INSTALLATION
2006 Lennox Industries Inc.
Dallas, Texas, USA
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
qualified installer or service agency.
IMPORTANT
INSTRUCTIONS
10ACE Series Units
CONDENSER UNITS
505,128M
03/06
Supersedes 01/06
Table of Contents
10ACE Outdoor Units 1. . . . . . . . . . . . . . . . . . . . . . . . . .
Shipping & Packing List 1. . . . . . . . . . . . . . . . . . . . . . . .
General Information 2. . . . . . . . . . . . . . . . . . . . . . . . . . .
Unit Dimensions 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Setting the Unit 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Electrical 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Refrigerant Piping 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Refrigerant Metering Devices 4. . . . . . . . . . . . . . . . . . .
Manifold Gauge Set 5. . . . . . . . . . . . . . . . . . . . . . . . . . .
Service Valves 5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Leak Testing 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Evacuation 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Start−Up 7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Refrigerant Charging 8. . . . . . . . . . . . . . . . . . . . . . . . . . .
System Operation 10. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Maintenance 10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Optional Accessories 11. . . . . . . . . . . . . . . . . . . . . . . . . .
Start−Up & Performance Check List 11. . . . . . . . . . . . . .
RETAIN THESE INSTRUCTIONS
FOR FUTURE REFERENCE
Litho U.S.A.
The Clean Air Act of 1990 bans the intentional venting of refrigerant (CFC’s and HCFC’s) as of July 1,
1992. Approved methods of recovery, recycling or
reclaiming must be followed. Fines and/or incarceration may be levied for noncompliance.
WARNING
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
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.
10ACE Outdoor Units
Lennox Merit® 10ACE outdoor units are designed for use
in either fixed orifice or expansion valve (TXV) systems.
The TXV may require a field−installed hard start kit. Refer
to the Lennox Engineering Handbook for expansion valve
kits which must be ordered separately.
Shipping & Packing List
1 − Assembled outdoor unit
1 − Fixed orifice refrigerant metering device
Check the unit for shipping damage. Consult last carrier
immediately if damage is found.
03/06 505,128M
*2P0306* *P505128M*
Page 1
Unit Dimensions − inches (mm)
OPTIONAL
UNIT
STAND−OFF
KIT (4)
(Field
Installed)
4−3/8
AIR
4−3/8
(111)
OPTIONAL UNIT
STAND−OFF KIT (4)
(Field Installed)
AIRAIR
AIR
C
COIL DRAIN OUTLETS
(Around perimeter of base)
VAPOR LINE
CONNECTION
LIQUID LINE
CONNECTION
B
A
ELECTRICAL
INLETS
6−3/8
(162)
OUTDOOR
COIL FAN
COMPRESSOR
VAPOR &
LIQUID LINE
CONNECTION
(111)
COMPRESSOR
6−3/8
(162)
TOP VIEW BASE SECTION
C
DISCHARGE AIR
4−3/8
(111)
4−3/8
(111)
4−3/8
(111)
4−3/8
(111)
2 (51)
3/4 (19)
10ACE Model A B C
−024 25 (635) 24−1/4 (616) 24−1/4 (565)
−036 33 (635) 32−1/4 (616) 24−1/4 (565)
−048 33 (838) 32−1/4 (819) 24−1/4 (616)
−060 33 (940) 32−1/4 (921) 24−1/4 (718)
General Information
These instructions are intended as a general guide and do
not supersede national or local codes in any way. Consult
authorities who have jurisdiction before installation.
When servicing or repairing HVAC components, ensure
the fasteners are appropriately tightened. Table 1 shows
torque values for fasteners.
2−3/4 (70)
SIDE VIEW
Table 1
Torque Requirements
Part Recommended Torque
Service valve cap 8 ft.− lb. 11 NM
Sheet metal screws 16 in.− lb. 2 NM
Machine screws #10 28 in.− lb. 3 NM
Compressor bolts 90 in.− lb. 10 NM
Gauge port seal cap 8 ft.− lb. 11 NM
Setting the Unit
Refer to unit dimensions for sizing mounting slab, platforms or supports. Refer to figure 1 for installation clearances.
505128M 03/06
Page 2
Slab Mounting
When installing unit at grade level, install on a level slab
high enough above grade to allow adequate drainage of
water. Top of slab should be located so run−off water from
higher ground will not collect around unit.
Installation Clearances
1. Install line voltage power supply to unit from a properly
sized disconnect switch.
2. 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 (see figures 2 and 3).
Separating High/Low Voltage Field Wiring
(as noted)
(as noted)
(as noted)
*A service clearance of 30" (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" (914 mm). Clearance to one of the remaining
two sides may be 12" (304 mm) and the final side may be 6" (152
mm).
A clearance of 24" (610 mm) must be maintained between two units.
48" (1219 mm) clearance required on top of unit. Maximum soffit overhang is 36" (914 mm).
(as noted)
Figure 1
.Roof Mounting
Install the unit at a minimum of 4 inches (102 mm) above
the surface of the roof. Ensure the weight of the unit is
properly distributed over roof joists and rafters. Redwood
or steel supports are recommended.
Electrical
*−048 &
−060
models
WIRE
TIES
Figure 2
Typical Field Wiring Diagram
*
*
*
High Voltage
Field Wiring
Low Voltage
Field Wiring
Factory
Wiring
(SEE
NOTE)
208−230/60/1
In Canada, wiring must conform with current local codes and
the current Canadian Electrical Code (CEC).
WARNING
Electric Shock Hazard. Can cause injury or death.
Line voltage is present at all components on units with single-pole contactors, even when unit is not in operation!
Unit may have multiple power supplies. Disconnect all remote electric
power supplies before opening access panel.
Unit must be grounded in accordance
with national and local codes.
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
overcurrent protection size.
GROUND
WARNING! − ELECTRIC SHOCK HAZARD. Can cause INJURY
or DEATH. Unit must be grounded in accordance with national and
local codes.
NOTE − For use with copper conductors only. Refer to unit rating
plate for minimum circuit ampacity and maximum over-current
protection size.
Figure 3
3. Ground unit at unit disconnect switch or to an earth
ground.
NOTE − To facilitate conduit, a hole is located in the
bottom of the control box. Connect conduit to the control box using a proper conduit fitting. Units are approved for use only with copper conductors.
24V, Class II circuit connections are made to the low
voltage pigtails. Refer to figure 3 for field wiring diagram. A complete unit wiring diagram is located inside
the unit control box cover.
4. Install room thermostat (ordered separately) on an inside wall approximately in the center of the conditioned
area and 5 feet (1.5 m) from the floor. It should not be
installed on an outside wall or where it can be effected
by sunlight, drafts or vibrations.
Page 3
10ACE SERIES
NOTE − For proper voltages, select thermostat wire
color coded, temperature
gauge per the following chart:
Wire run length AWG # Insulation type
less than 100’ (30m) 18
more than 100’ (30m) 16
color−coded, temperature
rating 35ºC minimum
5. Install low voltage wiring from outdoor to indoor unit
and from thermostat to indoor unit. See figure 4.
Typical Field Low Voltage Wiring Diagram
Thermostat Indoor Unit
Sweat Connection Procedure
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. Wrap a wet cloth around the valve body and copper
tube stub to protect it from heat damage during brazing. Wrap another wet cloth underneath the valve body
to protect the base paint.
3. Quench the joints with a wet cloth to prevent possible
heat damage to the valve core and opening port.
4. Install a field−provided filter dryer as close as possible
to the expansion device.
R
W1
Y
G
C
power
heat
cooling
indoor blower
common
R
Outdoor Unit
W
Y
G
C
Y1
C
NOTE − see unit wiring diagram for power supply connections. If indoor unit is not equipped with blower relay. It must
be field−provided and installed (P−8−3251 or equivalent).
Figure 4
Refrigerant Piping
Field refrigerant piping consists of liquid and vapor lines
from the outdoor unit (sweat connections) to the indoor coil
(flare or sweat connections). Use Lennox L15 (sweat, nonflare) series line sets as shown in table 2 or use field-fabricated refrigerant lines. Refer to Refrigerant Piping Guide
(Corp. 9351−L9) for proper size, type, and application of
field−fabricated lines. Valve sizes are also listed in table 2.
Table 2
Refrigerant Line Kits
Valve Field Size
Connections
Liquid
Model
NOTE − Units are designed for line sets of up to 50 feet (15 m). For
applications longer than 50 feet, consult the Lennox Refrigerant Piping
Guide (Corp. 9351−L9). Select line set diameters from table 2 to ensure that oil returns to the compressor.
Line
−024
−036
−048 3/8 in
−060 3/8 in
3/8 in
(10mm)
(10 mm)
(10 mm)
Vapor
Line
3/4 in.
(19mm)
7/8 in.
(22 mm)
1−1/8 in.
(29 mm)
Recommended Line Set
Liquid
Line
3/8 in
(10mm)
3/8 in
(10 mm)
3/8 in
(10 mm)
Vapor
Line
3/4 in.
(19mm)
7/8 in.
(22 mm)
1−1/8 in.
(29 mm)
L15
Line Sets
L15−41
15 ft.− 50 ft.
(4.6 m − 15m)
L15−65
15 ft.− 50 ft.
(4.6 m − 15m)
Fabricated
Field
Refrigerant Metering Device
Use 10ACE units in either TXV systems or fixed orifice sys-
tems. See the Lennox Engineering Handbook for approved TXV and fixed orifice match-ups and application information. Table 2 lists the unit liquid and vapor line sizes
and corresponding line sets.
Fixed Orifice Systems
10ACE units are shipped with a fixed orifice refrigerant metering device. Replace the existing indoor unit fixed orifice
with the orifice supplied with the outdoor unit. Place the
supplied fixed orifice sticker on the indoor cabinet after
installation. See table 3 for the fixed orifice size for each
unit. In nonstandard applications, the provided fixed orifice
may not be appropriately sized. Refer to the Engineering
Handbook for specific orifice information.
Table 3
Fixed Orifice Drill Sizes
Unit
Catalog #
10ACE−024 100484−12 .062
10ACE−036 100484−22 .073
10ACE−048 100484−33 .086
10ACE−060 100484−44 .098
Install the fixed orifice as shown in figure 5. Do not twist the
cap tubes when loosening the seal nut from the orifice
housing.
Metering Device Installation
Fixed Orifice
O−RING
DISTRIBUTOR
NOTE − If installing expansion valve with an indoor coil
that includes a fixed orifice, remove orifice before
installing valve.
FIXED ORIFICE
EXPANSION VALVE &
O−RING (See NOTE)
STRAINER
Figure 5
Expansion Valve Systems
Expansion valves equipped with Chatleff fittings are available from Lennox. Refer to the Engineering Handbook for
expansion valves for use with specific match−ups.
Fixed Orifice
Drill Size
or
LIQUID LINE
STUB
505128M 03/06
Page 4
If you install a expansion valve with an indoor coil that
includes a fixed orifice, remove the orifice before the
expansion valve is installed.
IMPORTANT
Failure to remove the fixed orifice when installing an
expansion valve on the indoor coil will result in improper operation and damage to the system.
Manifold Gauge Set
When checking the unit charge, use a manifold gauge set
that is equipped with low loss" hoses. Do not use a manifold gauge set with anything other than a low loss" hose.
Service Valves
The service valves (liquid line − figure 6, vapor line − figures
7 and 8) and gauge ports are used for leak testing, evacuating, charging and checking charge. Each valve is
equipped with a service port which has a factory−installed
Schrader valve. A service port cap protects the Schrader
valve from contamination and serves as the primary leak
seal.
To Access Schrader Port:
1. Remove service port cap with an adjustable wrench.
2. Connect gauge to the service port.
3. When testing is complete, replace service port cap.
Tighten finger tight, then torque per table 1 (Page 2) .
To Open Front-Seated Service Valves:
1. Remove stem cap with an adjustable wrench.
2. Use a service wrench with a hex−head extension
(3/16" for liquid-line valve sizes; 5/16" for vapor-line
valve sizes) to back the stem out counterclockwise as
far as it will go.
3. Replace the stem cap. Tighten finger tight, then torque
per table 1 (Page 2) .
To Close Front-Seated Service Valves:
1. Remove the stem cap with an adjustable wrench.
2. Use a service wrench with a hex−head extension
(3/16" for liquid-line valve sizes; 5/16" for vapor-line
valve sizes) to turn the stem clockwise to seat the
valve. Tighten it firmly.
3. Replace the stem cap. Tighten finger tight, then torque
per table 1 (Page 2) .
Vapor Line Ball Valve
Ball-type service valve (10ACE−060 only, figure 8) functions the same way as the other valves but cannot be rebuilt; if one fails, replace with a new valve. The ball valve is
equipped with a service port with a factory−installed
Schrader valve. A service port cap protects the Schrader
valve from contamination and assures a leak−free seal.
Front-Seated Liquid Line Service Valve
STEM
SCHRADER
VALVE [OPEN TO
LINE SET WHEN
VALVE IS CLOSED
(FRONT SEATED)]
TO
OUTDOOR
COIL
SERVICE
PORT CAP
CAP
(VALVE FRONT-SEATED)
Valve in closed position Valve in open position
INSERT HEX
WRENCH HERE
TO
INDOOR
COIL
Figure 6
Front-Seated Vapor Line Service Valve
STEM CAP
SCHRADER VALVE
INSERT
HEX
WRENCH
HERE
TO
OUTDOOR
COIL
(VALVE
FRONT-SEATED)
Valve in closed position
[OPEN TO LINE SET
WHEN VALVE IS
CLOSED (FRONT
SEATED)]
SERVICE
PORT CAP
SERVICE PORT
TO
INDOOR
COIL
Valve in open position
Figure 7
Ball−Type Vapor Valve (Valve Closed)
STEM
USE ADJUSTABLE WRENCH
TO OPEN: ROTATE STEM
COUNTER-CLOCKWISE 90°.
TO CLOSE: ROTATE STEM
CLOCKWISE 90°.
TO
INDOOR
COIL
CAP
STEM
SERVICE PORT
SCHRADER VALVE
TO
OUTDOOR
COIL
BALL (SHOWN
CLOSED)
SERVICE
PORT CAP
Figure 8
Page 5
10ACE SERIES
Leak Testing
After the line set has been connected to the indoor and outdoor units, check the line set connections and indoor unit
for leaks.
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 unbrazing.
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.
4. Connect a cylinder of nitrogen with a pressure regulating valve to the center port of the manifold gauge set.
5. Connect the manifold gauge set high pressure hose to
the vapor valve service port. (Normally, the high pres-
sure hose is connected to the liquid line port; however,
connecting it to the vapor port better protects the manifold gauge set from high pressure damage.)
6. Adjust the nitrogen pressure to 150 psig (1034 kPa).
Open the valve on the high side of the manifold gauge
set which will pressurize line set and indoor unit.
7. After a few minutes, open a refrigerant port to ensure
the refrigerant you added is adequate to be detected.
(Amounts of refrigerant will vary with line lengths.)
Check all joints for leaks. Purge nitrogen and
HCFC-22 mixture. Correct any leaks and recheck.
Evacuation
Evacuating the system of noncondensables is critical for
proper operation of the unit. Noncondensables are defined
as any gas that will not condense under temperatures and
pressures present during operation of an air conditioning
system. Noncondensables and water vapor combine with
refrigerant to produce substances that corrode copper piping and compressor parts.
IMPORTANT
WARNING
Danger of explosion!
Can cause equipment damage, injury
or death. Never use oxygen to pressurize a refrigeration or air conditioning system. Oxygen will explode on
contact with oil and could cause personal injury.
WARNING
Danger of explosion!
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).
Using an Electronic Leak Detector or Halide
1. Connect a cylinder of HCFC-22 to the center port of
the manifold gauge set.
2. With both manifold valves closed, open the valve on
the HCFC-22 cylinder (vapor only).
3. Open the high pressure side of the manifold to allow
the HCFC-22 into the line set and indoor unit. Weigh
in a trace amount of HCFC-22. [A trace amount is a
maximum of 2 ounces (57 g) or 3 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.
Use a thermocouple or thermistor electronic vacuum
gauge that is calibrated in microns. Use an instrument
that reads from 50 microns to at least 23,000 microns.
1. Connect manifold gauge set to the service valve ports
as follows:
low pressure gauge to vapor line service valve
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 absolute
pressure of 23,000 microns (29.01 inches of mercury). 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 absolute pressure.
A rapid rise in pressure indicates a relatively large
leak. If this occurs, repeat the leak testing procedure.
NOTE − The term absolute pressure is defined as 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 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.
505128M 03/06
Page 6
CAUTION
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.
7. Shut off the nitrogen cylinder and remove the manifold
gauge hose from the cylinder. Open the manifold
gauge valves to release the 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 valves
to break the vacuum from 1 to 2 psig positive pressure
in the line set and indoor unit. Close manifold gauge
valves and shut off the HCFC-22 cylinder and remove
the manifold gauge set.
Start Up
IMPORTANT
If unit is equipped with crankcase heater, it should
be energized 24 hours before unit start−up to prevent compressor damage as a result of slugging.
1. Rotate the 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
vapor line service valves to release 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.
Page 7
10ACE SERIES
Refrigerant Charging
T
Units are factory charged with the amount of HCFC-22 refrigerant indicated on the unit nameplate. This charge is
based on a matching indoor coil and outdoor coil with a 15
ft. (4.6 m) line set. For varying lengths of line set, refer to
table 4 for refrigerant charge adjustment check.
Table 4
Refrigerant Charge per Line Set Lengths
Liquid Line
Set Diameter
5/16 in. (8 mm) 2 ounce per 5 ft. (57 g per 1.5 m)
3/8 in. (9.5 mm) 3 ounce per 5 ft. (85 g per 1.5 m)
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.
The outdoor unit should be charged during warm weather.
However, applications arise in which charging must occur
in the colder months. The method of charging is deter-
mined by the unit’s refrigerant metering device and the
outdoor ambient temperature.
Measure the liquid line temperature and the outdoor ambient temperature as outlined below:
1. Connect the manifold gauge set to the service valves:
low pressure gauge to vapor valve service port
high pressure gauge to liquid valve service port
2. Connect the center manifold hose to an upright cylinder of HCFC-22. Close manifold gauge set valves.
3. Set the room thermostat to call for heat. This will
create the necessary load for properly charging the
system in the cooling cycle.
4. Use a digital thermometer to record the outdoor ambient temperature.
5. When the heating demand has been satisfied, switch
the thermostat to cooling mode with a set point of 68F
(20C). When pressures have stabilized, use a digital
thermometer to record the liquid line temperature.
6. The outdoor temperature will determine which charging method to use. Proceed with the appropriate
charging procedure.
Charge Using Weigh−in Method (Fixed Orifice/
TXV Systems) − Outdoor Temp. <65°F (18°C)
If the system is void of refrigerant, or if the outdoor ambient
temperature is cool, use the weigh−in method to charge the
unit. Do this after any leaks have been repaired.
1. Recover the refrigerant from the unit.
Oz. per 5 ft. (g per 1.5 m) adjust
from 15 ft. (4.6 m) line set*
2. Conduct a leak check, then evacuate as previously
outlined.
3. Weigh in the charge according to the total amount
shown on the unit nameplate.
If weighing facilities are not available or if you are charging
the unit during warm weather, follow one of the other procedures outlined below.
Charge Using Subcooling Method (Fixed
Orifice Systems) − Outdoor Temp. >
If you charge a fixed orifice system when the outdoor ambient is 65F (18C) or above, use the subcooling method to
charge the unit.
1. With the manifold gauge hose still on the liquid service
port and the unit operating stably, use a digital
thermometer to record the liquid line temperature.
2. At the same time, record the liquid line pressure reading.
3. Use a temperature/pressure chart for R−22 to
determine the saturation temperature for the liquid line
pressure reading.
4. Subtract the liquid line temperature from the saturation
temperature (according to the chart) to determine
subcooling.
Saturation Temperature F (C)
Liquid Line Temperature F (C)
= Subcooling Value F (C)
5. Compare the subcooling value with those in table 5. If
subcooling is greater than shown, recover some
refrigerant. If subcooling is less than shown, add some
refrigerant.
65°F (18°C)
Table 5
Subcooling Values for Fixed Orifice Systems
Outdoor
emp.
F (C)
65 (18) 10 (5.6) 17 (9.5) 15 (8.3) 14 (8)
70 (21) 9 (5) 17 (9.5) 14 (8) 15 (8.3)
75 (24) 8 (4.5) 16 (9) 13 (7) 15 (8.3)
80 (27) 7 (3.9) 15 (8.3) 13 (7) 14 (8)
85 (29) 6 (3.3) 14 (8) 12 (6.7) 14 (8)
90 (32) 5 (2.8) 14 (8) 12 (6.7) 13 (7)
95 (35) 4 (2.2) 12 (6.7) 12 (6.7) 13 (7)
100 (38) 4 (2.2) 11 (6) 11 (6) 12 (6.7)
105 (41) 3 (1.7) 10 (5.6) 10 (5.6) 12 (6.7)
110 (43) 3 (1.7) 9 (5) 9 (5) 11 (6)
115 (45) 2 (1.1) 8 (4.5) 8 (4.5) 10 (5.6)
10ACE−24 10ACE−36 10ACE−48 10ACE−60
Liquid Subcooling [+ 1_F (.6_C)]
505128M 03/06
Page 8
Charge Using Approach Method (TXV Systems)
Temp5F
− Outdoor Temperature >
The following procedure is intended as a general guide and
is for use on expansion valve (TXV) systems only. For best
results, indoor temperature should be 70°F (21°C) to 80°F
(26°C). Monitor system pressures while charging.
1. Record outdoor ambient temperature using a digital
thermometer.
2. Attach high pressure gauge set and operate unit for
several minutes to allow system pressures to stabilize.
3. Compare stabilized pressures with those provided in
table 7, Normal Operating Pressures."
65°F (18°C)
IMPORTANT
Use table 7 to help perform maintenance checks.
Table 7 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.
Pressures higher than those listed indicate that the
system is overcharged. Pressures lower than those
listed indicate that the system is undercharged.
Verify adjusted charge using the approach method.
NOTE − For best results, use the same digital thermometer to check both outdoor ambient and liquid
temperatures.
4. Check the liquid line temperature. The difference between the ambient and liquid temperatures should
match values given in table 6. Loss of charge results
in low capacity and efficiency.
5. If the values do not agree with the those in table 6, add
refrigerant to lower the approach temperature, or recover refrigerant from the system to increase the approach temperature.
Table 6
Approach Values
10ACE Model −024 −036 −048 −060
Temp. °F (°C) 18 (10) 11 (6) 8 (4.5) 13 (7)
Approach Value is the Liquid Line Temperature minus Outdoor Ambient Temperature [ºF (ºC) + 1ºF (0.5ºC)]
Table 7
Normal Operating Pressures*
10ACE−024 10ACE−036 10ACE−048 10ACE−060
5
(5C)**
Expansion Valve
65 (18) 163 70 162 70 159 71 170 74
75 (24) 193 71 187 74 188 72 201 76
85 (29) 225 72 219 75 220 73 234 77
95 (35) 260 73 253 77 251 76 270 79
105 (41) 298 74 291 79 290 77 309 79
110 (43) 318 75 310 80 309 78 331 80
115 (45) 338 75 329 81 328 79 351 81
Fixed Orifice
65 (18) 165 63 168 67 163 68 189 72
75 (24) 194 67 195 71 190 71 203 74
85 (29) 224 70 224 75 220 74 233 77
95 (35) 257 73 255 78 251 77 265 79
105 (41) 293 76 289 82 288 79 301 82
110 (43) 313 78 305 83 307 80 319 83
115 (45) 332 79 324 84 325 82 339 84
* Values shown are typical pressures (in. psig +2psig); indoor unit
match up, indoor air quality equipment, and indoor load will cause
the pressures to vary.
** Temperature of the air entering the outside coil.
Liq. Suc. Liq. Suc. Liq. Suc. Liq. Suc.
Page 9
10ACE SERIES
System Operation
The outdoor unit and indoor blower cycle on demand from
the room thermostat. When the thermostat blower switch
is in the ON position, the indoor blower operates continu-
ously.
Maintenance
NOTE − White residue may surface on guards and grilles
of outdoor units. This is caused by mild acids present in
minute quantities in the plasticizer applied to make the
coating flexible. The residue is comprised of non−toxic,
common fatty acids found in natural animal and vegetable
oils, and can be removed by wiping the parts with a cloth.
Once outside, and over time, the rain will wash off any remaining residue.
Maintenance and service must be performed by a qualified
installer or service agency. At the beginning of each cooling season, the system should be checked as follows:
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.
1. Clean and inspect the outdoor coil. The coil may be
flushed with a water hose. Make sure power is off before cleaning.
The outdoor coil is protected by an inner mesh screen
and a wire cage (see figure 9).
6 pins
If debris has collected between the mesh screen and
the coil and cannot be dislodged by spraying unpressurized water from the inside coil surface to the outside, the mesh may be removed by first removing the
top of the unit which will allow for removal of the wire
cage.
Then, using pliers to grip the head of the push pins, pull
straight out to extract the push pins along one side of
the coil. If necessary, remove the push pins along the
back of the unit; it is usually unnecessary to fully remove the inner mesh screen.
Drape the mesh screen back and wash the coil. When
all the debris has been removed from the coil, reinstall
the mesh screen by positioning it in its original position
and reinserting the push pin. No tool is required to
push the pin back into the same slot in the fins.
If the push pin is loose and tends not to stay in place,
brush the fins with a 22 fpi fin brush (except model
−024, 18 fpi). Line up the push pin a couple fins to the
right or left of the original hole and re−insert the pin.
2. Condenser fan motor is prelubricated 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 unit (unit operating).
6. Check amp−draw condenser fan motor.
Unit nameplate _________ Actual ____________ .
NOTE − If the owner reports insufficient cooling, the
unit should be gauged and the refrigerant charge
should be checked. Refer to the charging section in
this instruction.
PUSH PIN
MESH SCREEN
505128M 03/06
Figure 9
Indoor Coil
1. Clean coil, if necessary.
2. Check connecting lines and coils for evidence of oil
leaks.
3. Check the condensate pan line and clean it 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. Belt Drive Blowers − Check belt for wear and proper
tension.
4. Check all wiring for loose connections
5. Check for correct voltage at unit (blower operating).
6. Check amp−draw on blower motor
Unit nameplate_________ Actual ____________.
Page 10
Optional Accessories
Refer to the Engineering Handbook for optional accessories that may apply to this unit. The following may or may
not apply:
Loss of Charge Kit
High Pressure Switch Kit
Compressor Monitor
Compressor Crankcase Heater (standard on 4 and 5
ton units)
Hail Guards
Mounting Bases
Timed Off Control
Stand−off Kit
Sound Cover
Low Ambient Kit
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.
Discharge Pressure Vapor Pressure Refrigerant Charge Checked?
Refrigerant Lines: Leak Checked? Properly Insulated? Outdoor Fan Checked?
Service Valves: Fully Opened? Caps Tight? Thermostat
Voltage With Compressor Operating Calibrated? Properly Set? Level?
Page 11
10ACE SERIES
Loading...