipework, or a failure in the components that regulate pressure, such as the expansion vessel. Without enough water, the boiler cannot circulate heat effectively and shuts down to prevent the main heat exchanger from overheating.
This issue is frequently seen in autumn when homeowners turn their heating back on after the summer, as the change in temperature can highlight small leaks or a loss of pressure in the expansion vessel.
DIY fix possible
Locate the filling loop (usually a silver flexible hose) underneath your boiler.Slowly open the small valves at either end of the hose until you hear water entering the system.Monitor the pressure gauge and close the valves once the needle reaches between 1.0 and 1.5 bar.Reset the boiler to clear the fault code.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like E08 — no call-out fees, no surprises.
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Ravenheat CS 80/90, WH System, WH 80/90 is discontinued — time for a new one?
Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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