LAARS NeoTherm LC NTV1700 - Install and Operating Manual - Manual (Page 6)

LAARS Heating Systems Page 2
• Each controller and burner work together. Each
boiler includes two of these controller/burner
combinations.
Notice the different terms we are using here.
The term boiler refers to the whole appliance
– the complete NeoTherm LC 1000 or 1700.
Each boiler includes two separate controller/
burner pairs.
• NeoTherm LC 1000 and 1700 units are always
set up for “Lead/Lag” operation. The term
“Lead/Lag” means that, as the heating load
increases, the control system brings additional
burners on automatically.
Touch
Screen
Boiler 1
Slave 4
Boiler 2
Slave 3
Slave 2
Lead Lag
Master and
Slave 1 Slave 6
Boiler 3
Slave 5
Slave 8
Boiler 4
Slave 7
Addr
1
Addr
2
Addr
3
Addr
4
Addr
5
Addr
6
Addr
7
Addr
8
Fig. 2 – Lead/Lag Arrangement in a Multiple-
Boiler Installation
On a multiple-boiler installation, each of the
individual boilers is still set up as shown in Fig. 1
above, but the controller/burner pairs on all of the
boilers are arranged in a “daisy chain.”
Up to four boilers, with up to eight controller/burner
pairs, can be connected in this way. See Fig. 2.
In all NeoTherm LC multiple-boiler installations,
just one of the Touch Screens is active. It can
communicate with all of the controller/burner pairs
in the system, so it displays information from all of
the burners. A single system sensor provides the
control input for the system.
All NeoTherm LC’s that are set up as a single
boiler will still uses a Lead/Lag operation. If the
heating load becomes too great for the first burner,
the control system automatically starts the second
burner.
To work with this control system, you will need
to understand the difference between two kinds of
control functions:
•
SYSTEM FUNCTIONS, Some of the
functions control all of the controller/burner
pairs, working together as part of the Lead/
Lag system. As an example, the setpoint for a
whole multiple-boiler system is set by a single
value: “Central Heat Lead/Lag Setpoint.”
By changing this one value, you change the
setpoint used by the whole system. The action
of all of the controller/burner pairs will refer
back to that single value.
On the Touch Screen, from the ‘home’ screen
you can reach all of the Lead/Lag functions by
pressing the View Lead Lag button. See Fig. 3.
• INDIVIDUAL FUNCTIONS, Other functions
apply only to each separate controller/burner
pair. As an example, each controller/burner has
a name, and this can be changed.
The ‘home’ screen on the Touch Screen will
show icons for each of the controller/burner
pairs connected to the system. To reach one
of the functions for an individual controller/
burner, press the icon for that controller/
burner. On the following screen, press the
Configure button. This will take you to all of
the configuration options for that individual
controller/burner.
Press here to
see current
Lead/ Lag
performance
Press here
for individual
controller/
burner pairs
Press here
for Lead/ Lag
setup
Press here for
system setup
Fig. 3 – Going to Lead/Lag and Individual
Functions
Note – For individual functions, if you want to make
a change on all of the controller/burner pairs in the
system, you will have to go to each controller/burner
separately and repeat the change for each of them.
If there are eight controller/burners in the system,
and you want to make the same change on all of
them, go to each of the eight controller/burner pairs
separately.
As we go through the explanations in this manual,
we will point out whether a control function affects
the whole Lead/Lag system, or just an individual
controller/burner pair.
This has been just a quick introduction, but this