Thermostat Wiring - York International ZQ Series Installation Manual

CAUTION
208/230-3-60 and 208/230-1-60 units control
transformers are factory wired for 230V. Change tap
on transformer for 208V operation. See unit wiring
diagram.
The internal wiring harnesses furnished with this
unit are an integral part of the design certified
unit. Field alteration to comply with electrical codes
should not be required. If any of the wire supplied
with the unit must be replaced, replacement wire
must be of the type shown on the wiring diagram
and the same minimum gauge as the replaced wire.
A disconnect must be utilized for these units.
Factory installed disconnects are available. If
installing a disconnect (field supplied), refer to
Figure 11 and Figure 12 for the recommended
mounting location.
CAUTION
Avoid damage to internal components if drilling holes
for disconnect mounting.
Note: Since not all local codes allow the
mounting of a disconnect on the unit, please
confirm compliance with local code before
mounting a disconnect on the unit.
Electrical line must be sized properly to carry the
load. USE COPPER CONDUCTORS ONLY. Each unit
must be wired with a separate branch circuit fed
directly from the meter panel and properly fused.
CAUTION
When connecting electrical power and control wiring
to the unit, water-proof connectors must be used so
that water or moisture cannot be drawn into the unit
during normal operation. The above water-proofing
conditions will also apply when installing a field
supplied disconnect switch.
When installing equipment in a facility with a 3-phase
high-leg delta power supply, care must be taken to
ensure that the high-leg conductor is not attached to
either of the two legs of the (single phase, direct drive)
X13 or ECM motors. Failure to do so can result in the
motor acting erratically or not running at all.
Check for the high leg conductor by checking voltage
of each phase to ground.
Example: A or L1 phase to ground, voltage reading is
120V. B or L2 phase to ground, voltage reading is 195
to 208V. C or L3 phase to ground, voltage reading is
120V. Therefore B or L2 phase is the high Leg. The
high should always be wired to the center or B or L2
tap.
Note: Check all three phase motors and compressors
for proper rotation after making a change. If it is
necessary to change 3 phase motor rotation, swap A
or L1 and C or L3 only.

Thermostat Wiring

A two-stage thermostat must be used and should
be located on an inside wall approximately 56 in.
above the floor where it will not be subject to drafts,
sun exposure, or heat from electrical fixtures or
appliances. Follow the manufacturer's instructions
enclosed with thermostat for general installation
procedure. Color-coded, insulated wires should be
used to connect the thermostat to the unit. Refer to
Table 6 for control wire sizing and maximum length.
Table 6: Control Wire Sizes
Wire size
20 AWG
18 AWG
16 AWG
Note:
1.
INSTALLATION MANUAL ZQ SERIES 3 - 5 ton 60 Hertz R-410A
Johnson Controls Ducted Systems
CAUTION
Maximum length (ft)
< 150
150 to 250
250 to 500
From the unit to the thermostat and back
to the unit.
1
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