Direct heating piping diagram, Modulating and sequencing boilers, System – LAARS M4-Ext - Installation Manual User Manual
Page 34: Laars heating systems, Rs-485 extension module, Ma gnd vlt, Ma temp outdoor o o temp system, Prove /dhw shutdown /setback
34
MOdULATiNg ANd SEqUENCiNg BOiLERS
diRECT HEATiNg PiPiNg diAgRAM
System:
The
M4-CNC operates 2 modulating boilers and 2 On/Off Boilers. The boilers are piped in Reverse Return on the primary
loop. The System output is controlling the System Pump.
Laars is aware that each installation is unique. Thus, Laars is not responsible for any installation related to any electrical
or plumbing diagram generated by Laars. The provided illustrations are to demonstrate Laars’s control operating concept
only.
LAARS Heating Systems
HT# 059104-00 B
Outdoor
Sensor
System
Sensor
120VAC
Boiler 1
Boiler 2
Boiler 3
Boiler 4
Building Heating Loop
RS-485
EXTENSION
MODULE
A
B
C
D
1 2
RUN
PROGRAM
DO NOT APPLY ANY VOLTAGE
TO INPUT TERMINALS
3 4 5 6 7 8 9 10 11 12
13
15
14
17
16
18
22
20
19
21
24
23
29
25
27
26
28
32
30 31
L N
-
+
+
T
T
O
O
mA
GND
VLT
SYS
A
B
C
D
PWR
CUR / VLT
A
-
+
+
mA
GND
VLT
-
+
+
mA
GND
VLT
-
+
+
mA
GND
VLT
+
mA
TEMP
OUTDOOR
O
O
TEMP
SYSTEM
CUR / VLT
B
CUR / VLT
C
CUR / VLT
D
PROVE
/DHW
SHUTDOWN
/SETBACK
FOR ALL CIRCUITS
120VAC, 6A RESISTIVE
OUTPUT RATINGS:
1A PILOT DUTY, 15A TOTAL
115VAC 60Hz , 30VA MAX
INPUT RATINGS:
USE COPPER WIRE,
CLASS 1 WIRE ONLY.
CAUTION
: RISK OF ELECTRIC SHOCK
More than one disconnect switch may be required
to de-energize the equipment before servicing.
/TSTAT
SYSTEM
M4-CNC
CONDENSING / NON-CONDENSING CONTROL
Condensing
Modulating
Condensing
Modulating
Non-Condensing
Sequencing
Non-Condensing
Sequencing
OD=
25
oF
SYS=
145
oF
<<A>>
B
<C>
D
100%
52% ---
---