Johnson Controls ZY Series, Installation Manual

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Filters
Two-inch filters are supplied with each unit. Four-
inch filters may be used with no modification to the
filter racks. Filters must always be installed ahead of
evaporator coil and must be kept clean or replaced
with same size and type. Dirty filters reduce the
capacity of the unit and result in frosted coils or
safety shutdown. Refer to Physical Data tables for
the number and size of filters needed for the unit.
The unit should not be operated without filters
properly installed.
Power and control wiring
Field wiring to the unit, fuses, and disconnects must
conform to provisions of National Electrical Code
(NEC), ANSI/NFPA No. 70 – Latest Edition (in U.S.A.),
current Canadian Electrical Code C221, and/or local
ordinances. The unit must be electrically grounded
in accordance with NEC and CEC as specified above
and/or local codes.
Voltage tolerances which must be maintained at the
compressor terminals during starting and running
conditions are indicated on the unit Rating Plate and
Table 1.
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 Figures Figure 11 thru Figure 15 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.
CAUTION
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 inch
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. Eight (8) color-coded, insulated wires
should be used to connect the thermostat to the
unit. Refer to Table 8 for control wire sizing and
maximum length.
INSTALLATION MANUAL ZY SERIES 3 - 10 ton 60 Hertz R-410A 25
Johnson Controls Ducted Systems