49
1.5
Main water circuit
3
4
5
14
13
15
16
18
19
10
9
7
11
17
21
20
12
6
M
U
G
E
R
Sc
S
8
2
1
Fig. 4
KEY:
M System delivery
R System return
U Domestic hot water outlet
E Domesti hot water inlet
S Safety valve outlet
G Gas supply
Sc Condensate outlet
1
Condensing heat exchanger
2
Combustion chamber
3
Fan
4
Thermal safety thermostat
5
Delivery sensor
6
Domestic hot water heat exchanger
7
Pressure transducer
8
Pressure gauge
9
Automatic bleed valve
10
Pump
11
System expansion vessel
12
Diverter valve
13
Automatic by-pass
14
Domestic hot water sensor
15
Gas valve
16
Domestic hot water flow meter
17
Domestic hot water filter
18
Boiler drain
19
System relief valve
20
System filling
21
Condensate siphon outlet
