BoilerFaultCodesYour boiler has stopped working because the water pressure in the system has dropped too low 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: This may indicate a leak on the central heating system.
What causes this fault?
This fault occurs when there isn't enough water circulating inside your heating system to safely transfer heat, triggering a safety sensor to shut the boiler down. The most common reasons are a slow leak from a radiator valve or pipework, or the pressure relief valve becoming faulty and letting water escape the system.
This issue is more frequent in autumn when the heating is turned back on after a long break, as changing temperatures can cause seals to weep or highlight existing pressure drops.
DIY fix possible
Locate the silver filling loop underneath the boilerSlowly open both taps/levers on the filling loop until you hear water movingClose both taps tightly once the pressure gauge on the front of the boiler reaches between 1.0 and 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 below 0.5 — 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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