11
H
G
A C
D
F
E
H
B
Fig. 9
350 to 560 kW
A
Boiler return
For 350 kW:
DN 80
For 440 and 560 kW: DN 100
B
Female connection for Therm-Control temperature
sensor (NTC 10 k
Ω
), R
½
C
Female connection for fitting assembly, R
½
D
Safety connection (safety valve)
E
Female connection for high limit safety cut-out
(instead of flash trap), R
½
F
Boiler flow
For 350 kW:
DN 80
For 440 and 560 kW: DN 100
G
Female connection for boiler water temperature
sensor, high limit safety cut-out and temperature
controller
H
Drain, R 1
¼
Making the safety connection and testing for tightness
Safety equipment block installation instructions
Install the safety lines.
Safety connection
■
90 to 350 kW
R 1
¼
■
440 and 560 kW
R 1
½
Permiss. operating pres-
sure:
4 bar (0.4 MPa)
Test pressure:
5.2 bar (0.52 MPa)
Low water indicator
The boiler control unit included as standard prevents
impermissible heating in the case of water shortage.
According to EN 12828, a low water indicator can
therefore be omitted for Vitoplex 300 boilers up to 300
kW (except in attic heating centres).
Therm-Control start-up control (with temperature
sensor NTC 10 k
Ω
)
A shunt pump for raising the return temperature is not
required.
During the start-up phase, ensure that the heating cir-
cuit flow rate is reduced to no more than 50 % by
means of the heating circuit control unit or heating cir-
cuit pumps. This applies during commissioning as well
as after night or weekend shutdowns. For multi boiler
systems, reduce to no more than 50 % of the smallest
boiler.
The heating circuit control unit or the heating circuit
pumps are regulated by means of the factory-fitted
Therm-Control temperature sensor (NTC 10 k
Ω
). For
further details regarding the Therm-Control start-up
system, see the technical guide.
For installation, see separate installation instructions.
Note
Equip the boilers with a safety valve that is type-tested
according to EN 4126. The valve must be marked in
accordance with the system version.
Install all pipe connections free of load and torque
stress.
Connections on the heating water side
(cont.)
5457357
