BoilerFaultCodesWhat the manual says
Manufacturer manualLow water or no water in appliance | Cause: No water in system, Pump defective, Pump lead defective
What causes this fault?
This fault occurs when the boiler's internal sensors detect that the system pressure has dropped too low for it to heat up safely. The most common reason is a slow leak in the radiators or pipework, but it can also be triggered if the circulation pump has failed and is no longer moving water through the heat exchanger.
This issue is frequently seen in autumn when homeowners turn their heating back on for the first time, as small leaks or trapped air can cause the pressure to dip over the summer 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.
Avoid the next call-out bill
A cover plan would handle faults like F.22: no call-out fees, no surprise bills.
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