Unit Overview - York YLUA Series Operation Manual

Unit Overview

GENERAL
The 68-135 Ton (238 - 473 kW) YLUA Condensing Unit
Models are shipped complete from the factory ready for
field installation.
The unit is pressure-tested, evacuated and given a ni-
trogen holding charge and includes an initial oil charge
(R-410A refrigerant supplied by others). After assembly, a
operational test is performed to assure that each control
device 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 Elec tric Code), ASHRAE/ANSI 15 Safety code
for mechanical refrigeration, and are cETL listed. All units
are produced at an ISO 9000-registered facility.
COMPRESSORS
The chiller has suction-gas cooled, hermetic, scroll com-
pressors. The compressors incorporate a compliant scroll
4
design in both the axial and radial direction. All rotating
parts of the compressors are statically and dynamically
balanced. A large internal volume and oil reservoir pro-
vides greater liquid tolerance. Compressor crankcase
heaters are also included for extra protection against
liquid migration.
CONDENSER
Coils – Fin and tube condenser coils of seamless, inter-
nally-enhanced, high-condensing-coefficient, corrosion
resistant copper tubes are arranged in staggered rows,
mechanically expanded into aluminum fins. Integral sub-
cooling is included. The design working pressure of the
coil is 650 psig (45 barg).
Fans – The condenser fans are composed of corro-
sion-resistant aluminum hub and glass-fiber-reinforced
polypropylene composite blades molded into a low noise
airfoil section. The are designed for maximum efficiency
and are statically and dynamically balanced for vibration
free operation. They are directly driven by independent
motors, and positioned for vertical air discharge. The fan
guards are constructed of heavy-gauge, rust-resistant,
coated steel. All blades are statically and dynamically
balanced for vibration-free operation.
Motors – The fan motors are Totally Enclosed Air-Over,
squirrel-cage type, current protected. They feature ball
bearings that are double-sealed and permanently lubri-
cated.
REFRIGERANT CIRCUIT
Two inde pendent refrigerant circuits will be furnished on
each unit. All unit piping will be copper, with brazed joints.
The liquid line will include a field connection shutoff valve
with charg ing port located on each condenser circuit. Suc-
tion line connections are provided on each refrigeration
circuit. A filter drier and sight glass are shipped loose for
field installation on each refrigerant circuit.
All expansion valves, liquid line solenoid valves, refriger-
ant, and refrigerant field piping are supplied by others.
FORM 150.63-EG4 (1012)
JOHNSON CONTROLS