Part 7 - Central heating (CH) and Domestic Hot Water (DHW) circuit
Installation examples
The schematics on the following pages are to be seen as guidelines only. They do not display all system
varieties, safety devices or concepts possible. Layouts number 1 and 2 give information on how to
connect the boiler to the CH and/or DHW system. Layouts number 3 till 10 give examples on how to
position the boiler in several system configurations.
Legend
HO
Heating Only appliance
IET
Internal Expansion Tank
OEET
Optional External Expansion Tank
AV
Air Vent (Automatic)
FL
Filling Loop
PRV
Pressure Relief Valve
A
CH supply
B
Not used / capped
B
Mains w ater sup ply fo r filling l oop (Hxxx ) typ es
C
Tank supply hot (Hxxx types)
D
CH and Tank return (Hxxx types)
A B C D
1) Boiler layout :
Heating only appliance
Legend
Combi
Combi appliance
IET
Internal Expansion Tank
OEET
Optional External Expansion Tank
AV
Air Vent (Automatic)
FL
Filling Loop
PRV
Pressure Relief Valve
E
CH supply
F
DHW outlet
G
Cold tap water inlet (Cxxx types)
H
CH return (Cxxx types)
E F G H
2) Boiler Layout:
Combi appliance
43
R Series
R Series