LAARS Mighty Therm2 MT2V (Sizes 200, 300, 400) - Install and Operating Manual - Manual (Page 24)

LAARS Heating Systems Page 24
Figure 15. Wiring Diagram, Boiler or Water Heater.
- +
ST.1 6V
PUMP STATUS SWITCH
ST.2 6V + -
NO
C
NC
1 P
SENSOR
P2 1 2
BL
Y
Y
Y
R
NO
C
TB1
L1
PUMP
PUMP LOAD MUST NOT EXCEED 5 AMPS.
BL R BK
FIELD WIRING
Off On
1 2 3 4 5
3.6
2.0
0.4
SWITCHED 120 VAC TO PUMP 120 VAC L DHW CALL COM CALL HEAT CALL OUT COM SYS BOILER SENSOR 4
3
2
1
POWER
HEAT CALL DHW CALL
WWSD
CURVE/ SETPOINT
CONNECTOR SHOWN FROM REAR OF BOARD
BK
R/W
IGNITOR
V/W
R/BK
R/BK
BK
R
Y
Y
FIELD FIELD
+24 -24 -24
R/BK
BL
Y R
BL/W
Y/BLK
BL/R
W W
Y/BLK
GY/V
BK
GY/BK
GY/BK
V/W
V/W
BR/R
BR/BK
BR/BLK
BR/BLK
R
BK
R/BK
BR/BK BR/R
Y
R
G
G
G
G
BK W
W
W
POWER
BK
BK
BK BK
BK
BK
BK
BK
BL/R
BL/R
BK
STAGE 2
GAS VALVE
STAGE 1
GAS VALVE
IGN/FS
E0253400
VAL
IGN 240
L1
PSW
GND
F1
F2
24 VAC
TH
FC
+ -
IGN 120
L2
HIGH
TEMPERATURE
LIMIT
MANUAL RESET
RELAY
FOR
2-STAGE
FLOW SWITCH
FIELD
INTERLOCK
L2
+24
W
MANUAL RESET
TEMPERATURE LIMIT
SWITCH
FOR SIZE 200 ONLY
PRESSURE
SWITCH
AIR
BOX/BURNER
VENT STACK PRESSURE
SWITCH
BLOWER
TRANSFORMER 115 VAC INPUT 24 VAC OUTPUT
BL/R
24V 115V
F1
BL/R
FUSE
W
OUT DOOR SENSOR
NOTES:
DOTTED LINES ARE FOR TWO STAGE ONLY.
1.
PUMP MAY BE FIELD-SUPPLIED
2.
Y
Y BL
BL/R
OPTIONAL
LWCO
6 5 3 4 2 1