Viessmann VITORADIAL 300-T, Installation Instructions Manual, Page: 6 / 48

6
Danger
Opening the connections on the heating water side whilst the boiler is under
pressure can result in injuries.
First depressurise the boiler.
A Boiler return
up to 263 kW: DN 65
for 335 kW:
DN 80
B Female connection for Therm-Con-
trol temperature sensor, R½
C Female connection for maximum
pressure limiter, R ½
*2
D Safety connection (safety valve),
see page 7
F Boiler flow
up to 263 kW: DN 65
for 335 kW:
DN 80
G Female connection for boiler water
temperature sensor
H Drain, R 1¼
Note
For 300 kW without flash trap, a female
connection R ½, 110 mm long, is
required on site for the high limit safety
cut-out in the flow.
*2 For 335 kW, a low water indicator is required via a minimum pressure limiter;
installation via fitting assembly.
Connecting the heating water side
5458 389 GB