Bosch 12/18 User Manual

Page of 52
LAYOUT & COMPONENTS
The diagram opposite excludes the top, front
and RH side casing panels.
1.   CONTROL BOX ASSEMBLY
2.   DIVERTER VALVE
3.   PRESSURE GAUGE
4.   AUTO AIR VENT
5.   CH CONTROL AND MANUAL RESET
OVERHEAT THERMOSTAT PHIAL
6.   CASING SIDE PANEL
7.    CIRCULATING PUMP
8.   AUTO-RESET HIGH LIMIT 
THERMOSTAT PHIAL
9.   DHW FLOW SWITCH
10. PRESSURE RELIEF VALVE
11. DHW HEAT EXCHANGER
12. FLUE GAS SAMPLING POINT
13. FLUE OVERHEAT THERMOSTAT 
PHIAL
14. CASING SUPPORT PANEL
15. FLUE MANIFOLD ACCESS COVER
16. AIR INLET PIPE AND CASING 
17. SECONDARY HEAT EXCHANGER
BLEED POINT (ONE ON EITHER SIDE)
18. SECONDARY HEAT EXCHANGER
19. SECONDARY HEAT EXCHANGER
DRAIN
20. EXPANSION VESSEL
21. OPTIONAL OPEN VENT/AIR VENT
22. DRAIN AND OPTIONAL FEED AND 
EXPANSION
23. CONDENSATE OUTLET
24. PRIMARY HEAT EXCHANGER
25. TRAY
26. OIL ISOLATION VALVE
27. CONDENSATE TRAP
28. CONDENSATE TRAP BRACKET
29. COMBUSTION CHAMBER ACCESS
DOOR
30. HEATSLAVE TANK DRAIN
31. HEATSLAVE TANK
32. MODE SWITCH
33. BOILER MODE INDICATOR
34. LOCKOUT INDICATOR
35. OVERHEAT RESET BUTTONS (boiler & 
flue temperature)
36. LOCKOUT RESET BUTTON
37. SERVICE CONNECTION
38. CH TEMPERATURE CONTROL
39. DHW TEMPERATURE CONTROL
40. DATA LABEL
41. FROST THERMOSTAT SENSORS
42a. B E NTO N E STE R LI N G B U R N E R
(12/18 & 18/25)
i)   CONTROL BOX
ii)  MOTOR
iii) AIR INTAKE CASING
iv) OIL PUMP
v)  COMBUSTION HEAD
42b. RIELLO RDB 2.2 BURNER (25/32)
i)   CONTROL BOX
ii)  MOTOR
iii)  AIR INTAKE CASING
iv) OIL PUMP
v) COMBUSTION HEAD
43.  CLIP - AIR INTAKE HOSE
44.  AIR INTAKE HOSE
LAYOUT & COMPONENTS
INSTALLATION & SERVICING INSTRUCTIONS FOR WORCESTER GREENSTAR HEATSLAVE EXTERNAL 12/18-18/25-25/32
8 716 113 389b (09/07) 
6
A
PPL
IA
N
C
E
INF
O
RM
A
T
IO
N
1
6
2
4
8
7
5
10
20
11
14
3
13
15
12
16
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19
21
22
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24
25
29
40
30
31
32
33
9
35/36
39
38
42a
42b
43
44
43
44
v)
iv)
iii)
ii)
i)
v)
iii)
i)
ii)
iv)
41
26
27
28
37
34