LAARS Mini-Combo id MCH - Install and Operating Manual - Manual (Page 6)

Page 6
LAARS Heating Systems
Figure 6. Wiring Diagram.
WARNING
Electrical shock can cause severe personal injury or
death. Disconnect power supply to the boiler before
doing any electrical work.
Electrical Connection (see Figures 5 and 6).
1. Remove the two screws attaching the front cover
of the control box.
2. There are six wires coiled in the area on the right
side of the control box, supplied with wire nuts:
2 black wires twisted together, 3 white wires
twisted together, and a brown wire.
3. Follow the schematics in Figures 5 and 6.
Remove the wire nut from the two black wires,
and connect the hot lead from a 115 volt power
supply to both wires. Secure the three wires in
the wire nut.
4. The three white, neutral wires should be joined
to the other neutral lead coming from the 115
volt power supply, and the neutral lead coming
from the pump (space heating).
5. The brown wire attaches to the hot side of the
space heating pump.
H2021000A
BK - BLACK
W - WHITE
R - RED
Y - YELLOW
BL - BLUE
BR - BROWN
O - ORANGE
P - PURPLE
G - GREEN
BL/Y - BLUE/YELLOW STRIPE
BR/Y - BROWN/YELLOW STRIPE
115V-FACTORY WIRED
115V-FIELD WIRED
24V-FACTORY WIRED
24V-FIELD WIRED
IF ANY OF THE ORIGINAL WIRE (AS
SUPPLIED WITH THE APPLIANCE) MUST
BE REPLACED, IT MUST BE REPLACED
WITH APPLIANCE WIRING MATERIAL
SUITABLE FOR 105 DEGREES C OR ITS
EQUIVALENT
HOT
TANK
AQUASTAT
BR
WALL
THERMOSTAT
(FIELD
SUPPLIED)
P
24V
COM
SEN
NC NO COM
TRANSFORMER
BK
24V 115V R
Y
Y
G
W
ZONE
PUMP
RELAY
GROUNDING
CONDUCTOR
NEUTRAL
115/60HZ
POWER SUPPLY
BK
BK
BR
PUMP
(FIELD
SUPPLIED)
W
TANK
PUMP
BR
TANK
PUMP
RELAY
INDUCER
BL
Y
INDUCER
MOTOR
RELAY
BR
O
P
Y
GAS VALVE
MOLEX
BL
R R
P
Y
Y
PRESSURE
SWITCH
ROLL-OUT
SAFETY
SWITCH
BL
P
O
R
HIGH
LIMIT AQUASTAT
(OPTIONAL)
SENSOR
R
BL
R
W
R
R
W
A
TERMINAL
STRIP
R R
R
1
4
3
2
6
5
R
1
4
3
2
6
5
R
1
4
3
2
6
5
MODEL MCH
BK
Y
W
4. When water discharges from the faucet,
close it. Check for system leaks and repair
if necessary.
• Filling and connecting boiler pipes:
Consult the JV boiler manual, Document 1080.
Caution
Never use water heater/boiler unless it is
completely filled with water.
2D. Wiring
Priority System: Under this wiring the storage
tank will be supplied before space heating. This will
insure that it gets adequate hot water flow from the
boiler to maintain a fully rated delivery of domestic
hot water.
Caution
In this priority mode, any demand for space heating
is postponed until the storage water tank has
reached set temperature. This delay in supplying
the space heating zones is usually not noticed by
the inhabitants of the living spaces. However, in the
event of certain storage water tank malfunctions,
space heating could be delayed indefinitely. If
undetected and un-corrected, freezing damage to
piping could result.