What the manual says
Manufacturer manualSystem waiting, primary flow temperature above setpoint
From this model's manual
Verified against the Worcester Bosch/Worcester Bosch Greenstar 12i System installation & service manual.
DIY fix possible
Check that at least two radiator valves are fully openEnsure the room thermostat is turned up high enoughWait for the boiler to return to normal operation automaticallyIf the code persists, check that the pump is not seized
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Related fault codes
All 65 fault codes on the Greenstar 27i System Compact ErP
Seeing a different code? Every code this model can display, in one place.