Function - Worcester benchmark ZWB 7-25 R 25 HE Design, Installation And Servicing Instructions

1.7

Function

61 317
4
4
3
0
5
2
E
1
max
Fig. 3
Bosch Heatronic control
4
6 Temperature limiter, heat exchanger
Hot water NTC sensor
6.1
Testing point for gas supply pressure
7
8.1 Pressure gauge
Flue gas temperature limiter
9
Manifold
13
15 Safety valve
Central heating pump
18
20 Expansion vessel
26 Charging Valve
27 Automatic vent
29 Mixer unit
29.1 Bi-metallic thermostat for combustion air compensation
30 Burner
32 Flame sensing electrode
33 Igniter electrode
35 Heat exchanger with cooled combustion chamber
36 Temperature sensor in CH flow
43 CH flow
44 Hot water flow
45 Gas inlet
Cold water inlet
46
47 CH return
52 Solenoid valve 1
Solenoid valve 2
52.1
55 Filter
56 Gas valve CE 427
Main valve disc
57
61 Reset button
6 720 611 441 GB (03.11)
26
27
443
20
63
52
355
ECO
6.1
max
ϑ
13 43 44
229 226
29 33
36
6
29.1
52.1
69
64
56
57
7
55
66.1
90
91 97
45 46
Adjustable gas flow restrictor
63
64 Adjusting screw for min. gas inlet flow volume
Control valve
69
Motor
84
88 3-way valve
Venturi
90
Pressure relief valve
91
93 Water flow regulator
Diaphragm
94
95 Pushrod with switch cam
96 Microswitch
97 Valve for hot water flow volume
98 Water valve
221 Flue duct
226 Fan
229 Inner casing
317 Display
355 Plate-type heat exchanger
358 Condensate trap
422 Digital timer
423 Siphon
443 Diaphragm
Details of the appliance
30
ϑ
88
96
95
94
M
93
98
84
47
6 720 610 599-08.2O
32
221
35
9
358
18
8.1
15
423
7