AAON RZ Series, Installation Operation & Maintenance

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Note: All units are factory wired for
208/230V, 460V, or 575V. If unit is to be
connected to a 208V supply, the transformer
must be rewired to 208V service. For 208V
service interchange the yellow and red
conductor on the low voltage control
transformer.
Red-Black for 208V
Yellow-Black for 230V
Wire power leads to the unit’s power block or
main disconnect. All wiring beyond this point
has completed by the manufacturer and
cannot be modified without affecting the
unit’s agency/safety certification.
Figure 16 - Power Block
Supply voltage must be within the min/max
range shown on the unit nameplate. Available
short circuit current must not exceed the short
circuit current rating (SCCR) shown on the
unit nameplate.
Three phase voltage imbalance will cause
motor overheating and premature failure.
The maximum allowable imbalance is 2%.
Voltage imbalance is defined as 100 times the
maximum deviation from the average voltage
divided by the average voltage.
Example:
(221V+230V+227V)/3
= 226V, then
100*(226V-221V)/226V = 2.2%, which
exceeds the allowable imbalance.
Check voltage imbalance at the unit
disconnect switch and at the compressor
terminal. Contact your local power company
for line voltage corrections.
Installing contractor must check for proper
motor rotation and check blower motor
amperage listed on the motor nameplate is
not exceeded. Motor overload protection may
be a function of the variable frequency drive
and must not be bypassed.
Wire control signals to the unit’s low voltage
terminal block located in the controls
compartment.
Three phase voltage imbalance will
cause
motor overheating and
premature failure.
CAUTION
Rotation must be checked on all
MOTORS AND COMPRESSORS of
three phase units. Supply fan, exhaust
fan, return fan, and condenser fan
motors must all be checked by a
qualified service technician at startup
and any wiring alteration must only be
made at the unit power connection.
Variable
frequency drives are
programmed to automatically rotate
the fan in the correct rotation. Do not
rely on fans with variable frequency
drives for compressor rotation.
CAUTION