Viessmann VITODENS 242-F Technical Manual page 37

Installation accessories
Residual head of the integral circulation pump for the heating circuit with mixer
600 60
500 50
400 40
300 30
200 20
100 10
0 0
0 100 200
Flow rate in l/h
Calculating the transferable heating output (examples)
The maximum heating output that can be transferred via the plate
heat exchanger of the assembly kit is 14 kW. For balanced flow rates
between the regulated heating circuit (assembly kit) and the unregu-
lated heating circuit (radiator heating circuit), the pressure drop in
the assembly kit must be increased.
For this, the line regulating valve with flow indicator available as an
accessory can be fitted to the primary side of the plate heat
exchanger, i.e. between the flow and return. The nominal circulation
water volume of the boiler (see specification), minus the flow rate
through the plate heat exchanger of the assembly kit, results in the
flow rate of the unregulated heating circuit.
Example:
Vitodens 242-F, 5.2-26 kW
■ Nominal amount of circulation water at ΔT 20 K: 1018 l/h
■ Heating output for regulated heating circuit (assumed): 13 kW
■ Resulting flow rate, primary side, plate heat exchanger at ΔT 20 K:
560 l/h ≙ 9.3 l/min (to be set via the line regulating valve)
■ Flow rate of the unregulated heating circuit: 1018 l/h – 560 l/h =
458 l/h
Connection set for DHW circulation pump
Part no. 7514916
For installation in the Vitodens
Comprising:
■ High efficiency circulation pump
■ Flow regulating valve
■ Pipe assembly with thermal insulation
Connection R ½ (male thread)
For installation in the DHW circulation pipe, see page 64.
Note
An additional AM1 or EA1 extension is required for connection to the
Vitotronic.
If required, scalding protection must be installed on site. Automatic
thermostatic mixing valves, part no. 7438 940 and ZK01 815, cannot
be used.
VITODENS
(cont.)
Min.
300 400 500 600 700 800 900 1000 1100 1200
DHW circulation connection set
Part no. ZK03115
For installation in the Vitodens
For installation with on-site DHW circulation pump
Comprising:
■ Flow regulating valve
■ Pipe assembly without thermal insulation
Connection R ½ (male thread)
For installation in the DHW circulation pipe, see page 64.
Note
If required, scalding protection must be installed on site. Automatic
thermostatic mixing valves, part no. 7438 940 and ZK01 815, cannot
be used.
If used, maintain a wall clearance of 140 mm.
Safety assembly to DIN 1988
DN 15
Comprising:
■ Shut-off valve
■ Non-return valve and test connector
■ Pressure gauge
■ Diaphragm safety valve
Max.
1300 1400
VIESMANN
4
37