Vitocell 100-H And 300-H Up To 200 Litre Capacity - Viessmann Vitocell 100-H Technical Manual

Installation — DHW cylinders
Fittings that are installed in the connection line must conform to
DIN 1988 (see diagrams on page 29) and DIN 4753 [or local regu-
lations].
These fittings comprise the following:
■ Shut-off valves
■ Drain valve
■ Pressure reducer (to DIN 1988)
Install this device if the pressure in the pipework at the connection
point exceeds 80 % of the safety valve response pressure.
It is advisable to install the pressure reducer immediately down-
stream of the water meter. This creates nearly the same pressures
in the entire DHW system, which is thereby protected against over-
pressure and water hammer.
According to DIN 4109, the static pressure of the water supply sys-
tem after distribution over the various floors upstream of the fittings
should not be higher than 5 bar (0.5 MPa).
■ Safety valve
The system must be equipped with a type-tested diaphragm safety
valve as protection against overpressure.
Permiss. operating pressure: 10 bar (1 MPa)
The connection diameter of the safety valve must be as follows:
– up to 200 l capacity
min. R ½ (DN 15),
max. heat input 75 kW,
– between 200 and 1000 l capacity
min. R ¾ (DN 20),
max. heat input 150 kW,
– between 1000 and 5000 l capacity
min. R 1 (DN 25),
max. heat input 250 kW.
Install the safety valve in the cold water pipe. It must not be able to
be isolated from the DHW cylinder (or the cylinder bank). There must
be no restrictions in the pipework between the safety valve and the
DHW cylinder. Never seal off the safety valve discharge pipe. Ensure
that any expelled water is safely and visibly drained into a sewer.
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 off."
Install the safety valve above the top edge of the DHW cylinder.

Vitocell 100-H and 300-H up to 200 litre capacity

B
A
C
D
DHW connection to DIN 1988
A DHW
B DHW circulation pipe
C DHW circulation pump
DHW heating
(cont.)
F
G H KLM
E
S
M
■ Non-return valve
This prevents system water and heated water from flowing back into
the cold water pipe or into the mains water supply.
■ Pressure gauge
Provide a connection for a pressure gauge.
■ Flow regulating valve
We recommend that a flow regulating valve is installed and the max-
imum water flow rate is adjusted in accordance with the 10-minute
peak output of the DHW cylinder.
■ Drinking water filter
Install a drinking water filter in accordance with DIN 1988. The instal-
lation of a drinking water filter prevents dirt from being introduced
into the drinking water system.
N
G O P
G M
D Spring-loaded check valve
E Visible discharge pipe outlet point
F Safety valve
G
R N
VIESMANN
6
29