Bosch C 1050 Manual

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Installation instructions31
3.11 Filling the condensate trap
The  condensate  trap  can  be  filled  before  or  after 
connecting the vent pipe. 
Filling  the  condensate  trap  before  vent  pipe 
installation BFill  the  condensate  trap  by  pouring  approx.14  oz. 
(400ml)  of  water  into  the  exhaust  accessory  on  the
top of the appliance, see Fig. 35.
Fig. 35 Filling the condensate trap at start up 
Filling  the  condensate  trap  after  vent  pipe 
installation 
After  appliance...

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Installation instructions
3.12 Domestic hot water recirculation
Although  recirculation  directly  through  the  tankles
s
water  heater  is  allowed,  temperature  stability  is 
improved by recirculating through a mini-tank as sh own
in  Fig.  40.  By  using  the  design  in  Fig.  40,  there  i s  no
recirculation  of  hot  water  through  the  tankless  wat er
heater  and  therefore,  does  not  affect  the  heat
exchanger  warranty.    Direct  recirculation  through  t he
tankless...

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Installation instructions33
3.13 Space heating applications
Bosch  tankless  water  heaters  are  approved  for  use  i n
combination  DHW  and  space  heating  applications 
(open-loop  setup).  These  water  heaters  are  not
approved  for  use  in  space  heating  only  applications
(closed-loop  setup).  Bosch  supports  applications  of
combination  DHW  and  space  heating  in  an open  loop
configuration  if  plumbed  similar  to  Fig.  42.  Use  of   a
Bosch  tankless  water  heater...

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Installation instructions 
Fig. 42 Space heating diagram
1
Hot water outlet
2 Cold water inlet
3 Pressure relief valve
4 Gas supply
5 Shut off gas valve
6 Thermal expansion tank (as required)
7 Atmospheric vacuum breaker
8 Cold inlet
9 Check valve
10 Pump
11 Thermostatic mixing valve
12 Thermometer (optional)
13 DHW outlet
14 Water to water heat exchanger
15 Backflow preventer
16 Automatic water feed
17 Thermostat
18 Space heating zone
19 Zone controller
20 Space heating pump
21 Expansion...

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Installation instructions35
3.14 Measuring gas pressure
Confirm gas pressure upon installation. 
Connecting manometer BShut off gas supply at installer supplied shutoff v alve
for this water heater.
B Remove front cover and locate inlet gas pressure te st
port (see Fig. 44).
B Loosen  screw  inside  left  test  point  fitting  (do  not 
remove) and connect manometer tube to test point.
Static Pressure Test B Turn gas supply back on.
B Record static gas pressure reading in table 22....

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Electrical connections
4 Electrical connections
4.1 Electrical power supply
The  water  heater  requires  an  electrical  power  suppl
y
from  a  120VAC  /  60Hz  properly  rated  receptacle  and 
must be properly grounded.
The  heater  is  wired  as  shown  in  the  wiring  diagram
(chapter 9, Fig. 72). 
Fig. 45 Connecting power supply cord
1 Power cord length: 3ft.
Note: Outlet appliance is plugged in to should be  
clear from possible water damage.
4.2 Position of the fuses in control...

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Operation instructions37
5 Operation instructions
Fig. 48
1On/Off button
2 Reset button
3 Program Key
4 LCD display
5 Up button
6 Down button
7 Power On or stand-by LED
5.1 Description LCD Display
Fig. 49 Power bar indicator (input) 
Fig. 50 Temperature indicator 
Fig. 51 Error indicator Fig. 52 Locked condition indicator (only with remote
 
control)
Fig. 53 Flame indicator 
Fig. 54 Solar mode indicator (see chapter 5.4, page  38)
Fig. 55 Remote control indicator
Warning:  Do not use any...

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Operation instructions
5.2 For your safety read before 
operating your water heater
A. This appliance is equipped with electronic ignitio n for
lighting  the  main  burner.  When  turning  the  heater  o n,
follow these instructions exactly. 
WHAT TO DO IF YOU SMELL GAS B Do not try to light any appliance.
B Do  not  touch  any  electric  switch;  do  not  use  any 
phone in your building.
B Immediately  call  your  gas  supplier  from  a  neighbors
phone. Follow the gas supplier’s...

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Operation instructions39
Solar mode 
The water heater will not ignite if inlet water tem
perature
exceeds  the  set  temperature  on  the  appliance.  In  th is
condition,  the  solar  mode  indicator  will  show  on  th e
LCD display.  See Fig. 54, page 37. 
Fig. 58
5.5 Use of optional remote control 
accessory (part no. TSTAT2)
Fig. 59 Remote control 
The  wireless  remote  control  accessory  (Fig. 84, 
component  13)  and  the  temperature  selector  buttons
on  the  front  of  the...

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Operation instructions
5.8 Program button
Fig. 63 “Program” key 
5.8.1 Memorizing selected temperature B
Press  buttons    or    to  select  desired 
temperature.
B Hold  “Program”  button  for  3  seconds  to  save
temperature.
When LCD stops blinking, temperature is saved in 
memory. 
Using “Program” function 
In order to select memorized temperature B Press “Program” key.
LCD shows pre-memorized temperature, which is now 
the hot water selected temperature.
5.9 Locked condition
This...