Bosch Installation Manual

Product Description

Greenstar – 6721822579 (2021/01)

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.