BoilerFaultCodesWhat the manual says
Manufacturer manualLow water pressure. Fill central heating system, pressure 0.7bar min.
What causes this fault?
This fault occurs when the water level inside your central heating system drops too low for the boiler to operate safely. It is usually caused by a small leak in the pipework or radiators, or because the air cushion inside the expansion vessel has depleted over time.
This issue often surfaces in autumn when the heating is turned on for the first time after summer, as the change in temperature can highlight existing 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 Red neon on fascia: no call-out fees, no surprise bills.
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All 7 fault codes on the Fuelsaver Complheat 40 55
Seeing a different code? Every code this model can display, in one place.
Related guides you might find useful
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Read →What pressure should my boiler be?
1 to 1.5 bar when cold on most UK boilers, from the manuals.
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