24 VAC
-T
-T
-T
-T
-T
OUTDOOR
SENSOR
DHW OUTLET
SENSOR
SYSTEM
SENSOR
1
2
3
4
5
6
DISPLAY
120VAC
NEUTRAL
GROUND
120V SUPPLY "L"
120V SUPPLY "N"
INTEGRATED CONTROL
JUNCTION BOX
BOILER
PUMP "L"
BOILER
PUMP
DHW
PUMP
BOILER
PUMP "N"
F1
F2
F3
5A
3.15A
0.8A
BOILER PUMP
RELAY
DHW PUMP
RELAY
24VDC
SUPPLY
CONNECTION BOARD
INTEGRATED
CONTROL
INTEGRATED
CONTROL
CONNECTION
BOARD
X1-6
X1-3
X5-9
X5-1
X4-3
CN1-5
120 VAC
24 VAC
3
-
2
N
C
4
-
2
N
C
CN2-1
CN2-2
11
8
10
7
9
12
FLOW SWITCH
ROOM T'STAT
DHW FLOW SWITCH
CN1-14
X4-8
CN1-10
X4-12
CN1-7
X4-1
CN1-12
X4-10
DRY FIRE
SWITCH
AIR PRESSURE
SWITCH
X5-2
X5-10
X5-11
X2-2
GASVALVE
X2-1
X5-7
X5-16
X5-8
X5-15
1
2
4
5
BLOWER
TR2
X1-7
SPARK ROD
FLAME ROD
HIGH VOLTAGE SPARK LEAD
CAUTION
OPERATING
SENSOR S1a
HIGH LIMIT
SENSOR S1b
INLET
SENSOR S2
FLUE
SENSOR S3a
FLUE
SENSOR S3b
X5-6
X5-4
X5-12
X5-5
X5-13
X5-14
X6
X6
X6
X6
CN4
CN4
CN4
CN4
Notes:
1. All wiring must be installed in accordance with: local, state, provincial and national code requirements per either N.E.C. in
USA or C.S.A. in Canada.
2. If any original equipment wire as supplied with the appliance must be replaced, it must be replaced with wire having same
wire gauge (AWG) and rated for a minimum of 105°C. Exceptions: Replacement high voltage spark lead and ribbon cables
must be purchased from the factory. Use of a non-approved spark lead or ribbon cables can lead to operational problems
which could result in non-repairable damage to the integrated controller or other components.
3. Actual connector block locations may vary from those shown on diagrams. Refer to actual components for proper connector
block locations when using diagrams to troubleshoot unit.
4. Jumper OJ1 should be cut for standard altitude and connected for high altitude.
5. Jumper OJ2 should be connected for standard (non-combi) operation and cut for combi operation.
BOX DEPICTS
OPTIONAL ITEMS
BOX DEPICTS
DUAL SENSOR
SINGLE HOUSING
HIGH VOLTAGE
LOW VOLTAGE
120 VAC
LWCO
14
13
AUX SWITCH
CN1-4
X4-4
CN1-6
X4-2
CN1-13
X4-9
OJ2
OJ1
X1-2
X1-1
1
2
3
BLOWER
BLOWER
RELAY
CHASSIS
GROUND
X1-8
LADDER DIAGRAM
LBL20297 REV C
1
2
3
-T
SEE NOTE 4
SEE NOTE 5
Figure 15-3 Ladder Diagram (Combi)
15
Diagrams
(continued)
Installation & Service Manual
87