System Layout 3 - Viessmann VITOCROSSAL 300 Technical Data Manual

Installation Examples

System Layout 3

Vitocrossal 300 CU3A with...
- DHW storage tank
- one direct-connected heating circuit
- one heating circuit with a mixing valve
Legend
Vitocrossal 300 CU3A boiler with
A
Vitotronic 200, KW6B outdoor reset
control
Outdoor temperature sensor !
B
C Vitotrol remote (optional)
Under floor heating circuit
D
E Radiator heating circuit
F Heating circuit pump
Mixing valve temperature sensor ?
G
H Accessory kit for heating circuit with mixing valve
Domestic hot water storage tank
I
DHW tank temperature sensor %
J
K Expansion tank
Temperature and pressure relief valve
L
Pressure relief valve
M
N DHW recirculation pump
Boiler pump
O
20
P DHW circulating pump sA
* Function based on coding of address 33
22
*
28/20
Vitocrossal 300 CU3A 26 to 57 Technical Data
Installation of different heating circuits...
radiator heating circuit (high-temp. circuit)
■
under floor heating circuit with 3-way mixing valve
■
(low-temp. circuit)
■ DHW production
The 3-way mixing valve, built-in to achieve the low-
temperature level of the under floor heating circuit, is
controlled by an accessory kit for a heating circuit with
mixing valve.
IMPORTANT
System separation is required of underfloor heating
systems employing non-oxygen diffusion barrier tubing.
All components on the secondary side of the heat
exchanger must be made of corrosion-resistant materials.
IMPORTANT
Sizing of field-supplied pump P is critical for proper boiler
operation in this system layout. See page 8 for the supply
head pressure drop of the boiler. An undersized pump
may cause short-cycling and/or improper operation of the
boiler.