Datasheet

5822 239
G
B
9
2.3 Safety equipment
Safety equipment selection table
This table indicates the safety equipment required for each system acc. to DIN 4751-2.
(X = required, – = not required)
Rated boiler output
≦ 350 kW > 350 kW
Safety temperature
(STB setting
*1
, STB part of the standard
delivery of the boiler control unit)
and
100 ºC 110 or 120 ºC 100 ºC 110 or 120 ºC
a
n
d
operating pressure
(safety pressure)
≦ 30bar
> 30bar ≦ 30bar > 30bar unlimited
Control thermostat
Standard delivery of the boiler control unit
X X X X X X
Boiler thermometer
Standard delivery of the boiler control unit
X X X X X X
Pressure gauge assembly
Pressure gauge (as separate accessory)
or
as part of the maximum pressure
limiting assembly or the safety
equipment block
X X X X X X
Safety valve
A
3
b
f
t
l
i
t
f
t
h
X X X X X X
A3barsa
f
ety valve is part o
f
the
safety equipment block
on site on site
Water level limiter
A
l
t
i
d
i
t
f
t
i
l
– – – – – X
As low water indicator
f
or vertical
installation into the boiler
Max. pressure limiting assembly
Incl.
p
ressure
g
au
g
e
,
p
rotected shut-o
f
f
– X – X X X
I
n
c
l
.
p
r
e
s
s
u
r
e
g
a
u
g
e
,
p
r
o
t
e
c
t
e
d
s
h
u
t
-
o
f
f
valve, drain and additional connector for
an additional high limit safety cut-out
Min. pressure limiting assembly
W
i
t
h
t
t
d
h
t
f
f
l
d
– – X X – X
With protected shut-o
f
f
valve and
drain
Flash trap
– – – – X
*2
X
p
on site
High limit safety cut-out
*2
(additional)
– – – – X
*2
–
Safety pressure limiter
*2
(
a
d
d
i
t
i
o
n
a
l
)
– – – – X
*2
–
(additional)
(Maximum pressure limiter)
*1
In its delivered state, the high limit safety cut-out (STB) for Vitotronic is set to 120 ºC and should be adjusted for lower safety
temperatures.
*2
According to DIN 4751-2, the flash trap may be omitted, if the high limit safety cut-out of the boiler control unit has been set to
100 ºC and an additional high limit safety cut-out and safety pressure limiter (maximum pressure limiter) are installed.