BoilerFaultCodesYour boiler has stopped working because the water pressure inside the system is too low.
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
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 safely. The most common reasons for this are a leak somewhere in the pipework or radiators, or because you have recently bled your radiators without topping the water back up.
This fault is more common in autumn and winter when the heating is first turned back on, as the increased pressure of hot water can highlight small leaks or air pockets that developed while the system was idle.
DIY fix possible
Locate the filling loop (usually a silver flexible hose) under or near the boiler.Slowly open the valve or valves until you hear water flowing into the system.Watch the pressure gauge and close the valves once the needle reaches 1.5 bar.
Find a Gas Safe engineer
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Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like F37 — no call-out fees, no surprises.
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Ferroli Bluehelix Tech 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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