BoilerFaultCodesYour boiler has too much water inside it, which is causing the safety valve to leak or trigger to protect the system from bursting.
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 there is too much water pressure in the system, often caused by the filling loop being left slightly open or a internal leak between the domestic hot water and central heating sides. It can also happen if the expansion vessel has lost its air charge, meaning there is no room for water to expand as it heats up. As a result, the pressure rises rapidly until it forces the safety valve to open and discharge water.
This issue often becomes apparent in winter when the heating is first turned on, as the increased heat causes water to expand and reveals a failing expansion vessel.
DIY fix possible
Check that the filling loop valves (the silver braided hose underneath) are tightly closed.Locate a radiator and use a bleed key to release water through the air vent into a jug until the pressure gauge falls between 1 and 1.5 bar.Monitor the gauge to see if the pressure starts rising again on its own.
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 Pressure of 3 or greater — no call-out fees, no surprises.
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Potterton Performa 24 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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