BoilerFaultCodesYour boiler has stopped working because the water pressure inside 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: Pressure on the gauge is reading below 0.5 bar. Check for leaks, expansion vessel volume, and water pressure switch wiring/continuity.
What causes this fault?
This fault occurs when the internal water pressure drops below the minimum level required for the boiler to circulate heat safely. The most common cause is a slow leak from a radiator valve or pipework, but it can also happen if air was recently bled from the radiators without topping the water back up.
This issue often surfaces when the heating is first turned on in autumn, as the system expansion during cooling and heating cycles can expose small leaks or reveal pressure loss from the summer months.
DIY fix possible
Locate the silver filling loop underneath or near the boilerSlowly open both taps on the loop until you hear water enteringMonitor the pressure gauge until it reaches 1.5 bar, then close both taps tightly
Find a Gas Safe engineer
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Gas Safe Register →Protect yourself from future repair bills
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Ideal Response FF80 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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