Installation & Operation Manual
47
8
Field wiring
(continued)
Low voltage connections
1.
Route all low voltage wires through the knockouts in the
rear of the water heater, as shown in FIG. 8-2.
2.
Connect low voltage wiring to low voltage connection
board as shown in FIG. 8-3 on page 49 of this manual and
the water heater wiring diagram.
Figure 8-2
Routing Field Wiring (Models 150 - 285)
Thermostat
If a tank thermostat is used, connect it to the tank thermostat
terminals on the low voltage connection board (see FIG. 8-3
on page 49).
Tank sensor
If a tank sensor is used, connect it to the tank sensor terminals
on the low voltage connection board (see FIG. 8-3 on page
49). If using a tank sensor you MUST use the sensor provided
with the water heater.
High gas pressure switch
1.
If a switch is provided to detect excessive gas pressure,
remove the jumper wire from the terminals on the
connection board, and then connect them to its normally
closed contacts (FIG. 8-3).
Low gas pressure switch
1.
If a switch is provided to detect low gas pressure, remove the
jumper wire from the terminals on the connection board
and connect them to its normally open contacts (FIG. 8-3).
2.
If both a high and low gas pressure switch are used, connect
their respective contacts in series, and connect them to the
terminals on the connection board (FIG. 8-3).
Flow switch
1.
A flow switch is used to guarantee flow through the water
heater before allowing it to fire. The flow switch must be
installed in line with the water heater.
2.
Connect these terminals to the normally open contacts on
the flow switch (FIG. 8-3).
Water heater Building Management
System (BMS)
1.
An external control may be connected to control either the
firing rate or the set point of the water heater. Connect the
tank thermostat terminals to the enable output of the
external control and connect the 0 - 10 VDC terminals to
the 0 - 10 VDC output of the external control.
2.
Make sure the ground terminal is connected to the ground
output terminal of the external control, and the 0 - 10 VDC
terminal is connected to the 0 - 10 VDC terminal of the
external control.
Auxiliary device relay
1.
If an auxiliary device needs to operate when the water
heater fires, it can be controlled by this output. Connect
these terminals to a 24 VAC relay coil, which is wired to
operate the auxiliary device (FIG. 8-3).
Auxiliary device proving switch
1.
When the operation of an auxiliary device needs to be
verified before the water heater fires, remove the jumper
wire from these terminals and connect them to the
normally open contacts on its proving switch (FIG. 8-3).
NOTICE
See
Section 7 - Gas Connections
for a
detailed explanation regarding high and
low gas pressure switch operation.
Summary of Contents for Armor AWL150PM
Page 71: ...Notes ...
