York MILLENNIUM YCAL0043SC, Manual

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YORK INTERNATIONAL
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FORM 150.62-NM2
Hand stop valves should be installed in all lines to
facilitate servicing.
Piping to the inlet and outlet connections of the chiller
should include high-pressure rubber hose or piping
loops to insure against transmission of water pump
vibration. The necessary components must be obtained
in the field.
Drain connections should be provided at all low points to
permit complete drainage of the cooler and system
water piping.
A small valve or valves should be installed at the highest
point or points in the chilled water piping to allow any
trapped air to be purged. Vent and drain connections
should be extended beyond the insulation to make them
accessible.
The piping to and from the cooler must be designed to
suit the individual installation. It is important that the
following considerations be observed:
1. The chilled liquid piping system should be laid out so
that the circulating pump discharges directly into the
cooler. The suction for this pump should be taken
from the piping system return line and not the cooler.
This piping scheme is recommended, but is not
mandatory.
2. The inlet and outlet cooler connection sizes are 3"
(YCAL0043 - 0087), 4" (YCAL0107 - 0173), or 6"
(YCAL0197 - 0253).
3. A strainer, preferably 40 mesh, must be installed in
the cooler inlet line just ahead of the cooler. This is
important to protect the cooler from entrance of large
particles which could cause damage to the evaporator.
4. All chilled liquid piping should be thoroughly flushed to
free it from foreign material before the system is
placed into operation. Use care not to flush any
foreign material into or through the cooler.
5. As an aid to servicing, thermometers and pressure
gauges should be installed in the inlet and outlet
water lines.
6. The chilled water lines that are exposed to outdoor
ambients should be wrapped with supplemental
heater cable and insulated to protect against freeze-
up during low ambient periods, and to prevent
formation of condensation on lines in warm humid
locations.
7. A chilled water flow switch, (either by YORK or others)
MUST be installed in the leaving water piping of the
cooler. There should be a straight horizontal run of at
least 5 diameters on each side of the switch. Adjust
the flow switch paddle to the size of the pipe in which
it is to be installed. (See manufacturer’s instructions
furnished with the switch.) The switch is to be wired to
terminals 13 – 14 of CTB1 located in the control
panel, as shown on the unit wiring diagram.
ELECTRICAL WIRING
Liquid Chillers are shipped with all factory mounted
controls wired for operation.
Field Wiring – Power wiring must be provided through
a fused disconnect switch to the unit terminals (or
optional molded disconnect switch) in accordance with
local code requirements. Minimum circuit ampacity and
maximum dual element fuse size are given in the
ELECTRICAL DATA tables.
A 115-1-50, 15 amp source must be supplied for the
control panel through a fused disconnect when a control
panel transformer (optional) is not provided. Refer to Table
1 and Figures 2 - 4.
See Figures 2 - 4 and unit wiring diagrams for field and
power wiring connections, chilled water pump starter
contacts, alarm contacts, compressor run status
contacts, PWM input, and load limit input. Refer to
section on UNIT OPERATION for a detailed description
of operation concerning aforementioned contacts and
inputs.
The Flow Switch MUST NOT be used to
start and stop the chiller (i.e. starting
and stopping the chilled water pump).It
is intended only as a safety switch.
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