Bosch Greenstar Series Installation And Service Instructions For Contractors page 15

Key to Fig. 7:
[1] Ignition transformer
[2] Boiler high limit dial
[3] 120 VAC connection
[4] DHW tank primary pump or 3-way valve
[5] External heating pump for unmixed heating circuit (secondary
circuit) 5 or DHW recirculation pump
[6] Fuse T 6.3 A (120 VAC)
[7] DHW thermostat
[8] External safety high limit or low water cut off (LWCO)
[9] BUS connection, e.g. heating control
[10] Room thermostat – dry contact
[11] Outdoor temperature sensor
[12] Code plug
[13] Diagnostic interface
[14] ON/OFF switch
[15] Gas valve
[16] Fan
[17] Flue gas temperature limiter
[18] Supply temperature sensor
[19] Flame rod electrode
[20] Ignition electrode
[21] Boiler block temperature limiter
[22] DHW tank temperature sensor (NTC)
[23] Boiler circulator
[24] Additional supply temperature limiter
[25] External system supply temperature sensor
1) Set the service function 1.F,  page 57.
2) Set the service function 5.E,  page 59.
Greenstar – 6721822579 (2021/01)
1)
2)
Product Description
15