Refrigerant Piping; Refrigerant Metering Devices - Lennox 10ACE Series Installation Instructions Manual

NOTE − For proper voltages, select thermostat wire
gauge per the following chart:
Wire run length
less than 100' (30m)
more than 100' (30m)
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
power
R
heat
W1
cooling
Y
indoor blower
G
common
C
NOTE − see unit wiring diagram for power supply connec-
tions. 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, non-
flare) series line sets as shown in table 2 or use field-fabri-
cated 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.
Refrigerant Line Kits
Valve Field Size
Connections
Liquid Vapor
Line Line
Model
−024 3/8 in 3/4 in.
−036 (10mm) (19mm)
−048 3/8 in 7/8 in.
(10 mm) (22 mm)
−060 3/8 in 1−1/8 in.
(10 mm) (29 mm)
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 en-
sure that oil returns to the compressor.
505128M 03/06
AWG # Insulation type
18
color−coded, temperature color coded, temperature
º º
rating 35 C minimum
16
Indoor Unit
R
Outdoor Unit
W
Y1
Y
G
C
C
Table 2
Recommended Line Set
Liquid Vapor L15
Line Line Line Sets
3/8 in 3/4 in. L15−41
(10mm) (19mm) 15 ft.− 50 ft.
(4.6 m − 15m)
3/8 in 7/8 in. L15−65
(10 mm) (22 mm) 15 ft.− 50 ft.
(4.6 m − 15m)
3/8 in 1−1/8 in. Field
(10 mm) (29 mm) Fabricated
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 braz-
ing. 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.
Refrigerant Metering Device
Use 10ACE units in either TXV systems or fixed orifice sys-
tems. See the Lennox Engineering Handbook for ap-
proved TXV and fixed orifice match-ups and application in-
formation. 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 me-
tering 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.
Fixed Orifice Drill Sizes
Unit
10ACE−024
10ACE−036
10ACE−048
10ACE−060
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
O−RING
DISTRIBUTOR
NOTE − If installing expansion valve with an indoor coil
that includes a fixed orifice, remove orifice before
installing valve.
Expansion Valve Systems
Expansion valves equipped with Chatleff fittings are avail-
able from Lennox. Refer to the Engineering Handbook for
expansion valves for use with specific match−ups.
Page 4
Table 3
Fixed Orifice Fixed Orifice
Catalog # Drill Size
100484−12 .062
100484−22 .073
100484−33 .086
100484−44 .098
FIXED ORIFICE
or
EXPANSION VALVE &
O−RING (See NOTE)
LIQUID LINE
STUB
STRAINER
Figure 5