Johnson Controls YORK YCAL0043E Series, Установка, эксплуатация и обслуживание

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JOHNSON CONTROLS
12
FORM 150.62-NM9 (709)
INTRODUCTION
Hand stop valves should be installed in all lines to fa-
cilitate 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"
(YCAL0043 - 0073), 4" (YCAL0087 - 0107), 6"
(YCAL0117 - 0377).
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 Johnson
Controls or others) MUST be installed in the leav-
ing 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.
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.
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 op-
tional 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 Figures 2 - 6.
See Figures 2 - 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 section on
UNIT OPERATION for a detailed description of opera-
tion concerning aforementioned contacts and inputs.