BoilerFaultCodesYour boiler has too much water inside it, causing the pressure to reach a dangerously high level where the safety valve must release water.
Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now — this fault can be dangerous if ignored.
Technical description: A pressure of 3 or greater indicates a fault. The safety pressure relief valve will operate.
What causes this fault?
This fault occurs when the internal water pressure becomes too high, often because the expansion vessel has lost its air charge and can no longer absorb the natural expansion of heated water. It can also be caused by a filling loop being left slightly open, which allows water from the mains to constantly leak into the system, or a split heat exchanger allowing cross-contamination.
This issue is most frequently noticed in winter when the heating is first turned on, as this is when the water undergoes the most expansion and puts the most stress on the expansion vessel.
DIY fix possible
Check that the filling loop valves are tightly closed.Bleed water from a radiator using a bleed key to lower the pressure gauge to 1.5 bar.Monitor the gauge to see if the pressure rises again on its own.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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A boiler cover plan would cover faults like Pressure Gauge 3 or greater — no call-out fees, no surprises.
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Potterton Performa 24 Eco 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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