BoilerFaultCodesYour boiler has stopped working because the water pressure is too low, often caused by a small leak or air in the radiators.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: If the pressure falls below 0.5, this may indicate a leak on the central heating system.
What causes this fault?
This fault occurs when the sealed water circuit inside your heating system loses enough water to drop below the safe operating limit. The most common reasons are tiny leaks from radiator valves or the automatic air vent, as well as air being released from the system through the radiators. Without enough water pressure, the boiler cannot safely circulate heat and shuts down to prevent internal damage.
This issue is frequently seen in autumn when the heating is turned back on for the first time, as the change in temperature can cause joints to weep or trapped air to move through the pipes.
DIY fix possible
Locate the silver braided filling loop underneath or near the boilerSlowly open the one or two taps on the filling loop until you hear water enteringWatch the pressure gauge and close the taps when it reaches 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 Pressure Gauge below 0.5 — 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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