Connections on the DHW side
Permissible temperature:
Permissible operating pressure:
Test pressure:
A
D
F
E
U
C
Fig. 18
Expansion vessel
A
Drain outlet
B
DHW circulation pipe
C
DHW
D
Spring-loaded check valve
E
DHW circulation pump
F
Visible discharge pipe outlet point (tundish)
G
Safety valve
H
Shut-off valve
K
Safety valve
The system must be equipped with a type-tested dia-
phragm safety valve as protection against overpres-
sure.
Permissible operating pressure: 10 bar (1 MPa).
The safety valve must have the following connection
diameter:
R
(DN 20), max. heat input 150 kW.
¾
If the heat input of the DHW cylinder exceeds 150 kW,
select an appropriately rated safety valve for the heat
input (see E-DIN 1988-200).
Install the safety valve in the cold water line. Ensure
the safety valve cannot be shut off from the DHW cyl-
inder. There must be no constrictions in the pipework
between the safety valve and the DHW cylinder.
18
(cont.)
(1.0 MPa)
(1.6 MPa)
H
K
M
O
G
L
N
K
B
95 °C
10 bar
16 bar
P
K
R
K
P
O
S
T
Flow regulating valve
L
Pressure gauge connection
M
Non-return valve
N
Drain outlet
O
Cold water
P
Drinking water filter
R
Pressure reducer
S
Non-return valve/pipe separator
T
Temperature sensor, high limit safety cut-out (STB)
U
Never seal off the safety valve discharge pipe. Ensure
that any expelled water is safely and visibly drained
into a drainage system. Position a sign close to the
safety valve discharge pipe, or ideally on the safety
valve itself, with the following inscription: "For safety
reasons, water may be discharged from the discharge
pipe during heating. Never seal."
Install the safety valve above the top edge of the DHW
cylinder.