Viessmann Vitodens 200 Technical Manual page 42

1.3 Selection guide for DHW heating
Instantaneous water heater
200
Instantaneous water heater (Vitodens 200, gas fired combi boiler)
An electronically regulated plate heat
exchanger is integrated into the
Vitodens 200.
Plate heat exchanger specification
1
Content
Connections
Hot and cold water
Max. operating pressure
Output
Rated output range of the
gas fired combi boiler
Continuous DHW output
for heating DHW
from 10 ºC to 45 ºC and
an average heating water
temperature of 70 ºC
Drawing rate
Outlet temperature,
adjustable
DHW temperature subject to volume flow
65
60
55
50
45
D
40
35
6 6.5 7 7.5
Volume flow at the tap (mixed water volume) in l/min
42
This makes DHW at drawing temperature
instantly available from Vitodens for
approx. 45 s.
litres
G (male thread)
bar
kW
kW
litres/h
litres/minute
ºC
B
8 8.5 9 9.5 10 10.5 11 11.5
A
12 12.5 13 13.5 14
The adjacent diagram illustrates the
changes in outlet temperature, subject to
the volume flow at the tap.
The DHW volume drawn is limited by a
throughput limiter to 8 litres/minute D.
If a greater volume of water is required
cold water needs to be admixed, which
reduces the outlet temperature.
The illustration of the outlet temperature
characteristics is based on a cold water
inlet temperature of 10 ºC.
A DHW outlet temperature at Vitodens
B Mixing range
C DHW outlet temperature at the
mixer tap
D Throughput limitation
VITODENS
0.2
½"
10
8.8 26.0
24
590
3 8
10 57