Lennox XC21 Engineering Data

XC21 - 2 to 5 Ton Air Conditioner / Page 3
Copper Tube/Enhanced Fin Coil
Lennox designed and fabricated coil.
Ripple-edged aluminum ns.
Copper tube construction.
Lanced ns provide maximum exposure of n surface to
air stream resulting in excellent heat transfer.
Fin collars grip tubing for maximum contact area.
Flared shoulder tubing connections/silver soldering
construction.
Coil is factory tested under high pressure to insure
leakproof construction.
Entire coil is accessible for cleaning.
High Pressure Switch
Shuts off unit if abnormal operating conditions cause the
discharge pressure to rise above setting.
Protects compressor from excessive condensing
pressure.
Automatic reset.
Low Pressure Switch
Shuts off unit if suction pressure falls below setting.
Provides loss of charge and freeze-up protection.
Automatic reset.
Hi-Capacity Liquid Line Drier
Factory installed in the liquid line, the drier traps
moisture or dirt that could contaminate the refrigerant
system.
100% molecular-sieve bead type drier.
OPTIONS
Expansion Valve Kits
Must be ordered extra and eld installed on certain
indoor units. See TXV Usage table on page 13.
Chatleff style tting.
Freezestat
Installs on or near the discharge line of the indoor coil or
on the suction line.
Senses suction line temperature and cycles the
compressor off when suction line temperature falls
below it’s setpoint.
Opens at 29°F and closes at 58°F.
Refrigerant Line Kits
Refrigerant lines (suction & liquid) are shipped
refrigeration clean. Lines are cleaned, dried,
pressurized, and sealed at factory.
Suction line fully insulated.
L15 lines are stubbed at both ends.
See Specications table for selection.
Not available for -060 model and must be eld
fabricated.
D
E
F
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COMPRESSOR
Copeland Scroll Ultra Tech™ Two-Stage Compressor
Compressor features high
efciency with uniform
suction ow, constant
discharge ow and high
volumetric efciency and
quiet operation.
Compressor consists of
two involute spiral scrolls
matched together to generate
a series of crescent shaped
gas pockets between them.
During compression, one
scroll remains stationary
while the other scroll orbits
around it.
Gas is drawn into the outer
pocket, the pocket is sealed
as the scroll rotates.
As the spiral movement continues, gas pockets are
pushed to the center of the scrolls. Volume between the
pockets is simultaneously reduced.
When pocket reaches the center, gas is now at high
pressure and is forced out of a port located in the
center of the xed scrolls. During compression, several
pockets are compressed simultaneously resulting in a
smooth continuous compression cycle.
Continuous ank contact, maintained by centrifugal
force, minimizes gas leakage and maximizes efciency.
Scroll compressor is tolerant to the effects of slugging
and contaminants. If this occurs, scrolls separate,
allowing liquid or contaminants to to be worked toward
the center and discharged.
On the xed scroll there are two bypass ports in the rst
suction pocket. On the
outside of the xed scroll
there is a “slider ring” that
is controlled by an internal
solenoid that will rotate and
cover the bypass ports.
When the thermostat calls
for rst-stage cooling, the
bypass ports are open and
the compressor operates
at 67% capacity, creating
more cost-effective and efcient compressor operation.
The bypassed refrigerant is returned to the compressor
housing through the bypass ports. When the thermostat
calls for second-stage cooling, the internal solenoid is
energized, the slider ring rotates and covers the bypass
ports, and the compressor operates at full capacity.
Low gas pulses during compression reduces
operational sound levels.
Compressor motor is internally protected from
excessive current and temperature.
H
FEATURES

Lennox XC21 Specifications

General

Brand	Lennox
Model	XC21
Category	Air Conditioner
Language	English