BoilerFaultCodesYour boiler has detected that the water pressure is either too low or the sensor that measures it is not working correctly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Incorrect system water pressure – possible cause is pressure too low or sensor damaged – the system may need filling or check the sensor
What causes this fault?
This fault occurs when the boiler detects that there isn't enough water inside the system to operate safely. The most common reason is a slow leak from a radiator valve or a pipe joint, but it can also happen if you have recently bled your radiators and haven't topped the pressure back up.
This fault is often seen at the start of autumn when homeowners turn their heating back on for the first time after the summer break.
DIY fix possible
Check the pressure gauge on the front of the boiler; it should ideally be between 1 and 1.5 bar.Locate the filling loop (usually a silver flexible hose) underneath or near the boiler.Slowly open the valves until you hear water entering and the pressure gauge rises to 1.2 bar, then close the valves tightly.Reset the boiler to clear the fault code.
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A boiler cover plan would cover faults like F35 — no call-out fees, no surprises.
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Ferroli Modena HE 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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