Carrier 38AU appendix Thermostat, Control Transformer Wiring

Thermostat —

Install a Carrier-approved accessory thermostat according to installation instructions included with the accessory. Locate the thermostat accessory on a solid wall in the conditioned space to sense average temperature in accordance with the thermostat installation instructions.

The 38AUZ is a single-circuit, two-stage cooling unit. Select a two—stage cooling thermostat, with or without supplemental heating as needed.

The 38AUD is a dual-circuit, two-stage cooling unit. Select a two—stage cooling thermostat, with or without supplemental heating as needed.

Select a thermostat cable or equivalent single leads of different colors with minimum of five leads for 38AUZ or six leads for 38AUD unit. Check the thermostat installation instructions for additional features which might require additional conductors in the cable.

For wire runs up to 50 ft. (15 m), use no. 18 AWG (American Wire Gage) insulated wire (35￿C minimum). For 50 to 75 ft. (15 to 23 m), use no. 16 AWG insulated wire (35￿C minimum). For over 75 ft. (23 m), use no. 14 AWG insulated wire (35￿C minimum). All wire sizes larger than no. 18 AWG cannot be directly connected to the thermostat and will require a junction box and splice at the thermostat.

PremierLink (accessory installation) – Refer to Form 33CS-58SI for details on connecting the PremierLink controller and its various sensors.

(Note 1)

(Note 3)

(Note 3)

(Note 2)

Note 1: Typical multi-function marking. Follow manufacturer’s configuration instructions to select Y2.

Note 2: Connect only if thermostat requires 24-vac power source.

Note 3: Connect W1 and W2 if supplemental heaters are installed Field Wiring

C10208

Fig. 17 - Typical Remote Thermostat Connections

— 38AUZ

(Note 1)

(Note 3)

(Note 3)

(Note 2)

38AU

Note 1: Typical multi-function marking. Follow manufacturer’s configuration instructions to select Y2.

Note 2: Connect only if thermostat requires 24-vac power source.

Note 3: Connect W1 and W2 if supplemental heaters are installed Field Wiring

C10078

Fig. 18 - Typical Remote Thermostat Connections

— 38AUD

Control Circuit Wiring —

Control voltage is 24 v. See Fig. 12 and the unit’s label diagram for field-supplied wiring details. Route control wires through the opening in unit’s end panel to the connection in the unit’s control box.

Control Transformer Wiring —

On multi voltage units, check the transformer primary wiring connections. See Fig. 19 or refer to the unit’s label diagram.

If the unit will be operating at 208-3-60 power, remove the black wire (BLK) from the transformer primary connection labelled “230” and move it to the connection labelled “208”. See Fig. 19.

C10079

Fig. 19 - Control Transformer Wiring

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