BoilerFaultCodesYour boiler has detected that the water pressure is too low for it to operate safely, which usually means the system needs more water.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Low Pressure Error
What causes this fault?
This fault occurs when the internal sensor detects that the system's water pressure has dropped below the minimum level required to circulate heat safely. The most common reasons are a slow leak in the radiator valves or pipework, or simply needing to top up the water levels after bleeding your radiators.
This fault is more common in autumn when homeowners turn their heating back on for the first time, as small leaks may have developed or the system pressure may have settled during the summer months.
DIY fix possible
Locate the metal braided filling loop underneath or near the boilerOpen the valves slowly until you hear water flowing and the pressure gauge reaches 1.5 barClose both valves tightly and reset the boiler
Find a Gas Safe engineer
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Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like P0 — 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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