Troubleshooting Guide - Ariston Mgm II evo Instrucciones De Instalacion Y Uso

GB
preparing the boiler for operation
Meaning of the LEDs
GREEN LED (left)
Indicator light off
Indicator light on
Indicator light fl ashing
GREEN LED (centre)
Indicator light off
Indicator light on
Indicator light fl ashing
RED LED (right)
Indicator light off
Indicator light on

Troubleshooting guide

The MGm II and MGm III evo modules is protected against the risk of breakdown by internal checks carried out by the PCB which, if necessary,
will activate a safety shutdown.
The table below shows the possible error codes, their descriptions and the recommended action to be taken in each case:
Error code
7 0 1 Zone 1 heating fl ow temperature sensor fault
7 0 2 Zone 2 heating fl ow temperature sensor fault
7 0 3 Zone 3 heating fl ow temperature sensor fault
7 1 1 Zone 1 heating return temperature sensor fault
7 1 2 Zone 2 heating return temperature sensor fault
7 1 3 Zone 3 heating return temperature sensor fault
7 2 2 Zone 2 overheating
7 2 3 Zone 3 overheating
4 2 0 BUS BridgeNet® supply overload
50
Main supply OFF
Main supply ON
Main supply ON, operation in manual mode
No BUS BridgeNet® communication
BUS BridgeNet® communication present
BUS BridgeNet® communication initialisation
No operating faults
Presence of one or more operating faults
Description Recommended action
Check the connection of the sensor concerned.
Check the continuity of the sensor.
Replace the sensor if necessary.
Check for the shunt and its connection to the "ST2" terminal block
on the module
OR Check the maximum heating temperature setting for Zone 2
(parameter 525).
Check the connection of the safety thermostat to the "ST2" termi-
nal block on the module.
Check for the shunt and its connection to the "ST3" terminal block
on the module
OR Check the maximum heating temperature setting for Zone 2
(parameter 625).
Check the connection of the safety thermostat to the "ST3" termi-
nal block on the module.
A "BUS supply overload" error may appear when three or more
devices supplying power to the BUS are connected to the system.
Example: boiler + hydraulic module + solar pump unit, etc. To avoid
this risk, the microswitch (1) on the electronic PCB of one of the
connected devices (not the boiler) must be switched from ON to
OFF.
O N
1 2
O N
1 2