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5271 Customer Alarm Heating circuit 1
high flow temperature
Alarm when sensor T0 > "Max. flow
temperature" set point value + 5 degrees, for
10 seconds.
The alarm is blocked for 5 minutes after a
DHW cycle.
Defective T0 sensor.
With sensor disconnected from the installer board,
compare sensor resistans to table values for T0
found in the documentation.
Low flow in heating system. Clean filter ball on return pipe. Check adjustment
valves and thermostats for the heating system.
The system is in heating mode but the
diverter valve has not switched over to
DHW.
Check that 230 V is available on terminal 53 (VW1)
during DHW mode. If 230 V during DHW mode,
replace the motor/cable for the diverter valve. If
voltage is missing during DHW mode, replace the
installer module