Improper installation, adjustment, alteration,
service or maintenance can cause personal injury,
loss of life, or damage to property.
Installation and service must be performed by a
licensed professional installer (or equivalent) or a
service agency.
CAUTION
Physical contact with metal edges and corners
while applying excessive force or rapid motion can
result in personal injury. Be aware of, and use
caution when working near these areas during
installation or while servicing this equipment.
Check the unit for shipping damage and listed times below
are intact. If damaged, or if parts are missing, immediately
contact the last shipping carrier.
1 Assembled outdoor unit
1 Refrigerant flow control kit (Fixed Orifice)
Litho U.S.A.
The Clean Air Act of 1990 bans the intentional
venting of refrigerant (CFCs, HCFCs and HFCs) as
of July 1, 1992. Approved methods of recovery,
recycling or reclaiming must be followed. Fines
and/or incarceration may be levied for
noncompliance.
IMPORTANT
This unit must be matched with an indoor coil as
specified in Lennox AC13 Engineering Handbook.
10/08506109−01
*2P1008**P506109-01*
AC13 Air Conditioner Units
The AC13 Air Conditioners, which will also be referred to in
this instruction as the outdoor unit, uses HCFC−22
refrigerant. This outdoor unit must be installed with a
matching indoor unit and line set as outlined in the LennoxAC13Engineering Handbook.
This outdoor unit is designed for use in systems that use
one of the following refrigerant metering devices:
Thermal expansion valve (TXV)
Fixed orifice
Page 1
Page 2
Unit Dimensions − Inches (mm)
SUCTION LINE
CONNECTION
RUN
CAPACITOR
CONTACTOR
DISCHARGE
LINE
OUTDOOR FAN
COMPRESSOR
UNIT SUPPORT
FEET
TOP VIEW
DISCHARGE AIR
SIDE VIEW
LIQUID LINE
CONNECTION
LIQUID LINE
CONNECTIONS
SUCTION LINE
SUCTION VALVE AND
GAUGE PORT/SUCTION
LINE CONNECTIONS
This product and/or the indoor unit it is matched
with may contain fiberglass wool.
Disturbing the insulation during installation,
maintenance, or repair will expose you to fiberglass
wool dust. Breathing this may cause lung cancer.
(Fiberglass wool is known to the State of California
to cause cancer.)
Fiberglass wool may also cause respiratory, skin,
and eye irritation.
To reduce exposure to this substance or for further
information, consult material safety data sheets
available from address shown below, or contact
your supervisor.
Lennox Industries Inc.
P.O. Box 799900
Dallas, TX 75379−9900
General Information
These instructions are intended as a general guide and do
not supersede local codes in any way. Consult authorities
who have jurisdiction before installation.
When servicing or repairing HVAC components, ensure
caps and fasteners are appropriately tightened. Table 1
lists torque values for typical service and repair items.
Table 1. Torque Requirements
PartRecommended Torque
Service valve cap8 ft.− lb.11 NM
Sheet metal screws16 in.− lb.2 NM
Machine screws #1028 in.− lb.3 NM
Compressor bolts90 in.− lb.10 NM
Gauge port seal cap8 ft.− lb.11 NM
USING MANIFOLD GAUGE SETS
When checking the system charge, only use a manifold
gauge set that features low loss anti−blow back fittings.
See figure 3 for a typical manifold gauge connection setup.
OPERATING SERVICE VALVES
IMPORTANT
Only use Allen wrenches of sufficient hardness
(50Rc − Rockwell Harness Scale minimum). Fully
insert the wrench into the valve stem recess.
Service valve stems are factory−torqued (from 9
ft−lbs for small valves, to 25 ft−lbs for large valves) to
prevent refrigerant loss during shipping and
handling. Using an Allen wrench rated at less than
50Rc risks rounding or breaking off the wrench, or
stripping the valve stem recess.
The liquid and suction line service valves are used for
removing refrigerant, flushing, leak testing, evacuating,
checking charge and charging.
Each valve is equipped with a service port which has a
factory−installed valve stem.
1/12 TURN
12
1
2
3
4
7
5
6
9
10
8
11
1/6 TURN
12
1
2
3
4
7
5
6
11
10
9
8
Figure 1. Cap Tightening Distances
NOTE − A label with specific torque requirements may be
affixed to the stem cap. If the label is present, use the
specified torque listed.
IMPORTANT
To prevent stripping of the various caps used, the
appropriately sized wrench should be used and
fitted snugly over the cap before tightening.
Operating Angle−Type Service Valve
To Access Angle−Type Service Port:
A service port cap protects the service port core from
contamination and serves as the primary leak seal.
SERVICE PORT CAP
STEM CAP
SERVICE PORT
(VALVE STEM SHOWN
CLOSED) INSERT HEX
WRENCH HERE
SERVICE PORT
CLOSED TO BOTH
INDOOR AND
OUTDOOR UNITS
FRONT-SEATED
CORE
VALVE STEM
TO INDOOR
UNIT
TO OUTDOOR UNIT
Figure 2. Angle−Type Service Valve
(Font−Seated Closed)
1. Remove service port cap with an appropriately sized
wrench.
2. Connect gauge to the service port.
3. When testing is completed, replace service port cap and
tighten as follows:
With Torque Wrench: Tighten finger tight and then
tighten per table 1.
Page 3
AC13 SERIES
Page 4
OUTDOOR UNIT
OUTDOOR
COIL
(UNCASED COIL SHOWN)
TXV OR FIXED
ORIFICE
LOW
PRESSURE
GAUGE MANIFOLD
PRESSURE
TO
HCFC−22
DRUM
HIGH
LIQUID LINE
SERVICE VALVE
COMPRESSOR
Figure 3. Typical Gauge Manifold Connections
Without Torque Wrench: Finger tighten and use an
appropriately sized wrench to turn an additional
1/6 turn clockwise as illustrated in figure 1.
To Open and Close Angle−Type Service Valve:
A valve stem cap protects the valve stem from
contamination and assures a leak−free seal.
SERVICE PORT CAP
SERVICE PORT
CORE
OPEN TO BOTH
INDOOR AND
OUTDOOR UNITS
TO INDOOR
UNIT
TO OUTDOOR UNIT
STEM CAP
SERVICE PORT
(VALVE STEM SHOWN OPEN)
INSERT HEX WRENCH HERE
Figure 4. Angle−Type Service Valve
(Back−Seated Opened)
1. Remove stem cap with a wrench.
2. Use a service wrench with a hex−head extension
(3/16" for liquid-line valve sizes and 5/16" for
suction-line valve sizes) to back the stem out
counterclockwise as far as it will go.
3. Replace the stem cap and tighten as follows:
With Torque Wrench: Tighten finger tight and then
tighten per table 1.
Without Torque Wrench: Finger tighten and i\use
an appropriately sized wrench to turn an additional
1/12 turn clockwise as illustrated in figure 1.
SUCTION LINE
SERVICE VALVE
Operating Ball−Type Service Valve
To Access Ball−Type Service Port:
A service port cap protects the service port core from
contamination and serves as the primary leak seal.
1. Remove service port cap with an appropriately sized
wrench.
2. Connect gauge to the service port.
3. When testing is completed, replace service port cap and
tighten as follows:
With Torque Wrench: Tighten finger tight and then
tighten per table 1.
Without Torque Wrench: Finger tighten and use an
appropriately sized wrench to turn an additional
1/6 turn clockwise as illustrated in figure 1.
To Open and Close Ball−Type Service Valve:
A valve stem cap protects the valve stem from
contamination and assures a leak−free seal.
1. Remove stem cap with a wrench.
2. Use an appropriately sized wrench to open. To open
valve, rotate stem counterclockwise 90°. To close
rotate stem clockwise 90°.
3. Replace the stem cap and tighten as follows:
With Torque Wrench: Tighten finger tight and then
tighten per table 1.
Without Torque Wrench: Finger tighten and use an
appropriately sized wrench to turn an additional
1/12 turn clockwise as illustrated in figure 1.
NOTE − A label with specific torque requirements may be
affixed to the stem cap. If the label is present, use the
specified valve listed.
506109−01 10/08
Page 4
Page 5
OPEN TO LINE SET WHEN VALVE IS CLOSED,
TO BOTH LINE SET AND UNIT WHEN VALVE IS
OPEN.
TO OPEN ROTATE STEM
COUNTERCLOCKWISE 90°.
TO CLOSE ROTATE STEM
CLOCKWISE 90°.
SERVICE PORT
SERVICE PORT
CORE
SERVICE PORT CAP
TO OUTDOOR UNIT
TO INDOOR UNIT
BALL (SHOWN
CLOSED)
STEM CAP
VALV E
STEM
Figure 5. Ball−Type Service Valve
Recovering Refrigerant from Existing
HCFC−22 System
Remove existing HCFC−22 refrigerant using one of the
following methods:
METHOD 1:
Use this method if the existing outdoor unit is not equipped
with manual shut−off valves, and plan on using existing
HCFC−22 refrigerant to flush the system.
NOTE − Use recovery machine instructions for specific
setup requirements.
Perform the following task:
1. Disconnect all power to the existing outdoor unit.
2. Connect to the existing unit a gauge set, clean
recovery cylinder and a recovery machine. Use the
instructions provided with the recover machine on how
to setup the connections.
3. Remove all HCFC−22 refrigerant from the existing
system. Check gauges after shutdown to confirm that
the entire system is completely void of refrigerant.
RECOVERY MACHINE
CLEAN RECOVERY
CYLINDER
Figure 6. Typical Refrigerant Recovery (Method 1)
MANIFOLD GAUGES
OUTDOOR UNIT
METHOD 2:
Use this method if the existing outdoor unit is equipped
with manual shut−off valves, and plan on using new
HCFC−22 refrigerant to flush the system.
IMPORTANT: Some system configurations may contain
higher than normal refrigerant charge due to either large
internal coil volumes, and/or long line sets. The following
conditions may cause the compressor to stop functioning:
The following devices could prevent full system charge
recovery into the outdoor unit:
Outdoor unit’s high or low−pressure switches (if
applicable) when tripped can cycled the compressor
OFF.
Compressor can stop pumping due to tripped internal
pressure relief valve.
Compressor has internal vacuum protection that is
designed to unload the scrolls (compressor stops
pumping) when the pressure ratio meets a certain
value or when the suction pressure is as high as 20
psig. (Compressor suction pressures should never be
allowed to go into a vacuum. Prolonged operation at
low suction pressures will result in overheating of the
scrolls and permanent damage to the scroll tips, drive
bearings and internal seals).
Once the compressor can not pump down to a lower
pressure due to one of the above system conditions, shut
off the suction valve. Turn OFF the main power to unit and
use a recovery machine to recover any refrigerant left in
the indoor coil and line set.
Perform the following task:
1. Start the existing HCFC−22 system in the cooling
mode and close the liquid line valve.
2. Pump as much of the existing HCFC−22 refrigerant
with the compressor back into the outdoor unit until
you have reached the limitations of the outdoor
system. Turn the outdoor unit main power OFF and
use a recovery machine to remove the remaining
refrigerant in the system.
NOTE − It may be necessary to bypass the low pressure
switches if equipped to ensure complete refrigerant
evacuation.
3. When the low side system pressures reach 0 psig,
close the suction line valve.
4. Check gauges after shutdown to confirm that the
valves are not allowing refrigerant to flow back into the
low side of the system.
Removing Existing Outdoor Unit
Perform the following task at the existing outdoor unit:
Disconnect line set at the service valves.
Disconnect electrical service at the disconnect switch.
Remove old outdoor unit.
Page 5
AC13 SERIES
Page 6
Positioning New Outdoor Unit
CAUTION
In order to avoid injury, take proper precaution when
lifting heavy objects.
See Unit Dimensions on page 2 for sizing mounting slab,
platforms or supports. Refer to figure 7 for mandatory
installation clearance requirements.
*
*
* SEE NOTES BELOW THIS FIGURE FOR FURTHER DETAILS.
Figure 7. Installation Clearances
*
*
Some localities are adopting sound ordinances based on
the unit’s sound level registered from the adjacent
property, not from the installation property. Install the unit
as far as possible from the property line. When possible,
do not install the unit directly outside a window. Glass has a
very high level of sound transmission. For proper
placement of unit in relation to a window see the provided
illustration in figure 8.
PLACING UNIT ON SLAB
When installing unit at grade level, the top of the slab
should be high enough above grade so that water from
higher ground will not collect around the unit. The slab
should have a slope tolerance as described in figure 9.
INSTALL UNIT LEVEL OR, IF ON A SLOPE, MAINTAIN SLOPE
TOLERANCE OF 2 DEGREES (OR 2 INCHES PER 5 FEET
[50 MM PER 1.5 M]) AWAY FROM BUILDING STRUCTURE.
BUILDING
STRUCTURE
MOUNTING
SLAB
NOTES:
Service clearance of 30 in. (762 mm) must be
maintained on one of the sides adjacent to the control
box.
Clearance to one of the other three sides must be 36
in. (914 mm)
Clearance to one of the remaining two sides may be
12 in. (305 mm) and the final side may be 6 in. (152
mm)
48 in. (1219 mm) clearance required on top of unit.
A clearance of 24 in. (610 mm) must be maintained
between two units
POSITIONING CONSIDERATIONS
INSTALL UNIT AWAY
FROM WINDOWS
GROUND LEVEL
Figure 9. Slab Mounting at Ground Level
NOTE − If necessary for stability, anchor unit to slab as
described in Stabilizing Unit on Uneven Surfaces on page.
ELEVATING THE UNIT (SMALL−BASE UNITS)
If additional elevation is necessary, raise the unit by
extending the length of the unit support feet. This may be
done by cutting four equal true−cut lengths of Schedule
(SCH) 40, 4" (101.6mm) piping to the height required as
illustrated in figure 10.
BASE
TWO 90° ELBOWS
INSTALLED IN LINE SET
WILL REDUCE LINE SET
VIBRATION.
Figure 8. Outside Unit Placement
506109−01 10/08
LEG DETAIL
4" (101.6MM)
SCH 40 PIPING
Figure 10. Elevated Slab Mounting using Feet
Extenders (Small Base Units)
Page 6
Page 7
NOTE − Keep the height of extenders short enough to
ensure a sturdy installation. If it is necessary to extend
further, consider a different type of field−fabricated
framework that is sturdy enough for greater heights.
The inside diameter of the 4" (101.6mm) piping is
approximately 0.25" (6.35mm) greater than the
pre−installed feet on the unit. Devise a shim that will take up
the space and hold the extenders onto the feet during this
procedure. Small strips of 0.125" (3.175mm) thick
adhesive foam may be used. One or two small 1"
(25.4mm) square strips should be adequate to hold the
extender in place.
ELEVATING THE UNIT (LARGER−BASE UNITS)
Unlike the small−base units which use round support feet,
the larger−base units are outfitted with elongated support
feet as illustrated in figure 11 which uses a similar method
for elevating the unit.
If additional elevation is necessary, raise the unit by
extending the length of the unit support feet. This may be
achieved by using a 2" SCH 40 female threaded adapter.
The specified coupling will fit snuggly into the recessed
portion of the feet. Use additional 2" SCH 40 male threaded
adaptors which can be threaded to the female threaded
adaptors to make additional adjustments to the level of the
unit.
BASE
Removing and Installing Panels
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.
REMOVING PANELS
Remove the louvered panels as follows:
1. Remove two screws, allowing the panel to swing open
slightly as illustrated in figure 12.
NOTE − Hold the panel firmly throughout this procedure
2. Rotate bottom corner of panel away from hinge corner
post until lower three tabs clear the slots as illustrated
in figure 12, detail B.
3. Move panel down until lip of upper tab clears the top
slot in corner post as illustrated in figure 12, detail A.
PANEL SHOWN SLIGHTLY
ROTATED TO ALLOW TOP
TAB TO EXIT (OR ENTER) TOP
SLOT FOR REMOVING (OR
INSTALLING) PANEL.
LIP
SCREW
HOLES
LEG DETAIL
2" (50.8MM) SCH 40
FEMALE THREADED
ADAPTER
Figure 11. Elevated Slab Mounting using Feet
Extenders (Larger Base Units)
ROOF MOUNTING
Install unit at a minimum of four inches above the surface
of the roof. Care must be taken to ensure weight of unit is
properly distributed over roof joists and rafters. Either
redwood or steel supports are recommended.
Page 7
DETAIL A
DETAIL B
ROTATE IN THIS DIRECTION;
Detail C
THEN DOWN TO REMOVE
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
Figure 12. Removing/Installing Louvered Panels
(Details A, B and C)
AC13 SERIES
Page 8
HOLD DOOR FIRMLY TO THE HINGED
SIDE TO MAINTAIN FULLY−ENGAGED
ANGLE MAY BE TOO
EXTREME
PREFERRED ANGLE
FOR INSTALLATION
MAINTAIN MINIMUM
PANEL ANGLE (AS
CLOSE TO PARALLEL
WITH THE UNIT AS
POSSIBLE) WHILE
INSTALLING PANEL.
TABS
Figure 13. Removing/Installing Louvered Panels
(Detail D)
INSTALLING PANEL
Install the louvered panels as follows:
1. Position the panel almost parallel with the unit as
illustrated in figure 13, detail D with the screw side as
close to the unit as possible.
2. With a continuous motion slightly rotate and guide the
lip of top tab inward as illustrated in figure 12, details
A and C; then upward into the top slot of the hinge
corner post.
3. Rotate panel to vertical to fully engage all tabs.
4. Holding the panel’s hinged side firmly in place, close
the right−hand side of the panel, aligning the screw
holes.
5. When panel is correctly positioned and aligned, insert
the screws and tighten.
STABILIZING UNIT ON UNEVEN SURFACES
To help stabilize an outdoor unit, some installations may
require strapping the unit to the pad using brackets and
anchors commonly available in the marketplace.
With unit positioned at installation site, remove two side
louvered panels to expose the unit base pan.Install the
brackets as illustrated in figure 14 using conventional
practices; replace the panels after installation is complete.
IMPORTANT
Unit Stabilizer Bracket Use (field−provided):
Always use stabilizers when unit is raised above the
factory height. (Elevated units could become unstable in gusty wind conditions).
Stabilizers may be used on factory height units
when mounted on unstable an uneven surface.
Slab Side Mounting
#10 1/2" LONG SELF−
DRILLING SHEET
METAL SCREWS
STABILIZING
BRACKET (18 GAUGE
METAL − 2" WIDTH;
HEIGHT AS REQ’D)
#10 1−1/4" LONG
HEX HD SCREW
AND FLATWASHER
CONCRETE SLAB − USE PLASTIC
PLASTIC ANCHOR (HOLE DRILL
1/4")PLASTIC SLAB − NO PLASTIC
ANCHOR (HOLE DRILL 1/8")
COIL
BASE PAN
CORNER POST
Deck Top
Mounting
STABILIZING BRACKET
(18 GAUGE METAL − 2"
WIDTH; HEIGHT AS
REQ’D); BEND TO FORM
RIGHT ANGLE
FOR EXTRA
ONE BRACKET PER SIDE (MIN.); FOR EXTRA STABILITY,
2 BRACKETS PER SIDE, 2" FROM EACH CORNER.
STABILITY
MINIMUM 1
PER SIDE
Figure 14. Installing Stabilizer Brackets
New or Replacement Line Set
This section provides information on installation or
replacement of existing line set. If line set is not being
installed then proceed to Brazing Connections on page 10.
If refrigerant lines are routed through a wall, seal and
isolate the opening so vibration is not transmitted to the
building. Pay close attention to line set isolation during
installation of any HVAC system. When properly isolated
from building structures (walls, ceilings. floors), the
refrigerant lines will not create unnecessary vibration and
subsequent sounds. Also, consider the following when
placing and installing a high−efficiency air conditioner.
REFRIGERANT LINE SET
Field refrigerant piping consists of liquid and suction lines
from the outdoor unit (braze connections) to the indoor unit
coil (flare or sweat connections). Use Lennox L15 (sweat,
non−flare) series line set, or use field−fabricated refrigerant
lines as listed in table 2.
NOTE − When installing refrigerant lines longer than 50
feet, see the Lennox Refrigerant Piping Design and
Fabrication Guidelines, or contact Lennox Technical
Support Product Applications for assistance. To obtain the
correct information from Lennox, be sure to communicate
the following points:
506109−01 10/08
Page 8
Page 9
SModel (AC13) and size (e.g. −060) of unit.
SLine set diameters for the unit being installed (from
table 2 and total length of installation.
Number of elbows and if there is a rise or drop of the
piping.
Table 2. Refrigerant Line Set
TO HANG LINE SET FROM JOIST OR
RAFTER, USE EITHER METAL STRAPPING
MATERIAL OR ANCHORED HEAVY NYLON
WIRE TIES.
STRAPPING MATERIAL
(AROUND SUCTION
LINE ONLY)
8 FEET
FLOOR JOIST OR
ROOF RAFTER
8 FEET
WIRE TIE
(AROUND
SUCTION LINE
ONLY)
TAPE OR
WIRE TIE
AC13
−018
−024
−030
−036
−042
−048
−060
Valve Field
Connections
Liquid
Line
3/8" (10
mm)
3/8" (10
mm)
3/8" (10
mm)
Suction
Line
3/4" (19
mm)
7/8" (22
mm)
1−1/8"
(29 mm)
Recommended Line Set
Liquid
Line
3/8" (10
mm)
3/8" (10
mm)
3/8" (10
mm)
Suction
Line
3/4" (19
mm)
7/8 (22
mm)
1−1/8"
(29 mm)
L15 Line
Set
L15−41
15 ft. − 50
ft. (4.6 m
− 15 m)
L15−65
15 ft. − 50
ft. 4.6 m −
15 m)
Field
Fabricated
MATCHING WITH NEW OR EXISTING INDOOR COIL
AND LINE SET
The RFC1−metering line consisted of a small bore copper
line that ran from condenser to evaporator coil. Refrigerant
was metered into the evaporator by utilizing
temperature/pressure evaporation effects on refrigerant in
the small RFC line. The length and bore of the RFC line
corresponded to the size of cooling unit.
If the AC13 is being used with either a new or existing
indoor coil which is equipped with a liquid line which served
as a metering device (RFCI), the liquid line must be
replaced prior to the installation of the AC13 unit. Typically
a liquid line used to meter flow is 1/4" in diameter and
copper.
STRAP THE SUCTION LINE TO
THE JOIST OR RAFTER AT 8 FEET
INTERVALS THEN STRAP THE
LIQUID LINE TO THE SUCTION
LINE.
TAPE OR
WIRE TIE
FLOOR JOIST OR
ROOF RAFTER
METAL
SLEEVE
Figure 15. Refrigerant Line Set: Installing Horizontal
Runs
IMPORTANT - REFRIGERANT LINES
OUTSIDE WALL
WOOD BLOCK
BETWEEN STUDS
NOTE − SIMILAR INSTALLATION
PRACTICES SHOULD BE USED
IF LINE SET IS TO BE INSTALLED
ON EXTERIOR OF OUTSIDE
WALL.
MUST NOT CONTACT WALL.
SUCTION LINE
SLEEVE
LIQUID LINE
WIRE TIE
INSIDE WALL
STRAP
SLEEVE
WIRE TIE
WOOD BLOCK
WIRE TIE
STRAP
INSTALLING LINE SET
Line Set IsolationThis reference illustrates
procedures, which ensure proper refrigerant line set
isolation:
Installation of line set on horizontal runs is
illustrated in figure 15.
Installation of line set on vertical runs is illustrated in
figure 16.
Installation of a transition from horizontal to
vertical is illustrated in figure 17.
Page 9
SUCTION LINE WRAPPED
WITH ARMAFLEX
LIQUID LINE
OUTSIDE
PVC
PIPE
WALL
FIBERGLASS
INSULATION
CAULK
IMPORTANT! REFRIGERANT
LINES MUST NOT CONTACT
STRUCTURE.
Figure 16. Refrigerant Line Set: Installing Vertical
Runs (New Construction Shown)
AC13 SERIES
Page 10
ANCHORED HEAVY
NYLON WIRE TIE
WALL
STUD
STRAP LIQUID LINE
TO SUCTION LINE
AUTOMOTIVE
MUFFLER-TYPE HANGER
WALL
STUD
STRAP LIQUID LINE TO
SUCTION LINE
METAL SLEEVE
CUT AND DEBUR
7
INSTALL CORE ONLY FOR
BOTH SERVICE PORTS AFTER
THEY HAVE COOLED.
LIQUID LINE
SUCTION LINE − WRAPPED IN
ARMAFLEX
METAL
SLEEVE
SUCTION LINE − WRAPPED IN ARMAFLEX
Figure 17. Refrigerant Line Set: Transition from Vertical to Horizontal
1
INDOOR UNIT
6
BRAZE LINE SET
2
REMOVE CAP AND CORE FROM
BOTH LIQUID AND SUCTION
SERVICE PORTS
SERVICE PORT MUST BE
OPEN TO ALLOW EXIT
POINT FOR NITROGEN
SUCTION LINE
LIQUID LINE
5
3
ATTACH
GAUGES
SERVICE
VALVE
SERVICE
VALVE
OUTDOOR
UNIT
FLOW NITROGEN
NITROGEN
LIQUID LINE
4
WRAP
SERVICE
VALV E
Figure 18. Brazing Connections
Brazing Connections
Use the following procedure to braze the line set to the new
air conditioner unit. Figure 18 is provided as a general
guide for preparing to braze the line set to the air
conditioner unit.
CAUTION
Brazing alloys and flux contain materials which are
hazardous to your health.
Avoid breathing vapors or fumes from brazing
operations. Perform operations only in well
ventilated areas.
Wear gloves and protective goggles or face shield
to protect against burns.
Wash hands with soap and water after handling
brazing alloys and flux.
506109−01 10/08
WARNING
Danger of fire. Bleeding the
refrigerant charge from only the high
side may result in the low side shell
and suction tubing being
pressurized. Application of a brazing
torch while pressurized may result in
ignition of the refrigerant and oil
mixture − check the high and low
pressures before un−brazing.
WARNING
When using a high pressure gas such
as dry nitrogen to pressurize a
refrigeration or air conditioning
system, use a regulator that can
control the pressure down to 1 or 2
psig (6.9 to 13.8 kPa).
Page 10
Page 11
1. Cut ends of the refrigerant lines square (free from
nicks or dents). Debur the ends. The pipe must remain
round, do not pinch end of the line.
2. Remove service cap and core from both the suction
and liquid line service ports.
3. Connect gauge low pressure side to liquid line service
valve.
4. To protect components during brazing, wrap a wet
cloth around the liquid line service valve body and
copper tube stub and use another wet cloth
underneath the valve body to protect the base paint.
5. Flow regulated nitrogen (at 1 to 2 psig) through the
refrigeration gauge set into the valve stem port
connection on the liquid line service valve and out of
the valve stem port connection on the suction service
valve. The TXV metering device at the indoor unit coil
will allow low pressure
nitrogen to flow through the
system.)
NOTE − The fixed orifice or TXV metering device at the
indoor unit will allow low pressure nitrogen to flow through
the system.)
NOTE − Use silver alloy brazing rods with five or six percent
minimum silver alloy for copper−to−copper brazing or 45
percent silver alloy for copper−to−brass or copper−to−steel
brazing.
6. Braze the liquid line to the liquid line service valve.
Turn off nitrogen flow.
IMPORTANT
Repeat procedure starting at paragraph 4 for brazing the
suction line to service port valve.
7. After all connections have been brazed, disconnect
manifold gauge set the from service ports and remove
wrapping. Reinstall the service port core for both of the
outdoor unit’s service valves.
Removing Indoor Unit Metering Device
Remove the existing HCFC−22 refrigerant flow control
orifice or thermal expansion valve from the indoor coil.
REPLACEMENT PARTS
If replacement parts are necessary for the indoor unit,
order kit 69J46 (LB−95325A). The kit includes the
following:
LIQUID LINE ORIFICE HOUSINGS (10)
TEFLON RINGS (20)
LIQUID LINE ASSEMBLIES
(INCLUDES STRAINER) (10)
BRASS NUTS (10)
Figure 19. 69J46 Kit Components
LIQUID LINE
ASSEMBLY
PISTON
RETAINER
STRAINER
COPPER
TUBE
TYPICAL FIXED ORIFICE REMOVAL PROCEDURE
DISTRIBUTOR TUBES
LIQUID LINE ORIFICE HOUSING
DISTRIBUTOR
ASSEMBLY
VALVE STEM
TEFLON RING
FIXED
ORIFICE
VALVE STEM CAP
REMOVE AND DISCARD
VALVE STEM ASSEMBLY
(IF PRESENT)
BRASS NUT
LIQUID LINE ASSEMBLY
(INCLUDES STRAINER)
(Uncased Coil Shown)
Figure 20. Typical Fixed Orifice Removal
1. On fully cased coils, remove the coil access and
plumbing panels.
2. Remove any shipping clamps holding the liquid line
and distributor assembly.
3. Using two wrenches, disconnect liquid line from liquid
line orifice housing. Take care not to twist or damage
distributor tubes during this process.
4. Remove and discard fixed orifice, valve stem
assembly if present and Teflon ring as illustrated in
figure 20.
5. Use a field−provided fitting to temporary reconnect the
liquid line to the indoor unit’s liquid line orifice housing.
TYPICAL TXV REMOVAL PROCEDURE
(Uncased Coil Shown)
TWO PIECE
PATCH PLATE
(UNCASED COIL
ONLY)
DISTRIBUTOR
TUBES
DISTRIBUTOR
ASSEMBLY
MALE EQUALIZER
LINE FITTING
LIQUID LINE
ORIFICE HOUSING
EQUALIZER
LINE
SENSING
BULB
STUB END
TXV
TEFLON
RING
LIQUID LINE ASSEMBLY
WITH BRASS NUT
SUCTION
LINE
TEFLON
RING
SENSING
LINE
LIQUID
LINE
Figure 21. Typical TXV Removal
Page 11
AC13 SERIES
Page 12
1. On fully cased coils, remove the coil access and
plumbing panels.
2. Remove any shipping clamps holding the liquid line
and distributor assembly.
3. Disconnect the equalizer line from the TXV equalizer
line fitting on the suction line.
4. Remove the suction line sensing bulb as illustrated in
figure 21.
5. Remove the liquid line from the TXV at the liquid line
assembly.
6. Disconnect the TXV from the liquid line orifice housing.
Take care not to twist or damage distributor tubes
during this process.
7. Remove and discard TXV and the two Teflon rings as
illustrated in figure 21.
8. Use a field−provided fitting to temporary reconnect the
liquid line to the indoor unit’s distributor assembly.
Installing New Indoor Metering Device
AC13 units can be configured for use in with HCFC−22
fixed orifice or TXV metering devices. This section
provides instructions on installing either a fixed orifice, or
TXV refrigerant metering device.
FIXED ORIFICE (1)
FIXED ORIFICE EXTRACTOR (1)
TEFLON RING (1)
FIXED ORIFICE STICKER (1)
Figure 23. Fixed Orifice Kit Components
TXV (1)
HEX HEAD BOLTS
AND NUTS (2)
TEFLON
RINGS (2)
COPPER
MOUNTING
STRAP (1)
9
10
8
11
1/8 TURN
12
1
2
3
10
9
4
7
5
6
12
11
8
7
6
1/2 TURN
1
2
3
4
5
Figure 22. Tightening Distance
AC13 ENGINEERING HANDBOOK
See the AC13 Engineering Handbook for approved
indoor/outdoor match−ups, applicable fixed orifice and
TXV kits, and application information.
Figures 23 and 24 illustrates the typical RFC and TXV kit
parts and quantities.
Figure 24. TXV Kit Components
TYPICAL FIXED ORIFICE INSTALLATION
PROCEDURE
Use figure 25 to assist in the installation procedure.
1. Remove the field−provided fitting that temporary
reconnected the liquid line to the indoor unit’s liquid
line orifice housing.
2. Ensure that the fixed orifice supplied with the outdoor
unit is installed with the nylon seat pointing toward the
liquid line orifice housing.
3. Apply a small amount of refrigerant oil on the Teflon
washer and insert the Teflon ring securely into the
orifice housing.
4. Attached the liquid line assembly to the liquid line
orifice housing. Finger tighten and use an appropriately
sized wrench to turn an additional 1/2 turn clockwise
as illustrated in figure 22, or 20 ft−lb.
5. Place the supplied fixed orifice sticker on the indoor
cabinet after installation.
506109−01 10/08
Page 12
Page 13
LIQUID LINE
ORIFICE HOUSING
FIXED
ORIFICE
LIQUID LINE ASSEMBLY
WITH BRASS NUT
TEFLON
WASHER
LIQUID
LINE
(Uncased Coil Shown)
Figure 25. Typical Fixed Orifice Installation
TYPICAL TXV INSTALLATION PROCEDURE
The TXV unit can be installed internal or external to the
indoor coil. In applications where an uncased coil is being
installed in a field−provided plenum, install the TXV in a
manner that will provide access for field servicing of the
TXV. Refer to Figure 26 for reference during installation of
TXV unit.
TWO PIECE
PATCH PLATE
(UNCASED COIL
ONLY)
DISTRIBUTOR
TUBES
(Uncased Coil Shown)
LIQUID LINE
ORIFICE
HOUSING
STUB END
TXV
TEFLON
RING
1. Remove the field−provided fitting that temporary
reconnected the liquid line to the indoor unit’s
distributor assembly.
2. Install one of the provided Teflon rings around the
stubbed end of the TXV and lightly lubricate the
connector threads and expose surface of the Teflon
ring with refrigerant oil.
3. Attach the stubbed end of the kit valve to the liquid line
assembly. Finger tighten and use an appropriately
sized wrench to turn an additional 1/2 turn clockwise
as illustrated in figure 22, or 20 ft−lb.
4. Place the remaining Teflon ring around the other end
of the TXV. Lightly lubricate connector threads and
expose surface of the Teflon ring with refrigerant oil.
5. Attach the liquid line to the TXV. Finger tighten and use
an appropriately sized wrench to turn an additional 1/2
turn clockwise as illustrated in figure 22, or 20 ft−lb.
6. Attach the suction line sensing bulb in the proper
orientation as illustrated in figure 27 using the clamp
and screws provided.
NOTE − Insulating the sensing bulb once installed may be
required when the bulb location is external to the coil
casing.
SUCTION LINE
BULB
12
ON LINES SMALLER THAN
7/8", MOUNT SENSING BULB
AT EITHER THE 3 OR 9
O’CLOCK POSITION.
BULB
TEFLON
DISTRIBUTOR
ASSEMBLY
MALE EQUALIZER LINE
FITTING (SEE FIGURE 28
FOR FURTHER DETAILS)
SENSING BULB INSULATION IS
REQUIRED IF MOUNTED EXTERNAL
TO THE COIL CASING. SEE FIGURE 27
FOR BULB POSITIONING.
EQUALIZER
LINE
RING
LIQUID LINE ASSEMBLY
WITH BRASS NUT
SUCTION
LINE
SENSING
LINE
LIQUID
LINE
Figure 26. Typical TXV Installation
To prevent any possibility of water damage, properly
insulate all parts of the TXV assembly that may sweat due
to temperature differences between the valve and its
surrounding ambient temperatures.
SUCTION LINE
12
BULB
ON 7/8" AND LARGER LINES,
MOUNT SENSING BULB AT
EITHER THE 4 OR 8 O’CLOCK
POSITION. NEVER MOUNT
ON BOTTOM OF LINE.
BULB
NOTE − Never mount on bottom of line.
Figure 27. TXV Sensing Bulb Installation
7. Remove and discard either the flare seal cap or flare
nut with copper flare seal bonnet from the equalizer
line port on the suction line as illustrated in figure 28.
IMPORTANT
When removing the flare nut, ensure that the copper
flare seal bonnet is removed.
Page 13
AC13 SERIES
Page 14
FLARE SEAL
CAP
OR
MALE BRASS EQUALIZER
Figure 28. Copper Flare Seal Bonnet Removal
8. Connect the equalizer line from the TXV to the
equalizer suction port on the suction line. Finger
tighten the flare nut plus 1/8 turn (7 ft−lbs) as illustrated
in figure 22.
FLARE NUT
COPPER
FLARE SEAL
BONNET
LINE FITTING
SUCTION LINE
Testing for Leaks
After the line set has been connected to the indoor unit and
air conditioner, check the line set connections and indoor
unit for leaks. Use the following procedure to test for leaks:
IMPORTANT
Leak detector must be capable of sensing HFC
refrigerant.
WARNING
Refrigerant can be harmful if it is inhaled.
Refrigerant must be used and recovered
responsibly.
Failure to follow this warning may result in personal
injury or death.
WARNING
Fire, Explosion and Personal Safety
Hazard.
Failure to follow this warning could
result in damage, personal injury or
death.
Never use oxygen to pressurize or
purge refrigeration lines. Oxygen,
when exposed to a spark or open
flame, can cause damage by fire and/
or an explosion, that could result in
personal injury or death.
1. Connect an HCFC−22 manifold gauge set high
pressure hose to the suction valve service port.
(Normally, the high pressure hose is connected to the
liquid line port; however, connecting it to the suction
port better protects the manifold gauge set from high
pressure damage.)
506109−01 10/08
NOTE − Normally, the high pressure hose is connected to
the liquid line port; however, connecting it to the suction
port better protects the manifold gauge set from high
pressure damage.
2. With both manifold valves closed, connect the cylinder
of HCFC−22 refrigerant to the center port of the
manifold gauge set. Open the valve on the HCFC−22
cylinder (suction only).
3. Open the high pressure side of the manifold to allow
HCFC−22 into the line set and indoor unit. Weigh in a
trace amount of HCFC−22. [A trace amount is a
maximum of two ounces (57 g) refrigerant or three
pounds (31 kPa) pressure]. Close the valve on the
HCFC−22 cylinder and the valve on the high pressure
side of the manifold gauge set. Disconnect the
HCFC−22 cylinder.
4. Connect a cylinder of dry nitrogen with a pressure
regulating valve to the center port of the manifold
gauge set.
5. Adjust dry nitrogen pressure to 150 psig (1034 kPa).
Open the valve on the high side of the manifold gauge
set in order to pressurize the line set and the indoor unit.
6. After a few minutes, open one of the service valve
ports and verify that the refrigerant added to the
system earlier is measurable with a leak detector.
NOTE − Amounts of refrigerant will vary with line lengths.
7. Check all joints for leaks.
8. Purge dry nitrogen and HCFC−22 mixture.
9. Correct any leaks and recheck.
10. After leak testing disconnect gauges from service
ports.
Evacuating the System
WARNING
Danger of Equipment Damage. Avoid deep
vacuum operation. Do not use compressors to
evacuate a system. Extremely low vacuums can
cause internal arcing and compressor failure.
Damage caused by deep vacuum operation will
void warranty.
IMPORTANT
Use a thermocouple or thermistor electronic
vacuum gauge that is calibrated in microns. Use an
instrument capable of accurately measuring down
to 50 microns.
Evacuating the system of non−condensables is critical for
proper operation of the unit. Non−condensables are
defined as any gas that will not condense under
temperatures and pressures present during operation of
an air conditioning system. Non−condensables and water
suction combine with refrigerant to produce substances
that corrode copper piping and compressor parts.
1. Connect manifold gauge set to the service valve ports
as follows:
low pressure gauge to suction line service valve
Page 14
Page 15
high pressure gauge to liquid line service valve
2. Connect micron gauge.
3. Connect the vacuum pump (with vacuum gauge) to
the center port of the manifold gauge set.
4. Open both manifold valves and start the vacuum
pump.
5. Evacuate the line set and indoor unit to an absolutepressure of 23,000 microns (29.01 inches of
mercury).
NOTE − During the early stages of evacuation, it is
desirable to close the manifold gauge valve at least once to
determine if there is a rapid rise in sure indicates a
relatively large leak. If this occurs, repeat the leak testingprocedure.
NOTE − The term absolute pressure means the total
actual pressure within a given volume or system, above
the absolute zero of pressure. Absolute pressure in a
vacuum is equal to atmospheric pressure minus vacuum
pressure.
6. When the absolute pressure reaches 23,000 microns
(29.01 inches of mercury), close the manifold gauge
valves, turn off the vacuum pump and disconnect the
manifold gauge center port hose from vacuum pump.
Attach the manifold center port hose to a dry nitrogen
cylinder with pressure regulator set to 150 psig (1034
kPa) and purge the hose. Open the manifold gauge
valves to break the vacuum in the line set and indoor
unit. Close the manifold gauge valves.
7. Shut off the dry nitrogen cylinder and remove the
manifold gauge hose from the cylinder. Open the
manifold gauge valves to release the dry nitrogen from
the line set and indoor unit.
8. Reconnect the manifold gauge to the vacuum pump,
turn the pump on, and continue to evacuate the line set
and indoor unit until the absolute pressure does not
rise above 500 microns (29.9 inches of mercury) within
a 20−minute period after shutting off the vacuum pump
and closing the manifold gauge valves.
9. When the absolute pressure requirement above has
been met, disconnect the manifold hose from the
vacuum pump and connect it to an upright cylinder of
HCFC−22 refrigerant. Open the manifold gauge valve
1 to 2 psig in order to release the vacuum in the line set
and indoor unit.
10. Close manifold gauge valves and shut off the
HCFC−22 cylinder and remove the manifold gauge
set.
2. Evacuate the system to remove as much of the
moisture as possible.
3. Use nitrogen to break the vacuum and install a liquid
line filter drier in the system.
4. Evacuate the system again. Then, weigh the
appropriate amount of HCFC−22 refrigerant as listed
on unit nameplate into the system.
5. Monitor the system to determine the amount of
moisture remaining in the oil. It may be necessary to
replace the filter drier several times to achieve the
required dryness level. If system dryness is not
verified, the compressor will fail in the future.
Electrical Connections
In the U.S.A., wiring must conform with current local codes
and the current National Electric Code (NEC). In Canada,
wiring must conform with current local codes and the current
Canadian Electrical Code (CEC).
Refer to the furnace or blower coil installation instructions
for additional wiring application diagrams and refer to unit
nameplate for minimum circuit ampacity and maximum
over−current protection size.
NOTE − To facilitate conduit, a hole is in the bottom of the
control box. Connect conduit to the control box using a
proper conduit fitting.
NOTE − Units are approved for use only with copper
conductors.
NOTE − 24V, Class II circuit connections are made in the
low voltage junction box. See figure 30 for field wiring
diagram.
NOTE − For proper voltages, select thermostat wire gauge
per the following chart:
Table 3. Wire Run Lengths
Wire run lengthAWG #Insulation type
less than 100’ (30m)18
more than 100’ (30m)16
WIRE TIES
color−coded, temperature
rating 35ºC minimum
HIGH VOLTAGE
FIELD WIRING
LOW VOLTAGE
FIELD WIRING
FACTORY
WIRING
Servicing Unit Delivered Void of Charge
If the system is void of refrigerant, clean the system using
the procedure described below.
1. Use nitrogen to pressurize the system and check for
leaks. Repair all leaks.
GROMMET
Figure 29. Separating High/Low Voltage Field Wiring
Page 15
AC13 SERIES
Page 16
NOTE − A COMPLETE UNIT WIRING DIAGRAM IS LOCATED
INSIDE THE UNIT CONTROL BOX COVER.
Figure 30. Typical Wiring Diagram
THERMOSTATINDOOR UNIT
W1
POWER
R
HEAT
COOLING
Y
INDOOR
BLOWER
G
COMMON
C
R
W
Y
G
C
OUTDOOR
UNIT
Y1
C
Figure 31. Typical Field Low Voltage Wiring
1. Install line voltage power supply to unit from a properly
sized disconnect switch. Any excess high voltage field
wiring should be trimmed or secured away from the
low voltage field wiring.
2. Ground unit at unit disconnect switch or to an earth
ground.
3. Install room thermostat (ordered separately) on an
inside wall approximately in the center of the
conditioned area and 5 feet (1.5m) from the floor. It
should not be installed on an outside wall or where it
can be effected by sunlight, drafts or vibrations.
4. Install low voltage wiring from outdoor to indoor unit
and from thermostat to indoor unit as illustrated in
figure 31.
5. Do not bundle any excess 24V control wire inside
control box. Run control wire through installed wire tie
and tighten wire tie to provide low voltage strain relief
and to maintain separation of field installed low and
high voltage circuits.
Start−Up and Charging Procedures
IMPORTANT
If unit is equipped with a crankcase heater, it should
be energized 24 hours before unit start−up to
prevent compressor damage as a result of slugging.
1. Rotate fan to check for frozen bearings or binding.
2. Inspect all factory− and field−installed wiring for loose
connections.
3. After evacuation is complete, open the liquid line and
suction line service valves to release the refrigerant
charge (contained in outdoor unit) into the system.
4. Replace the stem caps and secure finger tight, then
tighten an additional one-sixth (1/6) of a turn.
5. Check voltage supply at the disconnect switch. The
voltage must be within the range listed on the unit’s
nameplate. If not, do not start the equipment until you
have consulted the power company and the voltage
condition has been corrected.
6. Set the thermostat for a cooling demand. Turn on
power to the indoor blower and close the outdoor unit
disconnect switch to start the unit.
7. Recheck voltage while the unit is running. Power must
be within range shown on the nameplate.
8. Check system for sufficient refrigerate by using the
procedures listed under Testing and Charging System
on page 17.
506109−01 10/08
Page 16
Page 17
SETTING UP TO CHECK CHARGE
1. Close manifold gauge set valves. Connect the center
manifold hose to an upright cylinder of HCFC−22.
2. Connect the manifold gauge set to the unit’s service
ports as illustrated in figure 3.
low pressure gauge to suction service port
high pressure gauge to liquid service port
INDOOR AIRFLOW CHECK
Check indoor airflow using the Delta−T (
DT) process using
the illustration in figure 32.
DETERMINING CHARGE METHOD
Use the illustration in figure 33 to determine the correct
charging method.
Figure 32. Checking Indoor Airflow over Evaporator Coil using Delta−T Chart
START: Determine how refrigerant is metered
WHEN TO CHARGE?
Warm weather best
Can charge in colder weather
CHARGE METHOD? Determine by:
Metering device type
Outdoor ambient temperature
REQUIREMENTS:
Sufficient heat load in structure
Indoor temperature between 70-80ºF
(21−26ºC)
(18.3ºC) and
Above
Manifold gauge set connected to unit
Thermometers:
− to measure outdoor ambient
temperature
− to measure liquid line temperature
− to measure suction line
temperature
APPROACH OR
SUBCOOLING
Figure 33. Determining Charge Method
BULB
65ºF
WET
TXV
A
72º
DRY
BULB
1. Determine the desired DTMeasure entering air temperature
using dry bulb (A) and wet bulb (B). DT is the intersecting value of A
and B in the table (see triangle).
2. Find temperature drop across coilMeasure the coil’s dry bulb
entering and leaving air temperatures (A and C). Temperature Drop
Formula: (T
3. Determine if fan needs adjustmentIf the difference between the
measured T
justment is needed. See examples: Assume DT = 15 and A temp. =
72º, these C temperatures would necessitate stated actions:
Cº T
Drop
53º 19–15 =4 Increase the airflow
58º14–15=−1 (within +3º range) no change
62º10–15=−5 Decrease the airflow
4. Adjust the fan speedSee indoor unit instructions to in-
crease/decrease fan speed.
Changing air flow affects all temperatures; recheck temperatures to
confirm that the temperature drop and DT are within +3º.
) = A minus C.
Drop
and the desired DT (T
Drop
–DT=ºF ACTION
Which
–DT) is within +3º, no ad-
Drop
RFC
metering
device?
64ºF
(17.7ºC) and
Below
WEIGH-IN
40ºF
(4.4ºC) and
Above
39ºF
(3.8ºC) and
Below
WEIGH-INSUPERHEAT
Page 17
AC13 SERIES
Page 18
START: Measure outdoor ambient temperature
USE EITHER APPROACH
OR SUBCOOLING
METHOD
65ºF
(18ºC) and
ABOVE
WEIGH IN TXV
Refrigerant Charge per Line Set Length
Liquid Line
Set Diameter
3/8" (9.5 mm)
NOTE − *If line length is greater than 15 ft. (4.6 m), add this
amount. If line length is less than 15 ft. (4.6 m), subtract this
amount.
Ounces per 5 feet (g per 1.5 m)
adjust from 15 feet (4.6 m) line set*
3 ounce per 5’ (85 g per 1.5 m)
Figure 34. HCFC−22 Weigh In TXV Method
(17.7ºC) and
BELOW
ABOVE or
BELOW
64ºF
1. Check Liquid and suction line pressures
2. Compare unit pressures with Table 5,
Normal Operating Pressures.
3. Conduct leak check; evacuate as
previously outlined.
4. Weigh in the unit nameplate charge plus
any charge required for line set differences
over 15 feet.
This nameplate is for illustration purposes
only. Go to actual nameplate on outdoor
unit for charge information.
START: Measure outdoor ambient temperature
USE WEIGH-IN METHOD
DO NOT CHARGE UNIT
Weigh-in or remove refrigerant
(Results of charging at low
based upon line length
temperatures not reliable)
64ºF
ABOVE or
BELOW
(17.7ºC) and
BELOW
BLOCK OUTDOOR COIL: [sometimes necessary with lower
temperatures] Use cardboard or plastic sheet to restrict the airflow
through the outdoor coil to achieve pressures from 200−250 psig
(1379−1724 kPa) .Higher pressures are needed to check charge.
Block equal sections of air intake panels and move coverings
sideways until the liquid pressure is in the above noted ranges.
If refrigerant is added
or removed, verify
charge using the
Approach Method.
If value is LESS
than shown, add
refrigerant.
If value is MORE
than shown, remove
refrigerant.
MORE or
LESS
65ºF
(18ºC)
and
ABOVE
1. Confirm proper airflow across coil using figure
32.
2. Compare unit pressures with Table 5, NormalOperating Pressures.
3. Set thermostat to call for heat (must have a
cooling load between 70-80ºF (21−26ºC)
4. Connect gauge set
5. Measure outdoor ambient temperature
6. When heat demand is satisfied, set thermostat to
call for cooling
7. Allow temperatures and pressures to stabilize.
NOTE − If necessary, block outdoor coil to
maintain 325 − 375 psig.
8. Record liquid line temperature:
LIQº = ______
9. Measure liquid line pressure and use the value to
determine saturation temperature (see table 4):
SATº = ______
10. Subtract to determine subcooling (SCº):
SATº_____ − LIQº _____ = SCº _____
11. Compare results with table below.
SCº (Subcooling) Values (F:+/−1.0° [C: +/−0.6°])
−018−024−030−036−042−048−060
TEMP*7 (3.8) 12 (6.7)9 (5.0)10 (5.6) 14(8.0) 10 (5.6) 13 (7.2)
*Temperature of air entering outdoor coil is 65ºF (18ºC) or above.
Figure 35. HCFC−22 Subcooling TXV Charge
506109−01 10/08
Page 18
Page 19
START: Measure outdoor ambient temperature
DO NOT CHARGE UNIT
USE WEIGH-IN METHOD
(Results of charging at low
Weigh-in or remove refriger-
temperatures not reliable)
ant based upon line length
64ºF
(17.7ºC) and
BELOW
If refrigerant is added
or removed, verify
charge using the
Subcooling Method.
If value is LESS
than shown, add
refrigerant.
If value is MORE
than shown, remove
refrigerant.
MORE or
LESS
Figure 36. HCFC−22 Approach TXV Charge
65ºF
(18ºC)
and
ABOVE
ABOVE or
BELOW
1. Confirm proper airflow across coil using figure
32.
2. Compare unit pressures with Table 5, NormalOperating Pressures.
3. Set thermostat to call for heat (must have a
cooling load between 70-80ºF (21−26ºC).
4. Connect gauge set.
5. When heat demand is satisfied, set thermostat
to call for cooling.
6. Allow temperatures and pressures to stabilize.
7. Record outdoor ambient temperature:
AMBº =_________
8. Record liquid line temperature:
LIQº = __________
9. Subtract to determine approach (APPº):
LIQº_____ − AMBº _____ = APPº_____
10. Compare results with table below.
APPº (Approach) Values(F:+/−1.0° [C: +/−0.6°])
−018−024−030−036−042−048−060
TEMP*6 (3.3)6 (3.3)8 (4.4)12 (6.7)5 (2.8)6 (3.3)7 (3.8)
*Temperature of air entering outdoor coil is 65ºF (18ºC) or above.
START: Measure outdoor ambient temperature
USE SUPERHEAT
40ºF (4ºC)
and
ABOVE
WEIGH IN RFC
Refrigerant Charge per Line Set Length
Liquid Line
Set Diameter
3/8" (9.5 mm)
NOTE − *If line length is greater than 15 ft. (4.6 m), add this
amount. If line length is less than 15 ft. (4.6 m), subtract this
amount.
Ounces per 5 feet (g per 1.5 m)
adjust from 15 feet (4.6 m) line set*
3 ounce per 5’ (85 g per 1.5 m)
Figure 37. HCFC−22 Weigh In RFC Method
39ºF (3.8ºC)
and BELOW
ABOVE or
BELOW
1. Check Liquid and suction line pressures
2. Compare unit pressures with Table 5,
Normal Operating Pressures.
3. Conduct leak check; evacuate as
previously outlined.
4. Weigh in the unit nameplate charge plus
any charge required for line set differences
over 15 feet.
This nameplate is for illustration purposes
only. Go to actual nameplate on outdoor unit
for charge information.
Page 19
AC13 SERIES
Page 20
START: Measure outdoor ambient temperature
USE WEIGH-IN METHOD
Weigh-in or remove refrigerant
based upon line length
If refrigerant is
REMOVED, retest to
confirm that unit is
properly charged.
* Dry−bulb temperature (ºF) of entering outdoor ambient air.
39ºF (3.8ºC)
and BELOW
SHº (Superheat) Values (+/−5ºF)
Wet Bulb (air entering indoor coil)
40ºF (4ºC)
ABOVE or
BELOW
and
ABOVE
1. Confirm proper airflow across coil using figure 32.
2. Compare unit pressures with Table 5, NormalOperating Pressures.
3. Use SUPERHEAT to correctly charge unit or to
verify the charge is correct.
4. Set thermostat to call for heat (must have a cooling
load between 70-80ºF (21−26ºC)
5. Connect gauge set.
6. When heat demand is satisfied, set thermostat to
call for cooling.
7. Allow temperatures and pressures to stabilize.
8. Measure the suction line pressure and use the use
value to determine saturation temperature (table
4):
SATº =_________
9. Record suction line temperature:
VAPº =_________
10. Subtract to determine superheat (SHº):
VAPº − _____ SATº ______ = SHº______
11. Record the wet bulb temperature (air entering
indoor coil):
WB =_______
12. Record outdoor ambient temperature.
13. Compare results with table to the left.
NOTE − Do not attempt to charge system where a
dash appears, system could be overcharged.
Superheat is taken at suction line service port.
Suction line superheat must never be less than 5ºF
at the suction line service port.
If value is LESS than
shown, then REMOVE
refrigerant.
MORE or
LESS
If value is MORE
than shown, then
ADD refrigerant.
If refrigerant is
ADDED, retest to
confirm that unit is
properly charged.
Figure 38. HCFC−22 Superheat RFC Method
Table 4. HCFC−22 Temperature (°F) − Pressure (Psig)
Table 5. Normal Operating Pressures (Liquid +10 and Suction +5 psig)
IMPORTANT
Use this table to perform maintenance checks; it is not a procedure for
charging the system. Minor variations in these pressures may be due to
differences in installations. Significant deviations could mean that the system
is not properly charged or that a problem exists with some component in the
system.
*Temperature of the air entering the outside coil.
**Typical pressures; indoor unit match up, indoor air quality equipment, and indoor load causes pressure variance
Disconnect gauge set and re−install both the liquid and
suction service valve caps.
OUTDOOR UNIT
SERVICE VALVE
INSTALL CAPS
Figure 39. Installing Service Valve Port Caps
System Operation
The outdoor unit and indoor blower cycle are on demand
from the room thermostat. When the thermostat blower
switch is in the ON position, the indoor blower operates
continuously.
Maintenance
WARNING
Electric shock hazard. Can cause
injury or death. Before attempting to
perform any service or maintenance,
turn the electrical power to unit OFF at
disconnect switch(es). Unit may have
multiple power supplies.
WARNING
Improper installation, adjustment, alteration,
service or maintenance can cause personal injury,
loss of life, or damage to property.
Installation and service must be performed by a
licensed professional installer (or equivalent) or a
service agency.
At the beginning of each cooling season, the system
should be checked as follows:
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AC13 SERIES
Page 22
1. Clean and inspect the outdoor coil. The coil may be
flushed with a water hose. Ensure the power is turned
off before you clean the coil.
2. Outdoor fan motor is pre−lubricated and sealed. No
further lubrication is needed.
3. Visually inspect connecting lines and coils for
evidence of oil leaks.
4. Check wiring for loose connections.
5. Check for correct voltage at the unit (with the unit
operating).
6. Check amperage draw outdoor fan motor.
UNIT NAMEPLATE: _________ ACTUAL: __________
NOTE − If owner reports insufficient cooling, the unit should
be gauged and refrigerant charge checked.
INDOOR COIL
1. Clean coil, if necessary.
2. Check connecting lines and coils for signs of oil leaks.
3. Check condensate line and clean, if necessary.
INDOOR UNIT
1. Clean or change filters.
2. Adjust blower speed for cooling. Measure the pressure
drop over the coil to determine the correct blower CFM.
Refer to the unit information service manual for pressure
drop tables and procedure.
3. Check blower drive belt for wear and proper tension.
4. Check all wiring for loose connections
5. Check for correct voltage at unit (blower operating).
6. Check amperage draw on blower motor.
UNIT NAMEPLATE: _________ ACTUAL: __________
Homeowner Information
MAINTENANCE
In order to ensure peak performance, your system must be
properly maintained. Clogged filters and blocked airflow
prevent your unit from operating at its most efficient level.
1. Air FilterAsk your Lennox dealer to show you where
your indoor unit’s filter is located. It will be either at the
indoor unit (installed internal or external to the cabinet)
or behind a return air grille in the wall or ceiling. Check
the filter monthly and clean or replace it as needed.
2. Disposable FilterDisposable filters should be
replaced with a filter of the same type and size.
NOTE − If you are unsure about the filter required for your
system, call your Lennox dealer for assistance.
IMPORTANT
Turn off electrical power to the unit at the disconnect switch before performing any maintenance.
The unit may have multiple power supplies.
3. Reusable FilterMany indoor units are equipped
with reusable foam filters. Clean foam filters with a
mild soap and water solution; rinse thoroughly; allow
filter to dry completely before returning it to the unit or
grille.
NOTE − The filter and all access panels must be in place
any time the unit is in operation.
4. Electronic Air CleanerSome systems are
equipped with an electronic air cleaner, designed to
remove airborne particles from the air passing through
the cleaner. If your system is so equipped, ask your
dealer for maintenance instructions.
5. Indoor UnitThe indoor unit’s evaporator coil is
equipped with a drain pan to collect condensate
formed as your system removes humidity from the
inside air. Have your dealer show you the location of
the drain line and how to check for obstructions. (This
would also apply to an auxiliary drain, if installed.)
IMPORTANT
Sprinklers and soaker hoses should not be installed
where they could cause prolonged exposure to the
outdoor unit by treated water. Prolonged exposure
of the unit to treated water (i.e., sprinkler systems,
soakers, waste water, etc.) will corrode the surface
of steel and aluminum parts and diminish
performance and longevity of the unit.
6. Outdoor UnitMake sure no obstructions restrict
airflow to the outdoor unit. Leaves, trash or shrubs
crowding the unit cause the outdoor unit to work harder
and use more energy. Keep shrubbery trimmed away
from the unit and periodically check for debris which
collects around the unit.
When removing debris from around the unit, be aware of
metal edges on parts and screws. Although special care
has been taken to keep exposed edges to a minimum,
physical contact with metal edges and corners while
applying excessive force or rapid motion can result in
personal injury.
Cleaning of the outdoor unit’s coil should be performed by
a trained service technician. Contact your dealer and set
up a schedule (preferably twice a year, but at least once a
year) to inspect and service your air conditioning or heat
pump system.
506109−01 10/08
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Page 23
THERMOSTAT OPERATION
Thermostat operations vary from one thermostat to
another. The following provides general operation
procedures. Refer to the user’s information manual
provided with your thermostat for specific operation
details.
Temperature
Setting Levers
Fan SwitchIn AUTO or INT (intermittent) mode, the blower
System SwitchSet the system switch for heating, cooling or auto
Temperature
Indicator
Set the lever or dial to the desired temperature
setpoints for both heating and cooling. Avoid
frequent temperature adjustment; turning the unit
offthen back onbefore pressures can equalize
will put unusual stress on the unit’s compressor.
operates only when the thermostat calls for heating
or cooling. This mode is generally preferred when
humidity control is a priority. The ON or CONT
mode provides continuous indoor blower
operation, regardless of whether the compressor
or furnace is operating. This mode is required when
constant air circulation or filtering is desired.
operation. The auto mode allows the system to
automatically switch from heating mode to cooling
mode to maintain predetermined comfort settings.
The temperature indicator displays the actual room
temperature.
PROGRAMMABLE THERMOSTATS
Your Lennox system may be controlled by a
programmable thermostat. These thermostats provide the
added feature of programmable time-of-day setpoints for
both heating and cooling. Refer to the user’s information
manual provided with your thermostat for detailed
programming and operation details.
PRESERVICE CHECK
If your system fails to operate, check the following before
calling for service:
Make sure all electrical disconnect switches are ON.
Make sure the room thermostat Temperature Selector
and System Switch (Heat, Cool, Auto) are properly
set.
Check for and replace any blown fuses, or reset any
tripped circuit breakers.
Make sure unit access panels are in place.
Make sure air filter is clean.
Write down the unit model number and have it handy
before calling.
Optional Accessories
Refer to the Lennox AC13 Engineering Handbook for the
latest available optional accessories for this unit. Below is
a list of optional accessories available at the time this
instruction was publish.
Hard Start Kit
High Pressure Switch Kit
Loss of Charge Kit
Sound Cover
Liquid Line Drier
Crankcase Heater
Page 23
AC13 SERIES
Page 24
Start−Up and Performance Checklist
Job Name Job no. Date
Job Location City State
Installer City State
Unit Model No. Serial No. Service Technician
Nameplate Voltage
Rated Load Ampacity Compressor Outdoor Fan
Maximum Fuse or Circuit Breaker
Electrical Connections Tight? Indoor Filter clean? Supply Voltage (Unit Off)
Indoor Blower RPM S.P. Drop Over Indoor (Dry) Outdoor Coil Entering Air Temp.