BoilerFaultCodesYour boiler has tried to start up but detected that there is no water inside the system to heat safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Dry fire: Boiler has been fired without water
What causes this fault?
This fault occurs when the boiler's internal sensors detect a dangerous lack of water pressure or flow during the ignition process. The most common reason is a leak somewhere in your central heating system, or a failure of the pump to move water through the heat exchanger, leading to a risk of the unit overheating.
This fault often appears in autumn when the heating is turned on for the first time after summer, as small leaks may have gradually lowered the pressure over several months.
DIY fix possible
Check the pressure gauge on the boiler or piping; it should be between 1 and 1.5 bar.If the pressure is low, use the external filling loop valves to top the system up with water.Ensure all radiator valves and boiler isolation valves are fully open.Once the pressure is corrected, press the reset button on the control panel.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like 4 — no call-out fees, no surprises.
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Potterton Envoy System 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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