Lennox XC16?024, XC16-036, XC16-048, XC16-060, XC16 Series Unit Information
...
Page 1
©2006 Lennox Industries Inc.
Corp. 0625−L5
XC16
Service Literature
Revised 07−2006
XC16 SERIES UNITS
The XC16 is a high efficiency residential split−system condensing unit, which features a two speed scroll compressor
and R−410A refrigerant. XC16 units are available in 2, 3, 4
and 5 tons. XC16 units are rated for 230 volts only. Applications where supply voltage is less requires a hard start kit.
The series is designed for use with an expansion valve (approved for use with R−410A) in the indoor unit. This manual
is divided into sections which discuss the major components, refrigerant system, charging procedure, maintenance and operation sequence.
Information contained in this manual is intended for use by
qualified service technicians only. All specifications are subject to change.
WARNING
Improper installation, adjustment, alteration, service
or maintenance can cause property damage, personal injury or loss of life. Installation and service must
be performed by a qualified installer or service
agency.
WARNING
Warranty will be voided if covered equipment is removed from original installation site. Warranty will
not cover damage or defect resulting from:
Flood, wind, lightning, or installation and operation
in a corrosive atmosphere (chlorine, fluorine, salt,
recycled waste water, urine, fertilizers, or other damaging chemicals).
DANGER
Shock Hazard
Remove all power at disconnect
before removing access panel.
Single phase XC16 units use singlepole contactors. Potential
exists for electrical shock resulting
in injury or death.
Line voltage exist at all components
(even when unit is not in operation).
IMPORTANT
Operating pressures of this R−410A unit are higher
than pressures in R−22 units. Always use service
equipment rated for R410A.
TABLE OF CONTENTS
General Page 1. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Specifications / Electrical Data Page 2. . . . . . . . .
I Application Page 3. . . . . . . . . . . . . . . . . . . . . . . . .
II Unit Components Page 3. . . . . . . . . . . . . . . . . .
III Refrigeration System Page 11. . . . . . . . . . . . . . .
IV Charging Page 12. . . . . . . . . . . . . . . . . . . . . . . . .
V Service and Recovery Page 16. . . . . . . . . . . . . .
VI Maintenance Page 16. . . . . . . . . . . . . . . . . . . . . .
VII Wiring and Sequence of Operation Page 17. .
Page 2
SPECIFICATIONS
General
Model No. XC16−024 XC16−036 XC16−048 XC16−060
Data
Nominal Tonnage 2
3 4 5
Connections
Liquid line (o.d.) − in. 3/8 3/8 3/8 3/8
(sweat)
Suction line (o.d.) − in. 3/4
7/8 7/8 1−1/8
Refrigerant
1
R−410A charge furnished 7 lbs. 5 oz. 8 lbs. 9 oz. 11 lbs. 4 oz. 14 lbs. 2 oz.
Outdoor
Net face area − sq. ft. Outer coil 13.22 16.33 21.00 24.93
Coil
Inner coil 12.65
15.76 20.27 24.14
Tube diameter − in. 5/16 5/16 5/16 5/16
No. of rows 2 2 2 2
Fins per inch 22 22 22 22
Outdoor
Diameter − in. 18 22 22 26
Fan
No. of blades 3
4 4 3
Motor hp 1/10 1/6 1/4 1/3
Cfm 2320 3060 3955 4380
Rpm 1130 845 835 850
Watts 165 215 320 280
Shipping Data − lbs. 1 pkg. 208 238 268 323
ELECTRICAL DATA
Line voltage data − 60hz
4
230V−1ph
4
230V−1ph
4
230V−1ph
4
230V−1ph
3
Maximum overcurrent protection (amps) 20 35 45 55
2
Minimum circuit ampacity 13.6 22.0 28.2 33.9
Compressor Rated load amps 10.3 16.7 21.2 25.6
p
Locked rotor amps 52 82 96 118
Power factor 0.98 0.99 0.99 0.99
Outdoor Fan
Full load amps 0.7 1.1 1.7 1.8
Motor
Locked Rotor amps 2
2.1 3.1 2.9
OPTIONAL ACCESSORIES − must be ordered extra
Compressor Hard Start Kit 10J42
p
81J69
Compressor Low Ambient Cut−Off 45F08
Compressor Time−Off Control 47J27
Freezestat 3/8 in. tubing 93G35
5/8 in. tubing 50A93
Indoor Blower Relay 40K58
Low Ambient Kit 68M04
SignatureStatt Home Comfort Control 81M27
Refrigerant
Line Sets
L15−41−20
L15−41−30
L15−65−40
L15−65−50
L15−65−30
L15−65−40
L15−65−50
Field Fabricate
Time Delay Relay 58M81
NOTE − Extremes of operating range are plus 10% and minus 5% of line voltage.
1
Refrigerant charge sufficient for 15 ft. length of refrigerant lines.
2
Refer to National or Canadian Electrical Code manual to determine wire, fuse and disconnect size requirements.
3
HACR type breaker or fuse.
4
Hard start kit is required in applications where the supply voltage is less than 230V.
Page 3
I − APPLICATION
XC16 condensing units are available in 2, 3, 4 and 5 ton capacities. All major components (indoor blower and coil) must be
matched according to Lennox recommendations for the compressor to be covered under warranty. Refer to the Engineering Handbook for approved system matchups.
II − UNIT COMPONENTS
Unit components are illustrated in figure 1.
XC16 PARTS ARRANGEMENT
FIGURE 1
DUAL CAPACITOR
CONTACTOR
OUTDOOR FAN
COMPRESSOR
HIGH
PRESSURE
SWITCH
FILTER DRIER
LOW
PRESSURE
SWITCH
CAUTION
To prevent personal injury, or damage to panels, unit
or structure, be sure to observe the following:
While installing or servicing this unit, carefully stow
all removed panels out of the way, so that the panels
will not cause injury to personnel, nor cause damage
to objects or structures nearby, nor will the panels be
subjected to damage (e.g., being bent or scratched).
While handling or stowing the panels, consider any
weather conditions, especially windy conditions, that
may cause panels to be blown around and battered.
Remove the louvered panels as follows:
1 − Remove 2 screws, allowing the panel to swing open
slightly (see figure 2).
Detail
A
Detail C
Detail
B
FIGURE 2
Removing/Installing Louvered Panels
MAINTAIN MINIMUM PANEL ANGLE (AS CLOSE TO PARALLEL WITH THE UNIT
AS POSSIBLE) WHILE INSTALLING PANEL.
PREFERRED ANGLE
FOR INSTALLATION
Detail D
ROTATE IN THIS DIRECTION;
THEN DOWN TO REMOVE PANEL
SCREW
HOLES
ANGLE MAY BE TOO
EXTREME
HOLD DOOR FIRMLY TO THE HINGED
SIDE TO MAINTAIN
FULLY−ENGAGED TABS
LIP
IMPORTANT! Do not allow panels to hang on unit by top tab. Tab
is for alignment and not designed to support weight of panel.
Panel shown slightly rotated to allow top tab to exit (or enter) top
slot for removing (or installing) panel.
2 − Hold the panel firmly throughout this procedure. Ro-
tate bottom corner of panel away from hinge corner post
until lower 3 tabs clear the slots (see figure 2, Detail B).
3 − Move panel down until lip of upper tab clears the top slot
in corner post (see figure 2, Detail A).
Page 4
Position and Install PanelPosition the panel almost parallel with the unit (figure 2, Detail D) with the screw side" as
close to the unit as possible. Then, in a continuous motion:
Slightly rotate and guide the lip of top tab inward (figure 2,
Details A and C); then upward into the top slot of the
hinge corner post.
Rotate panel to vertical to fully engage all tabs.
Holding the panel’s hinged side firmly in place, close the
right−hand side of the panel, aligning the screw holes.
When panel is correctly positioned and aligned, insert the
screws and tighten.
A − Control Box (Figure 3)
XC16 units are not equipped with a 24V transformer. All 24
VAC controls are powered by the indoor unit. Refer to wiring diagram.
Electrical openings are provided under the control box cover. Field thermostat wiring is made to color-coded pigtail
connections.
ELECTROSTATIC DISCHARGE (ESD)
Precautions and Procedures
CAUTION
Electrostatic discharge can affect electronic components. Take precautions during unit installation
and service to protect the unit’s electronic controls.
Precautions will help to avoid control exposure to
electrostatic discharge by putting the unit, the control and the technician at the same electrostatic potential. Neutralize electrostatic charge by touching
hand and all tools on an unpainted unit surface before performing any service procedure.
FIGURE 3
DUAL CAPACITOR
(C12)
COMPRESSOR
CONTACTOR
(K1)
CONTROL BOX
GROUNDING
LUG
TIMED OFF
CONTROL.
(OPTION)
1 − Compressor Contactor (K1)
The compressor is energized by a single−pole contactor located in the control box. See figure 3. K1 is energized by the
indoor thermostat terminal Y1 (24V) when thermostat demand is present.
2 − Dual Capacitor (C12)
The compressor and fan in XC16 series units use permanent split capacitor motors. The capacitor is located inside the unit control box (see figure 3). A single dual" capacitor (C12) is used for both the fan motor and the compressor (see unit wiring diagram). The fan side and the
compressor side of the capacitor have different MFD ratings. See side of capacitor for ratings.
3 − Start Kit (option)
The start kit consists of a potential relay K31 and start capacitor C7. The potential relay controls the operation of the
starting circuit. The relay is normally closed when contactor
K1 is de−energized. When K1 is energized, the compressor
immediately begins start up. K31 remains closed during
compressor start up and and start capacitor C7 remains in
the circuit. When compressor reaches approximately 75%
of its speed, K31 is energized. When K31 energizes, the
contacts open and start capacitor C7 is taken out of the circuit.
4 − Timed Off Control TOC (option)
The time delay is electrically connected between thermostat
terminal Y and the compressor contactor. Between cycles,
the compressor contactor is delayed for 5 minutes ± 2 min-
utes but may last as long as 8 minutes. At the end of the
delay, the compressor is allowed to energize. When thermostat demand is satisfied, the time delay opens the circuit to
the compressor contactor coil and the compressor is de−energized.
Page 5
B − Two−Stage Scroll Compressor (B1)
CAUTION
In order to avoid injury, take precaution when
lifting heavy objects.
FIGURE 1
TWO−STAGE MODULATED SCROLL
solenoid actuator coil
slider ring
The scroll compressor design is simple, efficient and requires few moving parts. A cutaway diagram of the scroll
compressor is shown in figure 1.The scrolls are located in
the top of the compressor can and the motor is located just
below. The oil level is immediately below the motor.
The scroll is a simple compression concept centered around
the unique spiral shape of the scroll and its inherent properties. Figure 2 shows the basic scroll form. Two identical
scrolls are mated together forming concentric spiral shapes
(figure 3 ). One scroll remains stationary, while the other is
allowed to orbit" (figure 4). Note that the orbiting scroll does
not rotate or turn but merely orbits" the stationary scroll.
FIGURE 2
SCROLL FORM
FIGURE 3
STATIONARY
SCROLL
ORBITING SCROLL
DISCHARGE
SUCTION
CROSS−SECTION OF SCROLLS
TIPS SEALED BY
DISCHARGE PRESSURE
DISCHARGE
PRESSURE
The counterclockwise orbiting scroll draws gas into the outer
crescent shaped gas pocket created by the two scrolls (figure
4 − 1). The centrifugal action of the orbiting scroll seals off the
flanks of the scrolls (figure 4 − 2). As the orbiting motion continues, the gas is forced toward the center of the scroll and the
gas pocket becomes compressed (figure 4 −3). When the
compressed gas reaches the center, it is discharged vertically into a chamber and discharge port in the top of the compressor (figure1). The discharge pressure forcing down on
the top scroll helps seal off the upper and lower edges (tips) of
the scrolls (figure 3 ). During a single orbit, several pockets of
gas are compressed simultaneously providing smooth continuous compression.
The scroll compressor is tolerant to the effects of liquid return. If liquid enters the scrolls, the orbiting scroll is allowed
to separate from the stationary scroll. The liquid is worked
toward the center of the scroll and is discharged. If the compressor is replaced, conventional Lennox cleanup practices
must be used.
Due to its efficiency, the scroll compressor is capable of
drawing a much deeper vacuum than reciprocating compressors. Deep vacuum operation can cause internal fusite
arcing resulting in damaged internal parts and will result in
compressor failure. This type of damage can be detected
and will result in denial of warranty claims. The scroll compressor can be used to pump down refrigerant as long as
the pressure is not reduced below 7 psig.
The scroll compressors in all XC16 model units are designed for use with R410A refrigerant and operation at high
pressures. Compressors are shipped from the factory with
3MA (32MMMA) P.O.E. oil. See electrical section in this
manual for compressor specifications.
NOTE − During operation, the head of a scroll compressor
may be hot since it is in constant contact with discharge
gas.
Page 6
TWO−STAGE OPERATION
NOTE − During operation, the head of a scroll compressor
may be hot since it is in constant contact with discharge
gas.
The two−stage scroll compressor operates like any standard
scroll compressor with the exception the two−stage compressor modulates between first stage (low capacity
approximately 67%) and second stage (high capacity).
Modulation occurs when gas is bypassed through bypass
ports (figure 5 bypass ports open) in the first suction pocket.
This bypassing of gas allows the compressor to operate on
first stage (low capacity) if thermostat demand allows. Indoor thermostat setting will determine first or second stage
operation. The compressor will operate on first−stage until
demand is satisfied or the indoor temperature reaches the
thermostat set point calling for second−stage.
Second−stage (high capacity) is achieved by blocking the
bypass ports (figure 5 bypass ports closed) with a slider ring.
The slider ring begins in the open position and is controlled
by a 24VDC internal solenoid. On a Y2 call the internal solenoid closes the slider ring, blocking the bypass ports and
bringing the compressor to high capacity. Two−stage modulation can occur during a single thermostat demand as the
motor runs continuously while the compressor modulates
from first−stage to second− stage.
FIGURE 4
SCROLL
HOW A SCROLL WORKS
SUCTION
SUCTION
SUCTION
MOVEMENT OF ORBIT
STATIONARY SCROLL
ORBITING
CRESCENT
SHAPED GAS
POCKET
HIGH
PRESSURE
GAS
DISCHARGE
POCKET
FLANKS
SEALED BY
CENTRIFUGAL
FORCE
12
3
4
SUCTION
INTERMEDIATE
PRESSURE
GAS
SUCTION
POCKET
FIGURE 5
Bypass Ports
Closed
High Capacity
Bypass Ports
Open
67% Capacity
TWO STAGE MODULATION
Loading...