Fig. 11 — Weatherproof Cover Installation
All Units —
Voltage to compressor terminals during operation must be within voltage range indicated on unit nameplate. See Table 5. On 3-phase units, voltages between phases must be balanced within 2% and the current within 10%. Use the formula shown in the legend for Table 5, Note 5 (see page 13) to determine the percent of voltage imbalance. Operation on improper line voltage or excessive phase imbalance constitutes abuse and may cause damage to electrical components. Such operation would invalidate any applicable Carrier warranty.
Field Control Wiring — Unit control voltage is 24 v. See Fig. 8 and the unit’s label diagram for field-supplied wiring details. Route control wires through the opening in unit’s end panel to the connections terminal board in the unit’s control box.
The 38AUZ unit requires an external temperature control device. This device can be a thermostat (field-supplied) or a PremierLink controller (available as factory-installed option or as field-installed accessory, for use on a Carrier Comfort Network or as a stand alone control).
Thermostat —
Install a Carrier-approved accessory thermostat according to installation instructions included with the accessory. For complete economizer function, select a two—stage cooling thermostat. Locate the thermostat accessory on a solid wall in the conditioned space to sense average temperature in accordance with the thermostat installation instructions.
If the thermostat contains a logic circuit requiring 24-v power, use a thermostat cable or equivalent single leads of different colors with minimum of four leads. If the thermostat does not require a 24-v source (no “C” connection required), use a thermostat cable or equivalent with minimum of three leads. 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: Typical multi-function marking. Follow manufacturer’s configuration instructions to select Y2.
Note 2: Y2 to economizer required on single-stage cooling units when integrated economizer function is desired
Note 3: Connect only if thermostat requires 24-vac power source. Field Wiring
Fig. 12 — Typical Remote Thermostat Connections
CONTROL CIRCUIT WIRING — Control voltage is 24 v. See Fig. 8 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 (38AUZ07-14 Units) — On multivoltage units, check the transformer primary wiring connections. See Fig. 13 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. 13.
Fig. 13 — Control Transformer Wiring
W1
Y2
Y1
R