BoilerFaultCodesYour boiler has stopped working because the water pressure inside the system is too low for it to operate safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: System pressure low - Go to Frame 86
What causes this fault?
This fault occurs when there isn't enough water circulating through your heating system to safely transfer heat. The most common reasons are a slow leak in the pipework or radiators, or air being released from the system through the vents. Without sufficient water pressure, the boiler disables itself to prevent the internal heat exchanger from overheating and sustaining damage.
This issue is frequently seen in autumn when homeowners turn their heating back on for the first time, often discovering that pressure has slowly dropped over the summer months.
DIY fix possible
Locate the filling loop (a flexible silver hose) underneath or near your boiler.Open both valves slowly to allow water into the system while watching the pressure gauge.Close both valves firmly once the needle reaches between 1.0 and 1.5 bar.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like system pressure gauge below 0.5 bar — no call-out fees, no surprises.
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Ideal Response 80 100 120 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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