Selection Of Low Loss Header - Vaillant ecoTEC VU 656/4 Installation And Maintenance Instructions Manual

5 Installation
Selection of the low loss header
The low loss header uncouples the boiler from the
heating system. A sufficiently large water volume is
constantly supplied through the boiler via the low loss
header in conjunction with the boiler pump. It acts as a
neutral point in the system and has minimal hydraulic
resistance, therefore the boiler pump does not affect
the circuit pumps and vice-versa.
A suitable WH type low loss header can be chosen from
Table 5.1.
Temperature difference of heating system
Output of heating 10 K
system
Stand-alone boiler WH 160
Two cascade WH 280
arrangement
Three cascade WH 280
arrangement
Table 5.1 Selection of the low loss header
No electrical accessories are required in order to use a
low loss header. Simple systems can be connected
directly inside the electronic box.
Model Article- Connection
number Sizes
1
WH 95 306721 2" BSP (f)
WH 160 306726 DN65
WH 280 306725 DN80
Table 5.2 Low loss headers dimensions
All dimensions in mm
* = distance between flanges
14
15 K 20 K
WH 95 WH 95
WH 160 WH 95
WH 280 WH 160
Header Header Total
width depth height
A B C
155 155 750
520* 120 1350
600* 160 1390
Insulation To boiler To heating
dimensions circuit
D
155/155 470
220/220 900
260/260 930
Installation and maintenance instructions ecoTEC 0020029173_01
Height from Maximum
floor volume flow
E F
540 n/a
900 300
930 300
3
m /hr
8
12
21.5