York YCAL0014E Series, Installation Operation & Maintenance

Page: 21 / 212

JOHNSON CONTROLS
21
FORM 150.62-NM8 (1020)
1
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 ensure 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" (YCAL0014 through 0024), 4" (YCAL0030
through 0034), 6" (YCAL0040 through 0080), or
8" (YCAL0090 through 0134).
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 and 14 of CTB1 located
in the control panel, as shown on the unit wiring
diagram.
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 N.E.C.
or local code requirements. Minimum circuit ampacity
and maximum dual element fuse size are given in the
Tables 2 – 6.
A 120-1-60, 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 Fig. 2 through Fig. 6.
See Fig. 2 through Fig. 6 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 Unit Operation in Section 2 of this IOM 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.