Lochinvar 5 Low voltage connections, Enable, Outdoor temperature sensor, Louver proving switch

7 Field wiring (continued)

Low voltage connections

1.Route all low voltage wires through the knockouts in the rear of the boiler, as shown in FIG. 7-2.

2.Connect low voltage wiring to low voltage connection board as shown in FIG. 7-3 on page 41 of this manual and the boiler wiring diagram.

Figure 7-2Routing Field Wiring

LOW VOLTAGE

LOW VOLTAGECONNECTION BOARD

WIRING KNOCKOUTS

LINE VOLTAGE

WIRING KNOCKOUTS

Enable

1.Connect the room thermostat or boiler enable contacts (isolated contact only) to terminals R and W, as shown in FIG. 7-3.

2.If a thermostat is used, install the thermostat on the inside wall away from influences of drafts, hot or cold water pipes, lighting fixtures, television, sunlight, or fireplaces.

3.Thermostat anticipator (if applicable):

a.If connected directly to boiler, set for 0.1 amps.

b.If connected to relays or other devices, set to match total electrical power requirements of connected devices. See device manufacturers’ specifications and thermostat instructions for details.

Outdoor temperature sensor

1.Connect the outdoor temperature sensor (FIG. 7-3) to the Outdoor Sensor terminals on the connection board to enable outdoor reset operation of the SYNC.

2.Mount the sensor on an exterior wall, shielded from direct sunlight or flow of heat or cooling from other sources.

3.Route sensor wires through a knockout at the rear of the boiler (see FIG. 7-2).

Installation & Operation Manual

Hot Water Generator (HW) thermostat

1.Connect the HW tank thermostat to the Tank Thermostat terminals on the connection board (FIG. 7-3).

Hot Water Generator (HW) tank sensor

1.By installing a HW tank sensor, the SMART TOUCH control can perform the tank thermostat function. The SMART TOUCH control automatically detects the presence of this sensor, and generates a HW call for heat when the tank temperature drops 6°F (3°C) below the tank set point, and finishes the call for heat when the tank temperature reaches the tank set point.

2.A TST2032 sensor MUST be used with any indirect tank. Failure to use the correct sensor will result in the tank temperature being either above or below the set point. Connect the correct sensor to the Tank Sensor terminals (see FIG. 7-3).

Louver proving switch

1.Louvers are used to provide combustion air for the room air option. A louver proving switch should be installed on the appropriate terminals and verified prior to operation (see FIG. 7-3).

Flow switch (field supplied)

1.Flow switches are designed to prevent a no flow situation.

2.A flow switch may be used to guarantee flow through the boiler before allowing it to fire. When used, the SYNC boiler requires a flow switch to be installed on each inlet.

3.Remove the jumper wires from the terminals on the connection board and connect these terminals to the normally open contacts on the flow switches (FIG. 7-3).

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