From RegConfig in Connect mode via cable or Web Connection mode it is possible to see all the available alarms by entering the Alarms page:
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Once the alarm has been resolved, the red light turns off without any further operations.
Attention
Errors from 16 to 23 (Circuit limit temperature) must be reset by switching the heat/cold enable off and on again or by switching off and on the power supply to the REG.
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BUS ERRRORS
The System provides a bus error signal by turning ON the yellow led on the REG-DIN-8.
If both alarms (red light on) and bus errors (yellow light on) are present on the REG-DIN-8, it is necessary to solve the bus error first as it could be the cause of the alarm. For example, if there were a communication problem with the REG-IOA expansion module to which the TP probe of zone 1 is connected there would be both a bus error (because the REG-DIN-8 and the REG-IOA do not communicate ), but also alarm 24 relating to the failure to read the temperature of zone 1. Once the bus error is resolved, the alarm is also resolved.
For more info about bus error trouble shooting see BUS REG WIRING BEST PRACTICE.