Bosch BSS250E-2 Installation And User Manual page 23

Other forms of Electrical connections for solar may result in unintended operation of the
system.
STANDARD WIRING CONFIGURATION
Electrical installation of solar storage tank with circuit breaker only.
For electric Solar boost applications only L1
For Gas Solar boost applications no electrical connection is made to the Solar tank.
Wiring diagram
L1
N
Thermostat
PE
Element
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