Bosch Zwb283 Manual

							Operation | 21
6 720 806 993 (2013/03)Greenstar
Frost protection of the DHW tank:
▶ Turn the DHW thermostat   counterclockwise to min (59 °F (15 °C)).
Fig. 11  
4.9 Activating the key pad lock
The key pad lock affects the supply temperature dial, the DHW thermostat, the 
service button and the ECO button.
Activating the key pad lock:
▶ Press the key pad lock button until   and the heating supply temperature are 
alternating on the display.
Fig. 12  
Unlocking the key pad:
▶ Press the key pad lock button until the display shows only the supply 
temperature.
max 123
e
6max 1234
5
6
eco reset
min6 720 641 933-69.1O
max 1234
5
6max 1234
e6
eco reset
6 720 641 933-83.1O
min 
						

							22 | Thermal disinfection
6 720 806 993 (2013/03) Greenstar
4.10 Display codes
5 Thermal disinfection
When using ZBR..-3A appliances with DHW tank it may be necessary to disinfect the 
DHW tank and DHW system after longer idle periods to prevent bacterial 
contamination, for example from legionella bacteria. This step is typically not 
necessary if the drinking water is chlorinated or ozonated.
DisplayDescription
Fault-Code ( chapter 7)
Inspection due
Pump anti-seize function active
Key pad lock active 
Condensate trap filling function active
Bleeding function active
Excessively rapid increase in supply temperature (temp. gradient 
monitoring). 
Heating mode is disabled for two minutes.
If this message appears repeatedly, inform a trained and certified 
heating contractor.
Drying function. If the slab drying function is activated on the 
outdoor reset control unit, refer to the operating instructions for the 
heating control unit included in the scope of delivery.
Table 6   
						

							Thermal disinfection | 23
6 720 806 993 (2013/03)Greenstar
Thermal disinfection covers the DHW system including the taps. For solar DHW 
tanks, the solar portion of the tank is not covered. 
Performing a manual  disinfection of the DHW tank and system
▶ Close all DHW taps. 
▶ Advise occupants of the risk of scalding if no tempering valve is installed. 
▶ Set the time and DHW temperature accordingly on the heating control unit with 
DHW program.
▶ Set any DHW recirculation pump to continuous operation. 
▶ Turn DHW thermostat clockwise to max (approx. 158 °F (70 °C)). 
Fig. 13  
Thermal disinfection can also be carried out automatically and on a 
regular basis; see operating instructions for the heating control unit 
included in the scope of delivery.
DANGER: Risk of scalding! 
Hot water can result in severe scalding.
▶ Carry out thermal disinfection only outside the normal hours of use. 
▶ The water in the tank will take a while to cool down to the set DHW 
temperature as a result of heat loss. Be aware that, after thermal 
disinfection, the DHW may be hotter than the set temperature.
▶ If the thermal disinfection feature is activated have a DHW 
tempering valve installed.
6 720 614 156-16.1O
max1234
5
6
reset
eco
max1234e6 
						

							24 | Energy saving tips
6 720 806 993 (2013/03) Greenstar
▶ Wait until the maximum temperature has been reached. 
▶ Open all DHW taps, from the nearest to the one furthest away, and draw off DHW 
until water at a minimum of 158 °F (70 °C) has flown from all taps for at least 3 
minutes.
▶ Reset the DHW thermostat, DHW recirculation pump, and heating control unit to 
standard operation. 
6 Energy saving tips
Heating economically
The boiler is designed to provide a high level of comfort while keeping gas 
consumption and the resulting environmental impact as low as possible. The gas 
supply to the burner is controlled according to the heat demand. The boiler 
continues to operate on low fire if the demand for heat drops. The technical term for 
this process is modulating control, and it reduces temperature fluctuations and 
provides even distribution of heat throughout the home. This means that the boiler 
may stay on for relatively long periods but will use less gas than an appliance that 
continually cycles on and off.
Inspection/Maintenance
To ensure that gas consumption and environmental impact (pollution, etc.) remain 
as low as possible over an extended period of time, we recommend that you sign an 
inspection/maintenance contract with a trained and certified heating contractor 
covering scheduled annual service and maintenance.
To cancel the thermal disinfection:
▶ Switch the appliance OFF and ON again.
The appliance starts up again and the current supply temperature 
is displayed. 
						

							Energy saving tips | 25
6 720 806 993 (2013/03)Greenstar
Heating control unit
Use a heating control unit with room temperature influence or an outdoor reset 
control unit and thermostatic valves.
For further information, see the operating instructions for the heating control unit 
included in the scope of delivery.
Thermostatic valves
Fully open the thermostatic valves to ensure that the desired room temperature is 
reached in all cases. Allow several days for the system to stabilize after every 
adjustment and only change the setting for the heating curve or the room 
temperature on the control unit after the system had stabilized on the previous 
settings.
Radiant floor heating
Do not set the supply temperature higher than the maximum level recommended by 
the manufacturer.
Room venting
Do not keep windows cracked for ventilation purposes as it continuously cools down 
the room without significantly improving the air quality in the room. It is better to vent 
fully for a short time (with completely open windows).
Turn off the thermostats (if installed) in the room when venting.
Domestic hot water (DHW)
Always set the DHW temperature as low as possible.
A lower setting on the thermostat means a higher rate of energy savings.
Furthermore, higher DHW temperatures result in increased limescale deposits and 
thereby may impair the function of the appliance (e.g. longer heating-up times or 
lower output).
Recirculation pump
If there is a DHW recirculation pump installed, use a timer program to control its 
operation according to the specific requirements (e.g. morning, afternoon, 
evening). 
						

							26 | Troubleshooting
6 720 806 993 (2013/03) Greenstar
7 Troubleshooting
The Heatronic boiler control monitors all safety and control components. 
If a fault arises during operation, an audible warning tone sounds.
The display indicates a fault code (e.g.  ) and the reset button may also be 
flashing.
If the reset button is flashing:
▶ Press the reset button and hold it until   appears on the display.
The appliance starts up again and the current supply temperature is displayed.
If the reset button is not flashing:
▶ Switch the appliance OFF and ON again.
The appliance starts up again and the current supply temperature is displayed.
If the fault persists:
▶ Contact a trained and certified heating contractor for assistance, providing 
details of the fault code and the appliance type and serial number.
Press a button to mute the warning sound.
An overview of the display codes can be found on page 22. 
						

							Maintenance | 27
6 720 806 993 (2013/03)Greenstar
Appliance details
If you need to call a trained and certified heating contractor, you may be asked for  
details on your appliance.
Those details can be found on the rating plate.
Greenstar (e. g. ZBR 28-3 A ...):
........................................................................................................
Serial number:
........................................................................................................
Date commissioned:
........................................................................................................
System installed by: 
........................................................................................................
8 Maintenance
Inspection and maintenance
The operator is responsible for the safety and environmental compatibility of the 
heating system (see local regulations).
It is therefore recommended to sign a maintenance and inspection contract with a 
trained and certified heating contractor that provides annual inspection and 
maintenance. This ensures high efficiency and environmentally compatible 
combustion.
Cleaning the outside of the boiler and the control unit
Wipe down with a damp cloth. Do not use any abrasive or corrosive cleaning agents. 
						

							28 | Environmental responsibility/disposal
6 720 806 993 (2013/03) Greenstar
9 Environmental responsibility/disposal
Environmental responsibility is one of the fundamental company policies of the 
Bosch Group. 
We regard quality of performance, economy and environmental responsibility as 
equal objectives. Environmental protection laws and regulations are strictly adhered 
to.
To protect the environment, we use the best possible technology and materials 
taking into account economic points of view.
Packaging
For packaging, we participate in the country-specific recycling systems, which 
guarantee optimal recycling. 
All packaging materials used are environmentally-friendly and recyclable.
Old appliances
Old appliances contain materials that should be recycled.
The components are easy to separate and the plastics are marked. This allows the 
various components to be sorted for appropriate recycling or disposal. 
						

							Quick reference | 29
6 720 806 993 (2013/03)Greenstar
10 Quick reference
Startup
Turning space heating ON
Heating control
Set outdoor reset heating control unit to 
the relevant heating curve and operating 
mode or set room thermostat to the 
desired temperature.
Key pad lockDHW temperature
ECO button lit – Economy mode.
ECO button not lit – Comfort mode.
Frost protection
m
ax1234
5
66 720 613 896-05.1O
eco reset
6 720 641 933-53.1Omax 1
234
5
6
max 1234
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max 1234
5
6max 1234
e6
eco reset
6 720 641 933-83.1O
min
DANGER: Danger of 
scalding!
▶ In normal operation, 
it is recommended to 
limit the DHW 
temperature to 
122 °F (50 °C) to limit 
the risk of scalding.
6 720 641 933-55.1O
max 1234
5
6
reset
eco
max 1
234e6
eco reset
max 123
5
6max 1234
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6 720 641 933-68.1Omin 
						

							30 | Index
6 720 806 993 (2013/03) Greenstar
Index
C
Certifications .............................................................................................. 7
Cleaning the outer casing ........................................................................... 27
Commissioning ........................................................................................... 8
D
Details about the appliance
  - proper use ............................................................................................ 7
  - type overview........................................................................................ 8
DHW temperature ................................................................................16, 18
Disinfection .............................................................................................. 22
Disposal................................................................................................... 28
E
ECO button ........................................................................................ 18–19
Energy saving tips ..................................................................................... 24
Environmental responsibility....................................................................... 28
F
Fault codes............................................................................................... 26
Faults ...................................................................................................... 26
Frost protection ........................................................................................ 20
G
General information..................................................................................... 5
H
Heating control ......................................................................................... 16
I
Information about the appliance .................................................................... 7