BoilerFaultCodesTechnical description
Insufficient water pressure in the system (less than 0.5 bar)
What causes this fault?
This fault occurs when the internal sensors detect that the water level has dropped below the minimum safe operating limit. The most common reason is a slow leak from a radiator valve or joint, though pressure can also drop if you have recently bled your radiators without topping the system back up.
This issue is more frequent in autumn when homeowners turn their heating back on after the summer and discover pressure has gradually bled away over several months.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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