Emerson SL-19534 Connecting the Dual Unit Controller to an Electronic Thermostat, Installation

Installation

1.0INSTALLATION

The optional Dual Unit Control is designed to control two InteleCool or two InteleCool2® units in a lead/lag fashion. The control contains an electronic timer for switching the operating sequence of two units at intervals of one, two, four or eight days.

It also contains a two-stage heat/two-stage cool electronic thermostat with individual heat and cool setpoints. Light emitting diodes (LEDs) indicate Lead Unit 1 or 2 and power to Unit 1 or Unit 2. If required for service, thelead/lag unit may be selected manually with the P2 jumper on the Dual Unit Control board.

1.1Connecting the Dual Unit Controller to an Electronic Thermostat

The instructions below refer to Liebert’s original InteleCool and newer InteleCool2.

1.1.1Connecting the Dual Unit Controller to an InteleCool2

1.Install and level the Dual Unit Control. Leveling is not critical because the electronic thermostat does not contain mercury-filled limit switches.

2.Wire the InteleCool2 Units to the Dual Unit Control using industry standard thermostat cable. Each IntlelCool2 will need at least 4 conductor, 20 gauge copper, Class 2 wire for distances up to 50 feet (15.2m). Use 18 gauge copper, Class 2 wire for distances between 50 and 75 feet

(15.2 - 22.9m).

3.Wire the Dual Unit Control per the diagram on the inside cover of the Dual Unit Control. The InteleCool2 to Dual Unit Control low voltage control wiring connections are:

InteleCool2 Terminals	Dual Unit Control Terminals
R - 24 VAC	R
1 - 24 VAC RTN	1/2
W - Heating	W
G - Evaporator Fan	See Step 4 below
Y - Cooling	Y

4.Each InteleCool2 MUST have a jumper wire installed between terminals "G" and "Y". This ensures that the fan will energize on a call for cooling.

For continuous operation of InteleCool2 unit evaporator fans, the “G” and “R” terminals may be connected. In this mode the jumper between the “G” and “Y” terminals should be removed, and the lead/lag function will control only the condenser fans, compressors, and heaters.

5.Tighten and check all connections for correct installation.

6.Refer to the thermostat user manual for setup and operation of the electronic thermostat.

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