Section 2: Product Description; Introduction; General System Description - York YLAA0041 Installation Operation & Maintenance

Form 150.72-ICOM6
Issue date: 12/19/2023

Introduction

YORK YLAA Air-Cooled Scroll Chillers provide
chilled water for all air conditioning applications us-
ing central station air handling or terminal units. They
are completely self-contained and are designed for
outdoor (roof or ground level) installation. Each com-
plete packaged unit includes hermetic scroll compres-
sors, a liquid cooler, air cooled condenser, a charge of
Zero Ozone Depletion Potential Refrigerant R-410A or
R-454B and a weather resistant microprocessor control
center, all mounted on a rugged steel base.
The units are completely assembled with all intercon-
necting refrigerant piping and internal wiring, ready
for field installation.
Before delivery, the packaged unit is pressure-tested,
evacuated, and fully charged with refrigerant and oil.
After assembly, a complete operational test is per-
formed with water flowing through the cooler to ensure
that the refrigeration circuit operates correctly.
The unit structure is heavy-gauge, galvanized steel.
This galvanized steel is coated with baked-on powder
paint, which, when subjected to ASTM B117 1000
hour, salt spray testing, yields a minimum ASTM 1654
rating of 6. Units are designed in accordance with
NFPA 70 (National Electric Code), ASHRAE/ANSI 15
Safety code for mechanical refrigeration, ASME, and
rated in accordance with ARI Standard 550/590.
Johnson Controls

Section 2: Product description

General system description

Compressors
The chiller has suction-gas cooled, hermetic, scroll
compressors. The YLAA compressors incorporate a
compliant scroll design in both the axial and radial
direction. All rotating parts are statically and dynami-
cally balanced. A large internal volume and oil res-
ervoir provides greater liquid tolerance. Compressor
crankcase heaters are also included for extra protection
against liquid migration.
Cooler: Evaporator
The cooler is a direct expansion type with refrigerant
inside high-efficiency copper tubes. The liquid flowing
through the cooler is forced over the tubes by water
baffles.
The water baffles are constructed of galvanized steel
to resist corrosion. The removable heads allow access
to the internally enhanced, seamless copper tubes. Vent
and drain connections are included.
Water inlet and outlet connections are grooved for
compatibility with field supplied ANSI/AWWA C-606
couplings.
The cooler is equipped with a heater controlled by a
separate thermostat. The heater provides freeze pro-
tection for the cooler, down to -20ºF (-29ºC) ambient
temperature. The cooler is covered with 3/4 in. flex-
ible, closed cell, foam insulation (K = 0.25).
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