Unit installation

22 IOMM ACZ/AGZ
Electrical Data
Field Wiring
Power Wiring
CAUTION
Internal power wiring to the compressors for single and multiple point option are different.
Field wiring must be installed according to unit wiring diagram.
Wiring must comply with all applicable codes and ordinances. Warranty is void if wiring is not in
accordance with specifications. Copper wire is required for all power lead terminations at the unit.
Aluminum or copper can be used for all other wiring.
AGZ-AM and ACZ units have internal power wiring for single point power connection. A single
large power terminal block is provided and wiring within the unit is sized in accordance with the
National Electrical Code. A single field supplied fused disconnect is required. An optional factory
mounted transformer may be installed.
AGZ-AM remote water chillers and CDE chillers are equipped with a 420W electric heater to
provide freeze protection if mounted in locations subject to below freezing temperatures. The
heater comes with a receptacle plug which can be used as is, or removed to hard wire to a power
supply.
Control Wiring
AGZ-AM chillers are equipped with either a Johnson Controls UNT control or a McQuay
MicroTech microprocessor control mounted in the outdoor unit. The control sensor for capacity
control must be mounted in the leaving chilled water line in a thermowell provided in the water
chiller nozzle. A sensor well is also located in the entering nozzle for use with some control
options. The sensor is wired to the control with 30 ft. of cable. If a longer length is required, it is
necessary to field splice the cable.
ACZ condensing units are not equipped with a capacity control device and one must be field
furnished and installed. Refer to Figure 20, ACZ Field Wiring Diagram (Capacity Control Staging).
Up to four steps of control are available.
AGZ-AM and ACZ units connected to water chillers must have a flow switch mounted in the chilled
water line and wired to the control panel per the field wiring diagram. It is recommended that ACZ
units connected to DX air coils have an interlock to prevent compressor operation when there is no
air flow.