BoilerFaultCodesYour boiler has detected that the water pressure in your heating system is falling much faster than normal, which usually indicates a significant leak or a fault with the pressure sensor.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Pressure drop in heating system too rapid
What causes this fault?
This fault occurs when the boiler's internal sensor detects a sudden and significant loss of water pressure within a short timeframe. The most common reason is a major leak in your radiators or pipework, though it can also be triggered by a failing component inside the boiler that is incorrectly reading the pressure levels.
This fault is more common in autumn when homeowners first turn their central heating back on after summer, as the change in temperature and pressure can expose weak seals or pinhole leaks.
DIY fix possible
Check all visible radiators and pipes for signs of water leaksTop up the system pressure using the internal filling link to between 1 and 1.5 barMonitor the pressure gauge to see if it drops rapidly again after refilling
Find a Gas Safe engineer
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A boiler cover plan would cover faults like 2970 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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