YORK INTERNATIONAL
9
FORM 150.40-NM25
FIG. 3 – COMPRESSOR MOUNTING PAD
CHILLED LIQUID PIPING
GENERAL – When the unit has been located in its final
position, the unit liquid piping may be connected. Nor-
mal installation precautions should be observed in or-
der to receive maximum operating efficiencies. Piping
should be kept as free as possible of all foreign matter.
All liquid cooler piping must comply in all respects with
local plumbing codes and ordinances.
Since elbows, tees and valves decrease pump capac-
ity, all piping should be kept as simple as possible.
Hand stop valves should be installed in all lines to facili-
tate servicing.
Piping to the inlet and outlet connections of the chiller
may include high-pressure rubber hose or piping loops
to insure against transmission of vibration. This is op-
tional and the necessary components must be obtained
in the field.
Drain connections should be provided at all low points
to permit complete drainage of liquid cooler and piping
system.
A small valve or valves should be installed at the high-
est point or points in the chilled liquid 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 fol-
lowing 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.
2. The inlet and outlet cooler liquid connection sizes are
given on pages 4 and 5.
3. It is recommended that a strainer, preferably 40 mesh,
be installed in the cooler inlet line just ahead of the
cooler.
4. All chilled liquid piping 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 are recommended for installation in the inlet
and outlet water lines. One connection point (plug-
ged) is provided in each cooler nozzle. Thermometers
and gauges are not furnished with the unit and are to
be furnished by other suppliers.
6. The chilled liquid lines that are exposed to outdoor
ambients should be wrapped with a supplemental
heater cable and insulated to protect against freeze-
up during low ambient periods, and to prevent forma-
tion of condensation on lines in warm humid climates.
7. A chilled water flow switch, (either by YORK or oth-
ers) 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 pipe in
which it is to be installed. (See manufacturer’s instruc-
tions furnished with switch.) The switch is to be wired
to terminals in the control panel as shown in the WIR-
ING DIAGRAM.
WARNING: Flow switch must not be used to stop and
start chiller.
ELECTRICAL WIRING
The YORK Series YCA Packaged Liquid Chillers are
shipped with all contained controls wired for operation.
Field Wiring – Power wiring must be provided through a
fused disconnect switch. Minimum circuit ampacity and
maximum dual element fuse size are given on the vari-
ous Wiring Diagrams. A 115-1-60/50, 30 amp source
must be field supplied for the control panel through a
fused disconnect when a control panel transformer (op-
tional) is not provided. Refer to Wiring Diagrams.
Affiliated apparatus, such as a chilled water flow switch,
auxiliary contacts from the chilled water pump starter,
alarms, etc., should be interlocked into the control panel
circuit. These field modifications may be made as shown
on the WIRING DIAGRAMS.
MULTIPLE UNITS
For increased compressor protection and to reduce
power inrush at start-up on multiple chiller installations,
provisions must be made to prevent simultaneous start-
up of two or more units. Also, some method must be
employed to automatically cycle on or off one or more of
the units to permit more efficient operation at part load
conditions. A sequencing kit may be acquired through
your local YORK representative.
00016TG
