Bosch Greenstar ZBR 21-3A Installation And Service Instructions For Contractors

Residential gas condensing boiler

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Installation and Service Instructions for Contractors

Residential Gas Condensing Boiler

Greenstar

ZWB 42-3A

WARNING:

Improper installation, set-up, modification, operation or maintenance

of the heating system can cause personal injury and property damage.

Follow these instructions precisely.

If you require assistance or further information, contact a trained and

certified installer or the gas supply company.

WARNING:

The operating instructions are part of the technical documents that

must be handed over to the owner or operator of the heating system.

Explain to the owner or operator how to use the heating system using

the operating instructions. Make sure that they are familiar with all

required information for the safe and proper operation of the heating

system.

These instructions are available in English and French.

Please keep these instructions for future reference.

0010004900-002

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Summary of Contents for Bosch Greenstar ZBR 21-3A

Page 1 Installation and Service Instructions for Contractors Residential Gas Condensing Boiler Greenstar ZBR 21-3A | ZBR 28-3A | ZBR 35-3A | ZBR 42-3A | ZWB 28-3A | ZWB 35-3A | ZWB 42-3A WARNING: Improper installation, set-up, modification, operation or maintenance of the heating system can cause personal injury and property damage. Follow these instructions precisely.
Page 2 Commonwealth of Massachusetts ....23 Programming the Bosch Room Controller ... 52 After commissioning......52 Examples of Installations .
Page 3 Contents 11 Heatronic boiler control settings ..... . . 55 17 Faults ..........73 11.1 Guideline to service functions .
Page 4 Explanation of symbols and safety instructions General safety instructions ▶ When replacing the blocked vent switch, install the new part in the original location. If you hear gas leaking! ▶ A blocked vent switch tripping more than once indicates a problem ▶...
Page 5 Scope of delivery ZWB...-3A - Residential combi boiler for space Scope of delivery heating and DHW generation ZBR...-3A - Residential boiler for space heating and loading of indirect fired DHW tanks 0010016622-003 Fig. 1 Scope of delivery heating boiler ZBR...-3A Contents of package 1: 0010016623-003 Gas condensing boiler...
Page 6 (ZBR...-3A only) • Flue gas temperature limiter • DHW priority (ZWB...-3A only) • Motorized 3-way valve (ZWB...-3A only) • Hydraulics connection plate Accessories Refer to the Bosch Product Catalog for a complete overview of all available accessories. Greenstar – 6721853955 (2024/05)
Page 7 Product Description Product dimensions and minimum clearances ≥ 4" * ≥ 4" * (102 mm) * (102 mm) * 17-21/64" (440 mm) 3-11/32" (85 mm) ≥ 4" ** (102 mm) ** 9-29/64" (240 mm) 13-57/64" (353 mm) 7-7/8 " (200 mm) 0010004928-001 Fig.
Page 8 Product Description Appliance layout heating boiler ZBR...-3A 0010016624-003 Fig. 5 Appliance layout ZBR...-3A Greenstar – 6721853955 (2024/05)
Page 9 Product Description Key to Fig. 5: Heatronic boiler control ON/OFF switch Burner flame indicator Service button Emissions test button Boiler high limit dial DHW thermostat Key pad lock ECO button [10] Reset button [11] Display [12] Condensate trap [13] Test ports for inlet gas pressure [14] Adjustment screw, minimum gas volume [15] Maximum gas adjuster [16] Flue gas temperature limiter...
Page 10 Product Description Appliance layout ZWB...-3A 0010016625-002 Fig. 6 Appliance layout ZWB...-3A Greenstar – 6721853955 (2024/05)
Page 11 Product Description Key to Fig. 6: Heatronic boiler control ON/OFF switch Burner flame indicator Service button Emissions test button Boiler high limit dial DHW thermostat Key pad lock ECO button [10] Reset button [11] Display [12] Condensate trap [13] Test ports for inlet gas pressure [14] Adjustment screw, minimum gas volume [15] DHW temperature sensor [16] Plate-type heat exchanger...
Page 12 Product Description Electrical wiring ZBR...-3A LS NS 6 720 641 933-23.3O Fig. 7 Electrical wiring diagram ZBR...-3A Greenstar – 6721853955 (2024/05)
Page 13 Product Description Key to Fig. 7: Ignition transformer Boiler high limit dial 120 VAC connection DHW tank primary pump or 3-way valve External heating pump for unmixed heating circuit (secondary circuit) 5 or DHW recirculation pump Fuse T 6.3 A (120 VAC) DHW thermostat External safety high limit or low water cut off (LWCO) BUS connection, e.g.
Page 14 Product Description 3.10 Electrical wiring ZWB...-3A LS NS 6 720 641 933-24.3O Fig. 8 Electrical wiring diagram ZWB...-3A Greenstar – 6721853955 (2024/05)
Page 15 Product Description Key to Fig. 8: Ignition transformer Boiler high limit dial 120 VAC connection External heating pump for unmixed heating circuit (secondary circuit) 4 or DHW recirculation pump Fuse T 6.3 A (120 VAC) DHW thermostat External safety high limit or low water cut off (LWCO) BUS connection, e.g.
Page 16 Product Description 3.11 Technical data ZBR...-3A ZBR 21-3 A... Input/Output Unit LPG (propane) Max. input rate 180/79 °F (82/26 °C) BTU/hr (kW) 79,200 (23.2) 77,500 (22.7) Max. output rate 104/86 °F (40/30 °C) BTU/hr (kW) 74,700 (21.9) 74,700 (21.9) Max. output rate 122/86 °F (50/30 °C) BTU/hr (kW) 74,000 (21.7) 74,000 (21.7)
Page 17 Product Description ZBR 28-3 A... ZBR 35-3 A... Input/Output Unit LPG (propane) LPG (propane) Max. input rate 180/79 °F (82/26 °C) BTU/hr (kW) 100,800 (29.5) 98,600 (28.9) 131,900 (38.6) 129,100 (37.8) Max. output rate 104/86 °F (40/30 °C) BTU/hr (kW) 93,800 (27.5) 93,800 (27.5) 122,800 (36.0)
Page 18 Product Description ZBR 42-3 A... Input/Output at elevation 0 - 2000 feet (0 - 610 m) Unit LPG (propane) Max. input rate 180/79 °F (82/26 °C) BTU/hr (kW) 151,600 (44.4) 148,300 (43.5) Max. output rate 104/86 °F (40/30 °C) BTU/hr (kW) 137,500 (40.3) 137,500 (40.3) Max.
Page 19 Product Description 3.12 Technical data ZWB...-3A ZWB 28-3 A... ZWB 35-3 A... Input/Output Unit LPG (propane) LPG (propane) Max. input rate 180/79 °F (82/26 °C) BTU/hr (kW) 100,800 (29.5) 98,600 (28.9) 131,900 (38.6) 129,100 (37.8) Max. output rate 104/86 °F (40/30 °C) BTU/hr (kW) 93,800 (27.5) 93,800 (27.5)
Page 20 Product Description ZWB 42-3 A... Input/Output at elevation 0 - 2000 feet (0 - 610 m) Unit LPG (propane) Max. input rate 180/79 °F (82/26 °C) BTU/hr (kW) 151,600 (44.4) 148,300 (43.5) Max. output rate 104/86 °F (40/30 °C) BTU/hr (kW) 137,500 (40.3) 137,500 (40.3) Max.
Page 21 Product Description ZWB 42-3 A... Input/Output at elevation 0 - 2000 feet (0 - 610 m) Unit LPG (propane) Sound pressure level dB(A) ≤ 45 ≤ 45 Max. supply temperature °F ( °C) 187 (86) 187 (86) Max. permissible operating pressure (P ) heating psi (bar) 30 (2.07)
Page 22 Regulations Regulations Observe all rules, regulations, standards and guidelines applicable to the installation and operation of this appliance in your country. Valves external to the boiler must be fitted with T-handles and condensate piping must be installed in accordance with the State Plumbing Code.
Page 23 Regulations Additional regulations for installations in the • Detailed instructions for the installation of the venting system or the Commonwealth of Massachusetts venting system components; and • a comprehensive parts list for the design and the components of the (a) For all side wall side horizontally vented gas fueled equipment venting system.
Page 24 Motorized valve heating zone 2 To heating zone 2 Bosch room temperature controller heating zone 2 (CRC100) For all accessories not included in the package please refer to the Bosch Motorized valve heating zone 1 Product Catalog. To heating zone 1...
Page 25 PCB in heating boiler ZBR...-3A White plug for mains power supply, 120 V AC, 60 Hz ( chapter 7.3.4, page 47) For all accessories not included in the package please refer to the Bosch 120 V AC, 60 Hz Product Catalog.
Page 26 Fig. 11 Piping Pump heating zone 3 To heating zone 3 Bosch room temperature controller heating zone 3 (CRC100) For all accessories not included in the package please refer to the Bosch Pump heating zone 2 Product Catalog. To heating zone 2...
Page 27 PCB in heating boiler ZBR...-3A White plug for mains power supply, 120 V AC, 60 Hz ( chapter 7.3.4, page 47) For all accessories not included in the package please refer to the Bosch 120 V AC, 60 Hz Product Catalog.
Page 28 NOTICE ▶ Empty out sediment traps. Insufficient antifreeze can accelerate corrosion. ▶ Systems containing antifreeze not approved by Bosch, must be ▶ Follow manufacturer's instructions on antifreeze concentration. completely flushed to ensure no old fluid remains. ▶ Frost protection level has to be checked annually during the regular ▶...
Page 29 Notes on installation and operation The following anti-freeze fluids and concentrations have been approved: 6.1.2 Other important information • The installation of this boiler must comply with all national and local Chemical Name Concentration code and regulations. Nalco (Varidos) FSK 22 - 55 % •...
Page 30 Notes on installation and operation Comparing the size of the integrated expansion Selecting an external expansion vessel (ZBR...-3A) vessel ▶ Determine the size of the expansion vessel in compliance with local laws and regulations. The following diagrams allow verifying that the integrated expansion vessel has sufficient capacity for the intended application, or if an additional expansion vessel is needed (not for radiant floor heating).
Page 31 Notes on installation and operation Pre-installing pipes ▶ Secure the hydraulics connection plate and the mounting bracket with the mounting kits supplied. ▶ Secure the installation template (supplied with the technical documentation) to the wall; observe the minimum side clearances of 4 inches (102 mm) (...
Page 32 Notes on installation and operation Mounting the appliance 5 1/8" NOTICE (130 mm) Residue, metal shavings, and contaminants in the piping can damage the appliance. ▶ Flush the piping thoroughly and completely to remove all residue. ▶ Follow the instructions with respect to water quality ( Chapter 6.1.1, page 28).
Page 33 • Hydrolevel Safgard 1100 Ø > Ø The device is available at most Bosch wholesalers. It requires an external 24VAC AC 20VA transformer provided on site. Ø When a different LWCO is used, it must be installed outside the wall- mounted gas condensing boiler.
Page 34 • Twin pipe PP 2" (50 mm )/ 3" (80 mm) (M&G Duravent PolyPro and Centrotherm InnoFlue) • Concentric PP 3" / 5" (80/125 mm) (Bosch) In case of using the twin pipe adaptor: The twin pipe adaptor is supplied with the boiler kit as standard and is certified as a part of the vent system.
Page 35 Notes on installation and operation ▶ Install the concentric vent adaptor with the screws enclosed. Observe the listed maximum lengths of vent system, which are boiler model dependent ( chapter 6.8.3). DANGER Improper venting of the Greenstar boiler can result in excessive levels of carbon monoxide which can result in severe personal injury or death.
Page 36 M&G Duravent Approved Polypropylene PolyPro and Centrotherm InnoFlue PP rigid venting 3"/5" (80/125 mm) ANSI Cat IV concentric (Bosch, Approved Polypropylene manufactured by M&G Duravent) PP-Flex 3" (80 mm) vent or air ANSI Cat IV BH Gas venting systems, pipe M&G Duravent...
Page 37 Ø 3" (Ø 76 mm) twin pipe termination M&G Duravent PolyPro 3PPS-HTP Ø 3" (Ø 76 mm) single pipe termination M&G Duravent PolyPro 3PPS-HST Ø 3"/5" (Ø 80/125 mm) Bosch Greenstar Horizontal Bosch (manufactured by 7738003218 Telescopic Terminal Kit M&G Duravent) Table 16 Wall terminals...
Page 38 Notes on installation and operation 6 720 641 933-17.1O Fig. 31 Vent and combustion air pipe position Forced Air Inlet Gravity Air Inlet Exhaust terminal 1 foot (305 mm) Clearance in accordance with local installation codes and the requirements 1 foot (305 mm) 3 feet (915 mm) in Canada for models ZBR 35-3 A and ZBR 42-3 A Clearance in accordance with local installation codes and the...
Page 39 Notes on installation and operation 6.8.2 Examples of approved horizontal and vertical venting ≥ 4" installation (102 mm) NOTICE ▶ Place pipe supports every 5 ft (1525 mm) of horizontal and vertical run, beginning with support near wall-mounted gas condensing boiler.
Page 40 Notes on installation and operation 6 720 641 933-09.2O Fig. 36 Vertical venting system (sealed combustion) 6 720 641 933-10.1O 6 720 641 933-07.1O Fig. 37 Vertical venting system (room air only) Fig. 38 Vertical venting system (sealed combustion) Key to Fig. 36, Fig. 37 and Fig. 38: Intake Exhaust Greater than 12 inches (305 mm)
Page 41 Notes on installation and operation 1/4" per foot (50 mm per meter) 6 720 641 933-78.1O Fig. 41 Horizontal venting system (telescopic concentric vent kit) 6.8.3 Vent and combustion air pipe lengths With Flex Pipe the maximum length is reduced by 50%. Flex Pipe according to the suppliers instructions for use in the vertical part of the installation only.
Page 42 Notes on installation and operation Installations  Fig. 35 Stainless steel wall termination Fitting Equivalent 2" PIPE Maximum straight vent pipe length allowed for Ø 2" pipe 45° elbow 0.91 Number of 90° elbows ZBR 21-3A ZBR 35-3A 90° elbow 1.82 used ZBR 28-3A...
Page 43 7.2.2 Connecting the BUS-system the installation instructions of the accessory. Connect only Bosch room controls to the internal BUS of this boiler. For further details see the technical documentation of the BUS system components (e. g. CRC200 and CZM100). Greenstar – 6721853955 (2024/05)
Page 44 ▶ Secure the cable with the strain relief. 6 720 811 153-05.1O Fig. 45 Schematic of electrical wiring of Bosch room control and boiler Terminal at the boiler reads BUS or BB, both indicating connection of the 2-wired Bosch BUS system.
Page 45 Electrical connection 7.2.5 Connecting additional accessories ▶ For splash protection (IP), always cut the strain relief to match the diameter of the cable. ϑ 6 720 641 933-91.1o ≤ 4" Fig. 48 Cut off grommets (102 mm) ▶ Feed cable through strain relief and connect accordingly. 6 720 641 933-97.1o ▶...
Page 46 -or- ▶ Use service function 5.E to set connection to 03 (external heating 6 720 641 933-42.3O pump). Fig. 53 Mounting rails for junction box The DHW recirculation pump is controlled by the Bosch Room Controller. Greenstar – 6721853955 (2024/05)
Page 47 Electrical connection 7.3.3 DHW tank loading pump or 3-way valve with spring return ▶ Connect cable to the white plug according to Fig. 58. (only ZBR...-3A) The pump used must have the following connection values: 120 VAC, max. 2 A. ▶...
Page 48 Electrical connection Connecting the LWCO device ▶ Connect the leads labeled SWITCH CONTACT (yellow) to the TB1 temperature switch ( Fig. 49, page 45) on the Heatronic. NOTICE System damage or malfunction! ▶ Ensure the air box remains air-tight when routing the LWCO cable to the outside.
Page 49 Commissioning Commissioning eco reset 6 720 641 933-25.1O Fig. 62 Overview of the controls Emissions test button Service button Burner operation indicator lamp ON/OFF power switch Key pad lock ECO button Reset button Display Automatic air vent (ZWB...-3A combi boilers only) [10] Boiler water pressure gauge [11] DHW thermostat [12] Safety relief valve discharge hose...
Page 50 Commissioning Before operating the appliance Heat setting 8.3.1 Switching on the heating NOTICE Set the maximum supply temperature based on the structure's heat loss Commissioning without being properly filled and purged will on design day. damage the appliance. ▶ Only operate this appliance after ensuring there is sufficient water in Boiler high Typical supply Sample application...
Page 51 Commissioning ▶ Select P0 and set the summer shut down temperature to activate outdoor reset. Standard setting is 32 °F (0 °C) which is outdoor reset turned off. P0 can be set between 33 - 86 °F (1 - 30 °C) outdoor temperature.
Page 52 Setting the DHW temperature ▶ Set the DHW temperature on the DHW thermostat Observe the operating instructions for the Bosch room controller The set DHW temperature flashes on the display for 30 seconds. included in the scope of delivery. There you can read: ▶...
Page 53 -or- may run even if no DHW is being drawn. ▶ If you want to leave the appliance switched OFF: Mix Bosch- • Economy mode, ECO button lights up approved anti-freeze into the heating water ( Tab. 28, page) and –...
Page 54 ZBR...-3A appliances (heating boiler) with DHW tank: Thermal disinfection Boiler circulator reset 10.1 Pump anti-seize protection This function prevents the heating zone pump from seizing up following longer idle periods. 6 720 615 065-17.1O The appliance will briefly run the pump at least every 24 hours after its Fig.
Page 55 Heatronic boiler control settings Heatronic boiler control settings 11.1 Guideline to service functions The Heatronic allows easy setting and testing of many appliance functions. For an overview of service functions, see Chapter 11.2 on page 56. reset V / gpm 6 720 641 933-52.1O Fig.
Page 56 Heatronic boiler control settings 11.2 Overview of the service functions 11.2.2 Heating curve 11.2.1 First service level (press and hold the service button until it lights up) Service function Display Page Maximum space heating output Maximum DHW output Pump mode for space heating operation Pump mode Heating circuit pump lockout time Maximum supply temperature...
Page 57 Heatronic boiler control settings 11.3 Description of the service functions Service function 1. F: Pump mode (only heating boiler ZBR...-3A) 11.3.1 First service level NOTICE System damage or boiler malfunction! Service function 1.A: Maximum space heating output Some gas supply companies offer a performance-dependent basic ▶...
Page 58 Heatronic boiler control settings The following settings are available: • 00: Automatic adaptation of the anti-cycle time is disabled This service function allows activating the purging function manually, • 01: Automatic adaptation of the anti-cycle time is enabled e.g. after servicing. Default setting is 00 (switched off).
Page 59 The appliance can be set to sound an audible alarm to alert the operator deactivated). of a fault present. The audible warning tone can be deactivated with the • 01: DHW recirculation pump enabled - See Bosch room controller service function 4.d. instructions on how to set a recirculation pump program.
Page 60 Heatronic boiler control settings Service function 6.C: Supply temperature required by outdoor reset The following settings are available: control • 00: Off This service function allows displaying the current target supply • 01: Heating operation only in accordance with the appliance or temperature set by the outdoor reset control.
Page 61 Default setting is 50. Service function 9.E: Turbine signal delay (only combi boiler ZWB...- Service function 8.C: GFA Gas burner control unit status Internal parameter. If you are on the line with Bosch Technical Support you may be asked for this number. NOTICE Service function 8.d: GFA Gas burner control unit fault...
Page 62 Gas adjustment 12.2 Installation location higher than 2,000 feet Gas adjustment (610 m) above sea level Input and output rates are reduced at higher altitudes due to thin air with DANGER reduced oxygen levels. Personal injury and property damage ZBR 42-3A... and ZWB 42-3A... appliances are derated at 3% per ▶...
Page 63 Gas adjustment ▶ Measure the CO or O level and the CO content of the flue gas ▶ Remove screw ( Fig. 83, [3]) from the gas valve adjustment screw ( Section 13). ( Fig. 83, [2]) and set CO or O value for minimum nominal output.
Page 64 Flue gas test 12.4 Dynamic gas pressure test port Flue gas test ▶ Switch the appliance OFF and close the gas shut-off valve. ▶ Loosen the screw in the test port for gas inlet pressure ( Fig. 52, 13.1 Emissions test button [1]) and connect a pressure gauge (...
Page 65 ▶ Cleaning of the heat exchanger should not be necessary until five years after the initial commissioning. ▶ Only use a Bosch cleaning blade and Bosch cleaning brush. ▶ Only clean heat exchanger when visibly dirty. Greenstar – 6721853955 (2024/05)
Page 66 Inspection and maintenance 15.1 Description of various steps 15.1.3 Plate type heat exchanger (only combi boiler ZWB...-3A) 15.1.1 Calling up the latest fault (service function 6.A) If the DHW output on the combi boiler is significantly reduced: ▶ Select service function 6A (page 59). ▶...
Page 67 Inspection and maintenance 15.1.4 Checking electrodes ▶ Remove electrode set including gasket and check electrodes for contamination; clean or replace, if required. ▶ Reinstall electrode set with new gaskets and check for leaks. 2-1/4 + 3/4 ft.-lbf. 3 + 1 Nm 6 720 641 933-48.2O Fig.
Page 68 ▶ Cleaning of the heat exchanger should not be necessary until five gas condensing boiler. years after the initial commissioning. ▶ Only use a Bosch cleaning blade and Bosch cleaning brush. ▶ Remove burner lid (steps 1 - 4). ▶ Only clean heat exchanger when visibly dirty.
Page 69 Inspection and maintenance ▶ With the cleaning blade, clean the heat exchanger block from the ▶ Rinse the heat exchanger with water from the top. bottom to the top. 6 720 612 664-18.1R Fig. 100 Rinsing the heat exchanger ▶ Clean the condensate tray (with reversed brush). 6 720 641 933-71.1O Fig.
Page 70 Inspection and maintenance 15.1.7 Cleaning condensate trap 15.1.9 Checking the expansion vessel ▶ Remove condensate trap (steps 1 and 2) and check heat exchanger Annual inspection of the expansion vessel is required. orifice for clear passage. ▶ Depressurize the appliance. ▶...
Page 71 Inspection and maintenance 15.2 Maintenance and inspection checklist ▶ Use this form to guide you through the service and maintenance procedure. Fill out each step according to the findings and work performed. Date  Latest fault code from service function 6.A. Fresh water inlet filter (Combi boiler ZWB appliances only).
Page 72 Readings on the display Readings on the display Status Description code The 7-segment display shows the following: Acknowledge by pressing any button (except reset). Value displayed Description Range Number or letter, dot Servicefunction followed by letter ( Tab. 26/ 27, page 56/ 56) Acknowledge by pressing two buttons Letter followed by...
Page 73 Faults ▶ Switch the appliance OFF and ON again. Faults The appliance starts up again and the current supply temperature is displayed. 17.1 Troubleshooting DANGER An overview of the faults can be found on page 74. Explosion! An overview of the status codes can be found on page 72. ▶...
Page 74 Faults 17.2 Faults that are shown on the display Display Description Elimination DHW temperature sensor defective. ▶ Check temperature sensor and leads for interruptions or shorts, and replace if defective. ▶ Insert code plug correctly; replace if defective. Communication fault. ▶...
Page 75 Faults Display Description Elimination No flame detected. ▶ Check that ground lead is properly connected, replace if defective. ▶ Check that gas cock is open. ▶ Check inlet gas pressure; correct if needed. ▶ Check power supply. ▶ Check electrodes for visual damage; replace if defective. ▶...
Page 76 Faults 17.3 Faults that are not shown on the display Appliance faults Elimination Combustion noise too loud; rumbling noises ▶ Insert code plug correctly; replace if defective. ▶ Check gas type. ▶ Check inlet gas pressure; adjust if defective. ▶ Check flue gas system; clean or repair if defective. ▶...
Page 77 Faults 17.4 Check sensor values 17.4.1 Outdoor temperature sensor 17.4.3 Supply temperature sensor, External supply temperature sensor, DHW tank temperature sensor, DHW temperature Temperature °F ( °C ) Resistance [ ] sensor Testing tolerance ± 10% Temperature °F ( °C) Resistance [ ...
Page 78 Commissioning log for the appliance Commissioning log for the appliance Home owner/operator: Last name, first name Number, Street Telephone/fax ZIP code, town System installer: Order number: Appliance type: (Complete a separate log for every appliance!) Serial number: Date commissioned:  Individual appliance |  Cascade, Number of appliances: ..Installation location: ...
Page 79 Commissioning log for the appliance  System hydraulics checked, notes: Modified service functions: Select the modified service functions and enter the values here. Heating control:  Outdoor reset control  Room temperature-dependent control  Remote control × ..Qty, heating zone(s) coding: ...
Page 80 50 Wentworth Avenue Londonderry, NH 03053 Tel. 603-552-1100 Fax 603-965-7581 www.bosch-homecomfort.us U.S.A. Products manufactured by Bosch Thermotechnik GmbH Junkersstrasse 20-24 D-73249 Wernau www.bosch-homecomfortgroup.com Bosch Thermotechnology Corp. reserves the right to make changes without notice due to continuing engineering and technological advances.

This manual is also suitable for:

Greenstar zbr 28-3a Greenstar zbr 35-3a Greenstar zbr 42-3a Greenstar zwb 28-3a Greenstar zwb 35-3a Greenstar zwb 42-3a