BoilerFaultCodesWhat the manual says
Manufacturer manualService message: Check water pressure. A service message is activated. Check the water pressure.
What causes this fault?
This message is triggered when the internal sensor detects that the system's water pressure has dropped below the ideal operating level. It is usually caused by a small leak in the pipework, air being bled from radiators, or a component like the expansion vessel losing its charge. Because the pressure is low, the boiler is struggling to circulate heat effectively around your home.
This warning is more frequent in autumn and winter when homeowners turn their heating back on after a long break or bleed their radiators to remove cold spots.
DIY fix possible
Locate the filling loop valves underneath the boilerSlowly open both valves until you hear water movingMonitor the pressure gauge until it reaches between 1.0 and 1.5 bar, then close both valves tightly
Avoid the next call-out bill
A cover plan would handle faults like S.76: no call-out fees, no surprise bills.
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Related fault codes
All 146 fault codes on the ecoTEC Pro 24
Seeing a different code? Every code this model can display, in one place.