York YCAS 0138EB, Installation Operation & Maintenance

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JOHNSON CONTROLS
FORM 201.18-NM7
When units are installed in an enclosure, the enclosure
height should not exceed the height of the unit on more
than one side. If the enclosure is of louvered construction
the same requirement of static pressure loss applies as
for ducts and attenuators stated above.
Where accumulation of snow is likely, additional height
must be provided under the unit to ensure normal airflow
to the unit.
The clearance dimensions given are
necessary to maintain good airflow
and ensure correct unit operation. It
is also necessary to consider access
requirements for safe operation and
maintenance of the unit and power
and control panels. Local health and
safety regulations, or practical con‑
siderations for service replacement
of large components, may require
larger clearances than those given in
the Technical Data Section, (page 96).
INSTALLATION OF VIBRATION ISOLATORS
Optional sets of vibration isolators can be supplied loose
with each unit.
Using the Isolator tables, refer to the Technical Data
Section (pages 97 - 106), identify each mount and its
correct location on the unit.
Installation
Place each mount in its correct position and lower the
unit carefully onto the mounts ensuring the mount
engages in the mounting holes in the unit base frame.
On adjustable mounts, transfer the unit weight evenly to
the springs by turning the mount adjusting nuts (located
just below the top plate of the mount) counter-clockwise
to raise and clockwise to lower. This should be done
two turns at a time until the top plates of all mounts are
between 1/4” and 1/2” (6 and 12 mm) clear of top of
their housing and the unit base is level.
A more detailed installation instruction
is provided on page 106.
SHIPPING BRACES
The chiller’s modular design does not require shipping
braces.
PIPEWORK CONNECTION
General Requirements
The following piping recommendations are intended
to ensure satisfactory operation of the unit(s). Failure
to follow these recommendations could cause damage
to the unit, or loss of performance, and may invalidate
the warranty.
The maximum flow rate and pressure
drop for the cooler must not be exceed‑
ed at any time. Refer to the Technical
Data Section for details.
The liquid must enter the cooler by the
inlet connection. The inlet connection
for the cooler is at the far end of the
unit when viewed from the power and
control panels.
A flow switch must be installed in the customer pipe -
work at the outlet of the cooler and wired back to the
control panel using shielded cable. There should be
a straight run of piping of at least 5 pipe diameters on
either side. The flow switch should be wired to Terminals
13 and 14 (see Figs. 12 and 13, pages 39 and 40). A flow
switch is required prevent damage to the cooler caused
by the unit operating without adequate liquid flow.
The flow switch used must have gold plated contacts for
low voltage/current operation. Paddle type flow switches
suitable for 150 PSIG (10 bar) working pressure and hav-
ing a 1” N.P.T. connection can be obtained from YORK
as an accessory for the unit. Alternatively a differential
pressure switch sited across an orifice plate may be used,
preferably of the high/low limit type.
The chilled liquid pump(s) installed in the pipework
system(s) should discharge directly into the unit cooler
section of the system. The pump(s) may be controlled
external to the unit - but an override must be wired to the
control panel so that the unit can start the pump in the
event that the liquid temperature falls below the minimum
setting. For details refer to “Electrical Connection.”
Installation