Ferroli optima 2001 VMF7 Installation Instructions Manual page 11

NOTE: A bypass must be fitted as far as possible from the boiler if thermostatic radiator valves are fitted throughout.
A temporary filling loop of the above type conforming to WRC
approval should be installed between the cold water mains and the
central heating system.
Key
1. Filling point C.H.
2. Temporary connection
3. Cold water supply
Gas
Cold water
TEMPORARY FILLING LOOP
2001
Additional expansion vessel C.H.
Filling
point C.H.
Fig. 6
Fig. 7
(if required)
Bypass
11