BoilerFaultCodesWhat the manual says
Manufacturer manualInsufficient water pressure in the system
What causes this fault?
This fault occurs when the internal water pressure drops below the minimum level required for the boiler to fire up safely. The most common reasons are a slow leak hidden somewhere in your pipework or radiators, or because you recently bled your radiators without topping the system back up.
This issue often appears when you turn your heating back on for the first time in autumn, as cooling pipes can contract and reveal small leaks or pressure drops.
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.
Avoid the next call-out bill
A cover plan would handle faults like 04: no call-out fees, no surprise bills.
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