MODU-FIRE® Forced Draft Gas-Fired Boiler
43
6.1.3 MODU-FIRE® Forced Draft Boiler Wiring Diagram
!
R
E
A
R
J
U
N
C
T
IO
N
B
O
X
"
!
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
AUXILIARY
LOW WATER
CUTOFF
EXTERNAL
INTERLOCK
ENABLE
DISABLE
+
+
COM 1A
COM 1B
A
TO
A
B
TO
B
+
10
G
1
2
3
4
5
6
7
8
12
13
14
15
16
17
18
19
20
21
11
0-10V
0V
COM
FLAME
DETECTED
RELAY
MASTER
ALARM
RELAY
CIRC PUMP RELAY
120V AC
SWITCHED
OUTPUT
DHW PUMP RELAY
+
DHW PUMP RELAY
+
CIRC PUMP RELAY
+
DAMPER RELAY
DAMPER RELAY
+
+
9
L1 208-240V
G
+
3 WAY VALVE
120V AC
SWITCHED
OUTPUT
3 WAY VALVE
L2 208-240V
N 208-240V
GROUND
P
-K
M
O
D
U
-F
IR
E
F
D
7
50
-2
00
0
E
N
V
I C
on
tro
l
®
23
00
00
05
18
R
E
V
. 0
.5
TM
