Bosch Installation Manual

Product Description
Greenstar – 6721822579 (2021/01)
8
3Product Description
ZBR...-3A appliances are residential boilers for central heating and
loading of an indirect fired DHW tank.
ZWB...-3A appliances are residential combi boilers for central heating
and on demand DHW heating.
The appliances comply with South Coast Air Quality Management
District (SCAQMD) 2012 requirements: (Type-1) 14 Ng/J NO
x
(and/or
20 ppm at 3% O
2
).
3.1 Proper use
The Greenstar boiler is not for use in CSD-1 commercial installation.
The appliance may only be installed in closed loop hot water central
heating systems.
Any other purpose is considered improper use. Any resulting damage is
excluded from the manufacturer's warranty.
The commercial and industrial use of the appliance for generating
process heat is not permitted.
3.2 Overview of boiler types
Table 2 Appliance types
Z Central heating appliance
W DHW heating
B Condensing technology
R Constant temperature control
21 Output and DHW output up to 71,600 BTU/hr (21 kW)
28 Output and DHW output up to 95,500 BTU/hr (28 kW)
35 Output and DHW output up to 119,400 BTU/hr (35 kW)
42 Output and DHW output up to 143,300 BTU/hr (42 kW)
-3 Version
A Fan-supported appliance
23 Natural gas (NG)
3.3 Rating plate
The rating plate is located at the right side of the appliance.
Fig. 3 Data plate location
The rating plate contains the appliance output, model number, approval
data and serial number.
3.4 Appliance description
• Appliance for wall installation, regardless of chimney and room size
• Bosch Room Controller
• Intelligent boiler pump control
• Heatronic boiler control with 2-wire BUS
• Three-speed boiler circulator
• Automatic air vent (ZWB...-3A only)
•Display
• Automatic ignition
• Continuously-controlled output
• Full protection via the Heatronic with flame rod and solenoid valves
• No minimum circulating water flow rate required
• Suitable for radiant floor heating
• Flue adapter for flue gas and combustion air with test ports
• Variable speed fan
• Gas premix burner
•Temperature sensor and temperature control for space heating
• Supply temperature sensor
•Temperature limiter
• Safety relief valve, pressure gauge
• Expansion vessel (ZWB...-3A only)
• Connection possibility for DHW tank temperature sensor (NTC)
(ZBR...-3A only)
• Flue gas temperature limiter
• DHW priority (ZWB...-3A only)
• Motorized 3-way valve (ZWB...-3A only)
• Hydraulics connection plate
3.5 Accessories
Refer to the Bosch Product Catalog for a complete overview of all
available accessories.
ZBR21-3 A23
ZBR28-3 A 23
ZBR35-3 A23
ZBR42-3 A 23
ZWB28-3 A23
ZWB35-3 A 23
ZWB42-3 A23
6 720 641 933-84.2O