Slant/Fin VHG-100-CH, Installation And Service Manual

Page: 119 / 164

E93.1901EN032 Installation and Service Manual SlantFin VGH-CH / CO
119
14 CASCADING
System setup
For proper functioning of the system, certain settings have to be changed.
See paragraph 14.2
The boiler controller can control multiple boilers in a cascade setup.
A system sensor input is available on the main board to measure the cascade system supply temperature. A
circulator output is also available to run the system circulator, as well as an output for the DHW circulator.
When the CH supply temperature is calculated based on an outdoor sensor, only one outdoor sensor is needed.
This sensor is connected to the managing boiler and calculates the CH setpoint for the cascade system.
A cascade system can be used with an DHW indirect tank. A DHW circulator and sensor can be connected to the
managing boiler.
Cascade boiler pump connections for system configuration as shown in Figure 14.1.
System configuration for handling DHW indirect tank or Central Heating demand.
All boilers handle
either indirect tank or Central Heating demand at one time.
Boiler cascade communication setup
In order for the system to work for cascade the communication busses must be parallel linked together. The
managing boiler uses the AL-bus connection 21-22 for the cascade. The 10-11 connection terminals of the
depending boilers must be connected to 21-22 connection terminals of the managing boiler (see paragraph 10.3.1).
It is important that the power on the 10-11 connection terminals on all dependent boilers is switched to the OFF
position (see also paragraph 14.2.1).
All boilers in the cascade system must have a unique address selected.
Before commissioning a cascade installation, a number of parameters have to be changed.
These parameters can be programmed on the unit itself.
Figure 14.1
10 11 10 11
21 22
10 11
10 11
M
an
ag
in
g
De
pe
nd
in
g
De
pe
nd
in
g
De
pe
nd
in
g
De
pe
nd
in
g
NOTICE