BoilerFaultCodesYour boiler has detected that the water pressure in the system is too low to run safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Low system pressure neon
What causes this fault?
This fault occurs when the water pressure inside your heating system drops below the minimum level required for the boiler to operate. The most common reasons are a slow leak from a radiator valve or pipework, or the pressure being manually released too far after bleeding your radiators.
This issue is frequently seen in autumn when homeowners turn their heating back on for the first time and discover the pressure has naturally dropped over the summer months.
DIY fix possible
Locate the filling loop (usually a silver flexible hose) underneath the boiler.Slowly open the small valves on the hose until you hear water moving.Watch the pressure gauge and close the valves once the needle reaches between 1 and 1.5 bar.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like K — no call-out fees, no surprises.
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Ideal Response FF80 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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