BoilerFaultCodesYour boiler has detected that there is not enough water circulating through the system 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: pump has run dry
What causes this fault?
This fault occurs when the boiler's internal sensors detect air pockets or a significant drop in water pressure, preventing the pump from moving water around. The most common cause is a leak in the system or radiators that have recently been bled, leaving the boiler with insufficient water to operate safely. Without enough water to act as a lubricant and coolant, the pump 'runs dry' and the system shuts down to prevent heat damage.
This issue is frequently seen in autumn when homeowners turn their heating back on for the first time and discover pressure has dropped over the summer months.
DIY fix possible
Check your boiler's pressure gauge to see if it is below 1 barLocate the filling loop (usually silver braided hoses under the boiler)Slowly open the valves until the pressure reaches 1.5 bar, then close them tightly
Find a Gas Safe engineer
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A boiler cover plan would cover faults like A1 — no call-out fees, no surprises.
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Worcester Bosch Greenstar 30HE 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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