036-21540-001-A-0503
Unitary Products Group
3
GENERAL INFORMATION
Our units are designed to meet the ever-changing
(unique) installation requirements of today's market. All
models 3 to 15 tons are shipped as factory-charged
unitized packages. The 20 and 25 ton models are
shipped as separate condensing unit and evaporator
section modules. These units are designed to allow
easy passage through doors, hallways and elevators.
All models are designed for freestanding mounting on
the floor, or on a field fabricated structural steel stand.
All unit components are securely mounted inside the
heavy gauge "Galvalume" steel cabinet. All units are
lined with 1/2" thick - 2 lb. density acoustical insulation
to ensure the quietest operation. All models are pro-
vided with medium-efficiency 2" thick throwaway filters.
The 3, 4, 5, 8, and 10 ton models are shipped with ver-
tical evaporator fan discharge as standard. The 12, 15,
20 and 25 ton models are shipped with horizontal fan
discharge as standard. The evaporator fan discharge
configuration is field convertible on all units.
The 3, 4, 5 ton models have a single refrigerant circuit.
The 8 through 20 ton models are dual compressor units
with two independent refrigerant circuits. The 25 ton
unit features three independent refrigeration circuits.
Evaporator and condenser coils are of copper tube and
rippled aluminum plate fin construction. All models are
equipped with an adjustable thermal expansion valve
(with external equalizer), one valve per circuit. Each
refrigerant circuit is also equipped with a liquid line filter
drier, sight glass/moisture indicator, and service access
ports. The 20 and 25 ton models require field connec-
tion and charging of the refrigerant circuits. The 20 and
25 ton models are shipped with a nitrogen holding
charge only.
High efficiency Scroll compressors are used in all mod-
els mounted on durable rubber isolator pads to reduce
vibration and noise while operating. Each refrigerant
circuit is equipped with high pressure and low-pressure
switches. An electrically re-settable lockout relay will
shut off the compressor in the event of pressure switch
trip during operation. Control circuit operates on 24V,
and features an oversized transformer. Optional anti-
short circuit timers can be field/factory installed.
Installation time is minimized with all models. When
planning an installation consider power supply, thermo-
stat, condensate drain line, duct run, and service clear-
ances. A remote thermostat device is field supplied and
installed to control the unit operation. Attachments to
the unit include the bolt-on filter frame, factory supplied
duct flanges, and an optional hydronic heating coil.
Service access doors are equipped with lifting handles,
and are located on all sides of the unit to allow easy
servicing of all components. The compressor access
door is supplied with knockouts allowing gauge lines to
be installed and readings to be taken with the machine
in operation. In addition there are removable viewing
ports to allow observation of the sight glass without
removing the access door.
All units are equipped with centrifugal blowers com-
bined with variable pitch adjustable pulleys. Forward
curved double width, double inlet blowers are used for
both condenser and evaporator air movement. All mod-
els employ a draw-through air flow arrangement. Large
evaporator and condenser coil face areas reduce noise
levels, air pressure drops, and minimize potential con-
densate blow-off. All blower wheels are galvanized
steel, with solid steel shafts supported in permanently
lubricated ball bearings. V-belts drive all models and
blower RPM can be adjusted through the motor
sheave.
Units will operate reliably at outdoor ambient down to
60
°
F. In applications requiring operation below this
temperature, a low ambient damper accessory is avail-
able. The damper installs on the condenser air dis-
charge, and allows operation to 0
°
F ambient.
Only qualified personnel should perform installation
and service of units.
