Viessmann VITOCAL 222-S Installation And Service Instructions Manual page 8

Preparing for installation
Requirements for on-site connections
C DHW circulation
D Opening for 230 V cables
E Cold water
F Liquid line
Connection sizes for hydraulic connections
Pos Sym- Meaning
bol
B – DHW
C – DHW circulation
E – Cold water
F Refrigerant lines from/to
the external unit:
■ Liquid line
G ■ Hot gas line
H
Heating water return
K Heating water flow
1. Preparing connections on the heating
water and the DHW side.
Flush the heating system.
8
(cont.)
G Hot gas line
H Heating water flow
K Heating water return
Connections to the internal unit
7 Connection pipe
(supplied pipe bends)
For type AWT-AC 221.A04, a reduction
from 10 to 6 mm is necessary down-
stream of the pipe bend (reducer ⅝ to ⁷⁄₁₆
supplied).
For type AWT-AC 221.A04, a reduction
from 16 to 10 mm is necessary down-
stream of the pipe bend (reducer ⅞ to
¾ supplied).
2. Prepare the electrical connections.
Note
The internal/external unit BUS con-
necting cable can be routed along the
refrigerant line and fixed to it.
Rp ¾
G 1
Rp ¾
UNF
thread
10 mm
16 mm
Cu 28 x 1 mm
Cu 28 x 1 mm
⅝
⅞