BoilerFaultCodesYour boiler has detected that the water pressure is too low to operate safely, causing it to lock out.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Is there 230V~ between K1 and N? Check 0.2 Bar of water pressure is available at boiler. If ok, Replace water pressure switch.
What causes this fault?
This fault occurs when the internal sensors detect that there isn't enough water pressure inside the system to safely heat your home. The most common reason is a slow leak in the pipework or radiators, though it can also happen if the system was recently drained and not refilled correctly. Without sufficient water, the boiler shuts down to prevent the internal components from overheating and sustaining permanent damage.
This issue often appears in autumn when homeowners turn their heating back on for the first time, as the system may have lost pressure gradually over the summer months.
DIY fix possible
Check the water pressure gauge on your system.If the pressure is below 1.0 bar, use the external filling loop to top up the system to 1.5 bar.Reset the boiler to see if the light clears.
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