Installation and service instructions
for contractors
VIESMANN
SDIO/SM1A electronics module
■
In conjunction with the Vitotronic control unit and HMU heat management unit
■
For controlling and regulating a solar DHW heating system
■
Solar functions:
–
With central heating backup
–
With 2nd cylinder preheating
–
With thermostat function
SDIO/SM1A electronics module
6131981 GB
9/2019
Please keep safe.
