Lennox CBA25UHE Series Installation and operation manual

Page 1
WARNING
Improper installation, adjustment, alteration, service
or maintenance can cause property damage, personal
injury or loss of life. Installation and service must be
performed by a licensed professional HVAC installer or
equivalent, service agency, or the gas supplier.
IMPORTANT
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.
NOTICE
A thermostat is not included and must be ordered
separately.
• In non-communicating applications, the Lennox
ComfortSense® thermostat may be used, as well as
other non-communicating thermostats.
In all cases, setup is critical to ensure proper system
operation.
Field wiring for non-communicating applications is
illustrated in diagrams, which begin on page 25.
CAUTION
As with any mechanical equipment, contact with sharp
sheet metal edges can result in personal injury. Take
care while handling this equipment and wear gloves and
protective clothing.
CBA25UHE
IMPORTANT: Special procedures are required for clean-
ing the all-aluminum coil in this unit. See page 25 in this
instruction for information.
Table of Contents
CBA25UHE Unit Dimensions – Upow – inches (mm)...2
CBA25UHE Unit Dimensions – Horiz. – inches (mm) ....3
Specications and Electrical Data ..................................4
Model Number Identication...........................................5
Blower Data....................................................................6
Unit Components............................................................8
ECBA25 Electric Heat Data............................................9
Heat Section Installation...............................................13
Conguration Modication ...........................................15
Brazing Connections ...................................................17
Installing the Condensate Drain ..................................20
Electrical Connections .................................................22
Inspecting and Replacing Filters .................................23
Wiring Diagrams...........................................................23
Professional Maintenance ...........................................25
Check-out Procedures .................................................25
Sequence of Operation ................................................26
Constant Torque Speed Blower Motor (ECM) (B3) ....26
Service Literature
UNIT INFORMATION
100073
July 31, 2023
CBA25UHE (HFC-410A) SERIES UNITS
General Information
This indoor unit with all-aluminum coil is designed for
installation with optional eld-installed electric heat and a
matched outdoor unit that is charged with HFC-410A re-
frigerant. These units, designed for indoor installation in
multiple positions, are completely assembled for upow
and horizontal right-hand discharge before being shipped
from the factory.
All CBA25UHE air handlers are equipped with a facto-
ry-installed, internally mounted check / expansion valve,
which is suitable for use in HFC-410A applications.
This air handler is compatible with the ComfortSense®
non-communicating thermostat and any conventional
non-communicating 24VAC thermostat.
NOTE - For downow or horizontal left-hand air discharge,
certain eld modications are required.

Page 2
CBA25UHE Unit Dimensions – Upow – inches (mm)
A
B
FRONT VIEW SIDE VIEW
LINE VOLTAGE
INLETS
(Top and Right Side)
LOW VOLTAGE
INLETS
(Either Side)
SUCTION
LINE
LIQUID
LINE
FILTER
ACCESS
3/4
(19)
AIR FLOW
CIRCUIT
BREAKER
COVER
D
1-1/8
(29)
1/2
(13)
C
LINE VOLTAGE
INLETS
(Top and Left Side)
LINE VOLTAGE
INLETS
(Top and Right Side)
1 (25)
SUPPLY AIR
OPENING
TOP VIEW
OPENING OPENING
1 (25) 1 (25)
1-1/8
(29)
1-1/8
(29)
20-3/8
(518)
22
(559)
14-1/2
(368)
DETAIL OF PIPING PLATE
LIQUID
LINE CONDENSATE
DRAINS (2)
(Horizontal)
1-3/4
(44)
3/4 (19)
2-3/4
(70)
3-1/2
(89)
PIPING
PLATE
4-3/4
(121)
4-3/8
(111)
2-3/8
(60)
CONDENSATE
DRAINS (2)
(Upflow and
Downflow)
SUCTION
LINE
CONDENSATE DRAIN
PIPING PLATE (3)
(2-1/4 x 3-3/4)
Dimensions 024 030036, 042
in. mm in. mm in.mm
A45-1/2 1156 47 1194 53-5/81362
B18-1/2 470 18-1/2 470 21-1/2546
C16-1/2 419 16-1/2 419 19-1/2495
D16-1/4 413 16-1/4 413 19-1/4489

Page 3
CBA25UHE Unit Dimensions – Horiz. – inches (mm)
A
B
FRONT VIEWEND VIEW
LINE VOLTAGE INLETS
(Top and Right Side)
LOW VOLTAGE INLETS
(Either Side)
SUCTION
LINE
LIQUID
LINE
FILTER
ACCESS
CONDENSATE DRAIN
PIPING PLATE (3)
(2-1/4 x 3-3/4)
3/4
(19)
AIR FLOW
CIRCUIT
BREAKER
COVER
D
1-1/8
(29)
1/2
(13)
C
LINE VOLTAGE
INLETS
(Top and Left Side)
LINE VOLTAGE
INLETS
(Top and Right Side)
1 (25)
SUPPLY AIR
OPENING
TOP VIEW
OPENING
OPENING
1 (25)
1 (25)
1-1/8
(29)
1-1/8
(29)
20-3/8
(518)
22
(559)
14-1/2
(368)
DETAIL OF PIPING PLATE
LIQUID
LINE
CONDENSATE
DRAINS (2)
(Horizontal)
1-3/4
(44)
3/4
(19)
2-3/4
(70)
3-1/2
(89)
4-3/4
(121)
4-3/8
(111)
2-3/8
(60)
CONDENSATE
DRAINS (2)
(Upflow and
Downflow)
SUCTION
LINE
PIPING
PLATE
Dimensions 024 030036, 042
in. mm in.mmin. mm
A45-1/2 1156 47 1194 53-5/81362
B18-1/2 470 18-1/2470 21-1/2546
C16-1/2 419 16-1/2419 19-1/2495
D16-1/4 413 16-1/4413 19-1/4489

Page 4
Specications and Electrical Data
General
Data
Model Number CBA25UHE-024 CBA25UHE-030 CBA25UHE-036 CBA25UHE-042
Nominal tonnage 22.5
33
.5
Connections Suction/Vapor line (o.d.) - in. sweat 3/4 3/47/8 7/8
Liquid line (o.d.) - in. sweat 3/8 3/83/8 3/8
Condensate - in. fpt (2) 3/4 (2) 3/4(2) 3/4(2) 3/4
Indoor
Coil
Net face area - ft.23.77 4.72 5.66 5.66
Tube outside diameter - in. 3/8 3/83/8 3/8
Number of rows
3333
Fins per inch 15 15 15 15
Blower Wheel nominal diameter x width - in. 10 x 810 x 810 x 812 x 10
Blower motor output - hp 1/2 1/21/2 3/4
1Filters 15 x 20 x 115 x 20 x 118 x 20 x 118 x 20 x 1
Shipping Data -1 package - lbs. 127 133163 168
ELECTRICAL DATA
Voltage - 1 phase (60 hz) 208/230V208/230V 208/230V 208/230V
2Maximum overcurrent protection (unit only) 15 15 15 15
3Minimum circuit ampacity (unit only)
5558
Blower Motor Full Load Amps 4.1 4.14.1 6.0
1
2HACR type circuit breaker or fuse.
3Refer to National or Canadian Electrical Code manual to determine wire, fuse and disconnect size requirements. Use wires suitable for at least 167°F.
OPTIONAL ACCESSORIES - ORDER SEPARATELY
Model -024
-030
-036 -042
M30 Smart Wi-Fi Thermostat 15Z6915Z69 15Z69
Remote Outdoor Temperature Sensor X2658 X2658 X2658
Y9658 Y9659 Y9659
Electric Heat - See Electric Heat Data Tables 4 to 15 kW
Horizontal Support Frame Kit 56J1856J1856J18
45K3245K3245K32
Single-Point Power Source Control Box (for Electric Heat) 21H3921H3921H39
45K3045K3045K30
High Performance Economizer (Commercial Only) 10U5310U5310U53
INSTALLATION CLEARANCES WITH ELECTRIC HEAT
Cabinet 0 inch (0 mm)
To Plenum 0 inch (0 mm)
To Outlet Duct within 3 feet (914 mm) 0 inch (0 mm)
Floor 0 inch (0 mm) See Note #1
Service / Maintenance See Note #2
1
2Front service access - 24 inches (610 mm) minimum.
NOTE - If cabinet depth is more than 24 inches (610 mm), allow a minimum of the cabinet depth plus 2 inches (51 mm).

Page 5
Model Number Identication
CB A 25 UH E - 030 - 230 - 01
Unit Type
CB = Air Handler
Refrigerant Type
A = Aluminum Coil/R-410A
Series
Nominal Cooling Capacity
024 = 2 tons
030 = 2.5 tons
036 = 3 tons
042 = 3.5 tons
Minor Revision Number
Voltage
230 = 208/230V-1 phase-60hz
Blower Motor
Air Flow – Cooling Blower Speed
The cooling blower speed is factory congured to provide
correct air ow for an outdoor unit that matches the cool-
ing capacity rating of the air handler.
If the outdoor unit is smaller than the maximum cooling ca-
pacity rating for the air handler, the cooling blower speed
may need to be changed. Refer to blower performance
charts on pages 6 and 7.
WARNING
Electric shock hazard! - Disconnect all power
supplies before servicing.
Replace all parts and panels before
operating.
Failure to do so can result in death or
electrical shock.
ADJUSTING BLOWER SPEED
Motor Speed Taps
NOTE – Motor is programmed for a 45-second OFF delay
on all speed taps except TAP #4 (electric heat 120-second
OFF delay).
These settings are for nominal tonnage match-ups with
the units. When matched with other sizes, it is recom-
mended that the CFM be adjusted to approximately 400
CFM per ton.
Tap Operation Remarks
1 Continuous fan Continuous fan speed is
energized (24 volt input to G).
2 Lower tonnage
speed nominal capacity (e.g. if 3-ton
air handler is used with 2.5-ton
outdoor unit).
3 A/C or heat pump -
no electric heat at minimum static allowed.
4* A/C or Heat pump
with electric heat ton at .5 static. Energized when
electric heat element has a call
for heat.
5 High static
applications at .8 static.
* Tap 4 is minimum setting for electric heat
TABLE 1

Page 6
Blower Data
CBA25UHE-024 PERFORMANCE
External
Static
Pressure
in. w.g.
Air Volume / Watts at Various Blower Speeds
Tap 1Tap 2Tap 3Tap
4T
ap 5
cfmWatts cfmWatts cfmWatts cfmWatts cfmWatts
0.10676 64 72878820 1071015 180 1054 194
0.20612 71 67981780 114981 188 1020 203
0.30514 77 61493752 120953 195 987 212
0.40448 83 517102 712126 922 204 958 219
0.50400 86 461106 678133 899 210 940 226
0.60337 92 406112 598142 865 219 902 235
0.70270 100346 119535 147831 224 881 241
0.80203 103280 127495 153799 237 833 248
NOTE -
Electric heaters have no appreciable air resistance.
CBA25UHE-030 PERFORMANCE
External
Static
Pressure
in. w.g.
Air Volume / Watts at Various Blower Speeds
Tap 1Tap 2Tap 3Tap
4T
ap 5
cfmWatts cfmWatts cfmWatts cfmWatts cfmWatts
0.10775 87 898125 999160 1132 219 1341 346
0.20731 94 863131 965168 1099 229 1309 357
0.30690 100830 138936 1751068 237 1289 364
0.40647 106793 145899 1841041 245 1259 376
0.50565 115755 152870 1911014 254 1239 385
0.60522 118725 160833 197985 261 1197 389
0.70474 125635 168797 208957 269 1168 395
0.80406 132590 174715 218928 278 1139 403
NOTE -
Electric heaters have no appreciable air resistance.
CBA25UHE-036 PERFORMANCE
External
Static
Pressure
in. w.g.
Air Volume / Watts at Various Blower Speeds
Tap 1Tap 2Tap 3Tap
4T
ap 5
cfmWatts cfmWatts cfmWatts cfmWatts cfmWatts
0.10865 94 1103 1621303250 1415 312 1523 386
0.20812 1041060172 1268 2611381 325 1492 399
0.30747 1131013184 1234 2711352 336 1462411
0.40674 119970 1931199283 1316 348 1434 423
0.50620 125915 2051153295 1285 360 1403 434
0.60565 131841 2141117306 1238 377 1363 452
0.70484 138790 2211047323 1202 386 1315 456
0.80422 144754 2291004326 1134 396 1281 467
NOTE -
Electric heaters have no appreciable air resistance.

Page 7
CBA25UHE-042 PERFORMANCE
External
Static
Pressure
in. w.g.
Air Volume / Watts at Various Blower Speeds
Tap 1Tap 2Tap 3Tap
4T
ap 5
cfm Watts cfm Watts cfm Watts cfmWatts cfmWatts
0.10 982 132 1275 270 1446 390 1560 473 1656 569
0.20 923 140 1233 280 1413 402 1526 488 1624 581
0.30 866 148 1199 287 1362 411 1500 498 1594 591
0.40 812 153 1159 296 1357 420 1469 510 1563 602
0.50 745 162 1120 304
312
1325 429 1437 520 1543 613
0.60 686 169 1081 1292 438 1413 530 1505 615
0.70 642 176 1029 322 1257 448 1345 543 1456 613
0.80 568 185 981 331 1221 458 1335 544 1417 612
NOTE -
Electric heaters have no appreciable air resistance.

Page 8
UPFLOW DRAIN PAN
EXPANSION VALVE
COIL
BLOWER COMPARTMENT
CONTROL BOX
ELECTRIC HEAT
FIGURE 1. Typical Unit Parts Arrangement
Application
All major blower coil components must be matched ac-
cording to Lennox recommendations for the unit to be
covered under warranty. Refer to the Product Specica-
tion bulletin for approved system matchups. A misapplied
system will cause erratic operation and can result in early
unit failure.
The units come with factory installed check and expan-
sion valve for all applications. The TXV valve has been
installed internally for a cleaner installation and is acces-
sible if required.
Unit Components
CONTROL BOX
The CBA25UHE control box is located above the blower
section shown in gure 1. Line voltage and electric heat
connections are made in the control box. Optional electric
heat ts through an opening located in the center of the
control box. When electric heat is not used, cover plates
cover the opening. The electric heat control arrangement
is detailed in the electric heat section of this manual.
TRANSFORMER
All CBA25UHE series units use a single line voltage to
24VAC transformer mounted in the control box. The
transformer supplies power to the control circuits in the
indoor and outdoor unit. Transformers are rated at 40VA.
208/240VAC single phase transformers use two primary
voltage taps as shown in gure 2.
BLUE
YELLOW
ORANGE
RED
BLACK
240 VOLTS
208 VOLTS
PRIMARY SECONDARY
FIGURE 2. 208 / 240 Volt Transformer
BLOWER MOTOR (B3)
CBA25UHE-024, -030, -036 and -042 units use single-phase
direct drive constant torque blower motors. Figure 3 shows
the parts arrangement. All motors have ve speed taps. Typ-
ically, speed tap #3 is energized during normal operation.
All units are factory wired for heat pump and cooling ap-
plications with or without electric heat. The unit wiring dia-
grams will provide factory set blower speeds.
See motor detail section on page 28.
BLOWER ASSEMBLY
Motor Terminals
FIGURE 3. Blower Assembly
COIL
CBA25UHE units have dual slab coils arranged in an A
conguration. Each coil has two or three rows of aluminum
tubes tted with ripple-edged aluminum ns. An expansion
valve feeds multiple parallel circuits through the coils. The
coil is designed to easily slide out of the unit cabinet.
PLASTIC DRAIN PANS
Drain pans are provided and installed on the CBA25UHE.
The drain pans are made from berglass lled plastic.

Page 9
ECBA25 Electric Heat Data
ELECTRIC HEAT DATA CBA25UHE-024 | SINGLE PHASE
Electric Heat
Model Number
Input Blower
Motor
Full Load
Amps
2Minimum
Circuit
Ampacity
3Maximum
Overcurrent
Protection
Volt kW 1Btuh
4 kW ECBA25-4 (19V31)
Terminal Block
ECBA25-4CB (19V32)
30A Circuit Breaker
208 3.0 10,250 4.1234 25
220 3.4 11,450 4.1244 25
230 3.7 12,550 4.1254 25
240 4.0 13,650 4.12
63
0
5 kW ECBA25-5 (16Y36)
Terminal Block
ECBA25-5CB (16Y39)
30A Circuit Breaker
208 3.6 12,300 4.12
73
0
220 4.0 13,800 4.12
83
0
230 4.4 15,000 4.12
93
0
240 4.8 16,400 4.13
03
0
7.5 kW ECBA25-7.5 (16Y37)
Terminal Block
ECBA25-7.5CB (16Y41)
45A Circuit Breaker
208 5.6 19,200 4.1394 40
220 6.3 21,500 4.14
14
5
230 6.9 23,500 4.14
34
5
240 7.5 25,600 4.14
44
5
10 kW ECBA25-10 (16Y38)
Terminal Block
ECBA25-10CB (16Y42)
60A Circuit Breaker
208 7.2 24,600 4.1484 50
220 8.0 27,500 4.15
16
0
230 8.8 30,000 4.15
36
0
240 9.6 32,700 4.15
56
0
NOTE - Circuit 1 Minimum Circuit Ampacity includes the Blower Motor Full Load Amps.
1Electric heater capacity only - does not include additional blower motor heat capacity.
2Refer to National or Canadian Electrical Code manual to determine wire, fuse and disconnect size requirements. Use wires suitable for at least 167°F.
3HACR type breaker or fuse.
4Bold indicates that the circuit breaker on “CB” circuit breaker models must be replaced with size shown. See table on page 11.

Page 10
ELECTRIC HEAT DATA CBA25UHE-030 | SINGLE PHASE
Electric Heat
Model Number
Input Blower
Motor
Full Load
Amps
2Minimum
Circuit
Ampacity
3Maximum
Overcurrent
Protection
Single Point
Power Source
Volt kW 1Btuh Ckt 1Ckt 2Ckt 1Ckt 2
2Minimum
Circuit
Ampacity
3Maximum
Overcurrent
Protection
4 kW ECBA25-4 (19V31)
Terminal Block
ECBA25-4CB (19V32)
30A Circuit Breaker
208 3.0 10,250 4.123-- - 4 25 - - --- --- -
220 3.4 11,450 4.124-- - 4 25 - - --- --- -
230 3.7 12,550 4.125-- - 4 25 - - --- --- -
240 4.0 13,650 4.126-- -30-- --- --- -
5 kW ECBA25-5 (16Y36)
Terminal Block
ECBA25-5CB (16Y39)
30A Circuit Breaker
208 3.6 12,300 4.127-- -30-- --- --- -
220 4.0 13,800 4.128-- -30-- --- --- -
230 4.4 15,000 4.129-- -30-- --- --- -
240 4.8 16,400 4.130-- -30-- --- --- -
7.5 kW ECBA25-7.5 (16Y37)
Terminal Block
ECBA25-7.5CB (16Y41)
45A Circuit Breaker
208 5.6 19,200 4.139-- - 4 40 - - --- --- -
220 6.3 21,500 4.141-- -45-- --- --- -
230 6.9 23,500 4.143-- -45-- --- --- -
240 7.5 25,600 4.144-- -45-- --- --- -
10 kW ECBA25-10 (16Y38)
Terminal Block
ECBA25-10CB (16Y42)
60A Circuit Breaker
208 7.2 24,600 4.148-- - 4 50 - - --- --- -
220 8.0 27,500 4.151-- -60-- --- --- -
230 8.8 30,000 4.153-- -60-- --- --- -
240 9.6 32,700 4.155-- -60-- --- --- -
12.5 kW ECBA25-12.5CB (16Y43)
(1) 50A and
(1) 25A Circuit Breaker
208 9.4 32,000 4.143194 45 4 20 62 70
220 10.5 35,800 4.145204 45 4 20 65 70
230 11.5 39,200 4.1472150256870
240 12.5 42,600 4.1492250257070
15 kW ECBA25-15CB (16Y44)
(1) 60A and
(1) 25A Circuit Breaker
208 10.8 36,900 4.148224 50 25 70 70
220 12.1 41,300 4.1512360257480
230 13.2 45,100 4.1532460257780
240 14.4 49,100 4.1552560258080
NOTE - Circuit 1 Minimum Circuit Ampacity includes the Blower Motor Full Load Amps.
1Electric heater capacity only - does not include additional blower motor heat capacity.
2Refer to National or Canadian Electrical Code manual to determine wire, fuse and disconnect size requirements. Use wires suitable for at least 167°F.
3HACR type breaker or fuse.
4Bold indicates that the circuit breaker on “CB” circuit breaker models must be replaced with size shown. See table on page 11.

Page 11
ELECTRIC HEAT DATA CBA25UHE-036 | SINGLE PHASE
Electric Heat
Model Number
Input Blower
Motor
Full Load
Amps
2Minimum
Circuit
Ampacity
3Maximum
Overcurrent
Protection
Single Point
Power Source
Volt kW 1Btuh Ckt 1Ckt 2Ckt 1Ckt 2
2Minimum
Circuit
Ampacity
3Maximum
Overcurrent
Protection
4 kW ECBA25-4 (19V31)
Terminal Block
ECBA25-4CB (19V32)
30A Circuit Breaker
208 3.0 10,250 4.1 23 - - - 4 25 - - --- --- -
220 3.4 11,450 4.1 24 - - - 4 25 - - --- --- -
230 3.7 12,550 4.1 25 - - - 4 25 - - --- --- -
240 4.0 13,650 4.1 26 - - -30-- --- --- -
5 kW ECBA25-5 (16Y36)
Terminal Block
ECBA25-5CB (16Y39)
30A Circuit Breaker
208 3.6 12,300 4.1 27 - - -30-- --- --- -
220 4.0 13,800 4.1 28 - - -30-- --- --- -
230 4.4 15,000 4.1 29 - - -30-- --- --- -
240 4.8 16,400 4.1 30 - - -30-- --- --- -
7.5 kW ECBA25-7.5 (16Y37)
Terminal Block
ECBA25-7.5CB (16Y41)
45A Circuit Breaker
208 5.6 19,200 4.1 39 - - - 4 40 - - --- --- -
220 6.3 21,500 4.1 41 - - -45-- --- --- -
230 6.9 23,500 4.1 43 - - -45-- --- --- -
240 7.5 25,600 4.1 44 - - -45-- --- --- -
10 kW ECBA25-10 (16Y38)
Terminal Block
ECBA25-10CB (16Y42)
60A Circuit Breaker
208 7.2 24,600 4.1 48 - - - 4 50 - - --- --- -
220 8.0 27,500 4.1 51 - - -60-- --- --- -
230 8.8 30,000 4.1 53 - - -60-- --- --- -
240 9.6 32,700 4.1 55 - - -60-- --- --- -
12.5 kW ECBA25-12.5CB (16Y43)
(1) 50A and
(1) 25A Circuit Breaker
208 9.4 32,000 4.1 43 19 4 45 4 20 62 70
220 10.5 35,800 4.1 45 20 4 45 4 20 65 70
230 11.5 39,200 4.1 47 21 50 25 68 70
240 12.5 42,600 4.1 49 22 50 25 70 70
15 kW ECBA25-15CB (16Y44)
(1) 60A and
(1) 25A Circuit Breaker
208 10.8 36,900 4.1 48 22 4 50 25 70 70
220 12.1 41,300 4.1 51 23 60 25 74 80
230 13.2 45,100 4.1 53 24 60 25 77 80
240 14.4 49,100 4.1 55 25 60 25 80 80
NOTE - Circuit 1 Minimum Circuit Ampacity includes the Blower Motor Full Load Amps.
1Electric heater capacity only - does not include additional blower motor heat capacity.
2Refer to National or Canadian Electrical Code manual to determine wire, fuse and disconnect size requirements. Use wires suitable for at least 167°F.
3HACR type breaker or fuse.
4Bold indicates that the circuit breaker on “CB” circuit breaker models must be replaced with size shown. See table on page 11.

Page 12
ELECTRIC HEAT DATA CBA25UHE-042 | SINGLE PHASE
Electric Heat
Model Number
Input Blower
Motor
Full Load
Amps
2Minimum
Circuit
Ampacity
3Maximum
Overcurrent
Protection
Single Point
Power Source
Volt kW 1Btuh Ckt 1Ckt 2Ckt 1Ckt 2
2Minimum
Circuit
Ampacity
3Maximum
Overcurrent
Protection
4 kW ECBA25-4 (19V31)
Terminal Block
ECBA25-4CB (19V32)
30A Circuit Breaker
208 3.0 10,250 6.026-- -30-- --- --- -
220 3.4 11,450 6.027-- -30-- --- --- -
230 3.7 12,550 6.027-- -30-- --- --- -
240 4.0 13,650 6.028-- -30-- --- --- -
5 kW ECBA25-5 (16Y36)
Terminal Block
ECBA25-5CB (16Y39)
30A Circuit Breaker
208 3.6 12,300 6.029-- -30-- --- --- -
220 4.0 13,800 6.030-- -30-- --- --- -
230 4.4 15,000 6.031-- - 4 35 - - --- --- -
240 4.8 16,400 6.033-- - 4 35 - - --- --- -
7.5 kW ECBA25-7.5 (16Y37)
Terminal Block
ECBA25-7.5CB (16Y41)
45A Circuit Breaker
208 5.6 19,200 6.041-- -45-- --- --- -
220 6.3 21,500 6.043-- -45-- --- --- -
230 6.9 23,500 6.045-- -45-- --- --- -
240 7.5 25,600 6.047-- - 4 50 - - --- --- -
10 kW ECBA25-10 (16Y38)
Terminal Block
ECBA25-10CB (16Y42)
60A Circuit Breaker
208 7.2 24,600 6.051-- -60-- --- --- -
220 8.0 27,500 6.053-- -60-- --- --- -
230 8.8 30,000 6.055-- -60-- --- --- -
240 9.6 32,700 6.058-- -60-- --- --- -
12.5 kW ECBA25-12.5CB (16Y43)
(1) 50A and
(1) 25A Circuit Breaker
208 9.4 32,000 6.045194 45 4 20 64 70
220 10.5 35,800 6.04720504 20 67 70
230 11.5 39,200 6.0492150257070
240 12.5 42,600 6.051224 60 25 73 80
15 kW ECBA25-15CB (16Y44)
(1) 60A and
(1) 25A Circuit Breaker
208 10.8 36,900 6.0512260257380
220 12.1 41,300 6.0532360257680
230 13.2 45,100 6.0552460257980
240 14.4 49,100 6.0582560258390
NOTE - Circuit 1 Minimum Circuit Ampacity includes the Blower Motor Full Load Amps.
1Electric heater capacity only - does not include additional blower motor heat capacity.
2Refer to National or Canadian Electrical Code manual to determine wire, fuse and disconnect size requirements. Use wires suitable for at least 167°F.
3HACR type breaker or fuse.
4Bold indicates that the circuit breaker on “CB” circuit breaker models must be replaced with size shown. See table on page 11.
REPLACEMENT CIRCUIT BREAKERS
Voltage DescriptionCatalog No.
208/240V - 1 Phase 25 amp, 2 pole 41K13
30 amp, 2 pole 17K70
35 amp, 2 pole 72K07
40 amp, 2 pole 49K14
45 amp, 2 pole 17K71
50 amp, 2 pole 41K12
60 amp, 2 pole 17K72

Page 13
Heat Section Installation
WARNING
Before installing or servicing unit, be sure
ALL power to the unit is OFF. More than one
disconnect switch may be present. Electrical
shock can cause personal injury or death!
Before installing the unit, check information on the unit
rating plate to ensure that the unit meets the job specica-
tion, proper electrical power is available, and that proper
duct clearances are maintained.
NOTE – If installing heat sections at the same time as the
air handler unit, install the electric heat section in the air
handler unit before setting the air handler unit and attach-
ing the plenum.
1 - Shut o󰀨 all power to the air handler unit. More than
one disconnect may be required.
2 - Remove air handler access panel and keep the six
screws to reattach access panel after installing heat
elements.
3 - Disconnect any existing eld supply wires and pull
them out of the air handler. Disconnect and remove
wiring harness and fastener (see gure 4). If not
removed, these items will prevent the heat section’s
base from resting properly in the compartment.
4 - Remove the no-heat seal plate in the air handler
frame (see gure 4).
NOTE – If a small heater is installed in the unit, the in-
staller will need to remove the no-heat plate and break it
apart at the perforations and reinstall the two pieces so
the smaller heater can be installed into the unit.
NO‐HEAT
SEAL PLATE REMOVE SCREWS;
THEN REMOVE
NO-HEAT SEAL
PLATE
SEPARATE CONNECTOR;
DISCARD WIRE HARNESS
WIRE
HARNESS
REMOVE FASTENER SECURING WIRES
IF PRESENT
FIGURE 4. Prepare to Install Heat Element
5 - Slide the electric heat section into the air handler. Be
careful that the heating elements do not rub against
the sheet metal opening when they slide into the
air handler. The mounting holes should then line up
with holes in the air handler control box.
6 - Secure the electric heater assembly into place
with the screws that were removed from the heat
element panel. Install two eld-provided #8 SDST
screws in the front of the electric heater assembly
(see gure 5).
INSTALL SCREWS
REMOVED FROM
THE NO-HEAT
SEAL PLATE.
INSTALL 2 FIELD-PROVIDED SCREWS TO SECURE THE
FRONT OF THE HEATER CIRCUIT BREAKER ASSEMBLY TO
THE FRONT FLANGE OF THE AIR HANDLER.
FIGURE 5. Installing the Heat Element Assembly
7 - The air handler’s access panels have a cover
plate that is fastened with a screw and will need to be
positioned to t either one breaker or two, but do not
install the access panel until all electrical connections
have been completed.
WARNING
Foil face insulation must be cut to eliminate the possibility
for any frayed foil to come in contact with any main or low
voltage connections. Insulation must be kept a minimum
of 1/2" away from any electrical connection.
CHANGING CIRCUIT BREAKER ORIENTATION
The air handler comes from the factory ready for hori-
zontal right hand discharge installation. Always rotate the
breaker so up is the ON position in all orientations. The
circuit breaker orientation change is required by UL 1995,
Article 26.18 (25 September 2005).
1 - Locate the one clip located on the right side
(see arrow) of each breaker (see gure 6). The
clip secures the circuit breaker to the mounting
bracket. Pull the clip to release the breaker from
the mounting bracket and rotate the breaker to the
proper postition.

Page 14
CLIP
BREAKER(S)
MOUNTING
BRACKET
NOTE - There may be only one clip securing
each circuit breaker.
CIRCUIT
BREAKER
FIGURE 6. Circuit Breaker Clip
2 - Install the circuit breaker cover plate.
FIGURE 7. Circuit Breaker Cover Plate
NOTE – If electric heat kit has only one circuit breaker, the
breaker cover plate needs to be moved up and installed
over the opening without the circuit breaker. Fasten the
breaker cover plate to the access panel using the circled
hole in gure 7. If the electric heat kit has two circuit break-
ers, the breaker cover plate is not required.
Electrical Connections
WARNING
Electric shock hazard! - Disconnect all power
supplies before servicing.
Replace all parts and panels before
operating.
Failure to do so can result in death or
electrical shock.
IMPORTANT
USE COPPER CONDUCTORS ONLY
NOTE – Refer to the nameplate on the air handler unit
for minimum circuit ampacity and maximum overcurrent
protection size.
The air handler units are provided with openings to be
used with 1-1/2 inch trade size (1-31/32 inch diameter)
conduit.
If you want a single point power supply, refer to the name-
plate on the single point power supply accessory for min-
imum circuit ampacity and maximum overcurrent protec-
tion size. Select the proper supply circuit conductors in
accordance with tables 310-16 and 310-17 in the National
Electric Code, ANSI/NFPA No. 70 or tables 1 through 4 in
the Canadian Electric Code, Part I, CSA Standard C22.1.
Refer to gure 11 for typical low voltage eld wiring for air
handler/condensing unit and heat pump applications. Fig-
ure 8 is a diagram of the air handler connections and the
heater high-voltage wiring.
1 - Make wiring connections as follows:
Heaters equipped with circuit breakers – Connect
eld power supply wiring to circuit breaker(s). Figure
8 shows L1, L2 and ground (GND) connections for
a 2-breaker conguration.
ON
OFF
60
ON
OFF
60
L1
L2
CIRCUIT 1
L1
L2
CIRCUIT 2
GND 208/240 VOLT FIELD
SUPPLY WIRES
Field Supply
Ground Wires
FIGURE 8. Field Power Supply Wiring
2 - Remove the interface harness from the air handler
unit and connect the 6-pin connector on the heater
assembly to the mating connector on the air handler
unit.
3 - For applications using a two-stage room thermostat
and/or an outdoor thermostat, connect wiring as
shown in gure 8.
Circuit Breaker Cover Installation
1 - Remove any installed patch plates still present.
2 - Remove paper backing from the adhesive around
the perimeter of the back side of the circuit breaker
cover (gure 9).
3 - Position the breaker cover over the air handler
circuit breaker opening.

Page 15
CIRCUIT BREAKER COVER
(BACKSIDE)
REMOVE PAPER COVERING
ADHESIVE BACK
FIGURE 9. Remove Paper Cover
IMPORTANT
Conrm air tight seal between breaker cover and air
handler access panel. Apply a thin silicone bead to the
adhesive back seat to ensure air tight seal.
Failure to seal circuit breaker cover will allow warm
moist air to be pulled into control panel which can create
condensation to form on the circuit breaker and other
electrical components within the control panel.
FIGURE 10. Typical Circuit Breaker Cover Installation
Air Handler Speed Connections
When using the electric heat sections with air handler
units, you must adjust the air handler speed according to
the size of electric heat and air handler unit. Air handler
speed tap for electric heat in upow and horizontal
position is medium. For downow it is high speed.
See specic air handler installation instructions for air
handler speed adjustment procedure and location.
1 - Set the thermostat above room temperature.
2 - Check the heat pump and the heat section for
normal operation.
3 - Set the thermostat to desired setting.
4 - A󰀩x the wiring diagram sticker to air handler scroll,
aligned with circuit breaker unit wiring diagram
sticker.
Conguration Modication
UPFLOW APPLICATION
1 - The air handler must be supported on the bottom
only and set on solid oor or eld-supplied support
frame. Securely attach the air handler to the oor or
support frame.
2 - If installing a unit in an upow application, remove
the horizontal drain pan. IMPORTANT - The
horizontal drain pan is not required in upow
air discharge installations; its removal provides
the best e󰀩ciency and air ow.
3 - Place the unit in the desired location and slope unit
as previously mentioned. Connect return and supply
air plenums as required using sheet metal screws.
4 - Install units that have no return air plenum on a
stand that is at least 14" from the oor. This will
allow proper air return.
HORIZONTAL DRAIN PAN
IMPORTANT! REMOVE PAN
FOR BEST EFFICIENCY
AND AIR FLOW.
UPFLOW
DRAIN PAN
NECTIONS (BOTH
SIDES; USE ONE SIDE
OR OTHER)
HORIZONTAL DRAIN
CONNECTIONS
FIGURE 11. Upow Conguration

Page 16
HORIZONTAL APPLICATION
IMPORTANT
When removing the coil, there is possible danger of
equipment damage and personal injury. Be careful when
removing the coil assembly from a unit installed in right-
or left-hand applications. The coil may tip into the drain
pan once it is clear of the cabinet. Support the coil when
removing it.
WEIVDNEWEIVTNORF
ANGLE IRON OR SHEET
METAL
E
ANCE 4 IN. (102 MM)
MAXIMUM 1/2”
LONG SCREW
AIR FLOW
FIGURE 12. Suspend Horizontal Unit
NOTE – When the unit is installed in horizontal applica-
tions, a secondary drain pan is recommended. Refer to
local codes.
NOTE – This unit may be installed in left- or right-hand air
discharge horizontal applications. Adequate support must
be provided to ensure cabinet integrity. Ensure that there
is adequate room to remove service and access panels if
installing in the horizontal position.
LEFT-HAND DISCHARGE
For horizontal left-hand air discharge, the following eld
modications are required. Reference sticker is located on
coil top plate.
1 - Remove access panels and the corrugated padding
between the blower and coil assembly. Discard the
corrugated padding.
2 - Pull the coil assembly from unit. Pull o󰀨 the
horizontal drain pan.
3 - Remove the drain plugs from back drain holes on
horizontal drain pan and reinstall them on front holes.
IMPORTANT
After removal of drain pan plug(s), check drain hole(s)
to verify that drain opening is fully open and free of any
debris. Also check to make sure that no debris has fallen
into the drain pan during installation that may plug up the
drain opening.
4 - Rotate drain pan 180º front-to-back and install it on
the opposite side of the coil.
5 - Remove screws from top cap.
6 - Remove plastic plug from left hole on coil front end
seal and reinstall plug in back hole.
90º
BEND
CABINET
SUPPORT
COIL SHOWN IN UPLOAD POSITION FOR EASY CONVERSION
TOP CAP SCREWS
DRAIN PAN
RE
INSTALLED
HERE
DRAIN PAN
SHIPPING
LOCATION
TOP CAP ROTATED TO
CORRECT POSITION
———— DRAIN PLUGS ————
REINSTALLED HERE REMOVED FROM HERE
BACK COIL END SEAL
TOP
CAP
90º
BEND
ALIGN HOLES WITH
HOLES IN COIL END
PLATE. STARTING WITH
THE ROUND HOLES ON
THIS END.
FIGURE 13. Field Modication for
Left-Hand Discharge
7 - Rotate top cap 180º front-to-back and align with
unused screw holes. Holes must align with front
and back coil end plates. The top cap has a 45º
bend on one side and a 90º bend on the other.
The 90º bend must be on the same side as the
horizontal drain pan as illustrated in gure 13.
FIGURE 14. Left-Hand Discharge Conguration
NOTE – Be very careful when reinstalling the screws into
the coil end plate engaging holes. Misaligned screws may
damage the coil.
8 - From the upow position, ip cabinet 90º to the left
and set into place. Replace blower assembly. See
gure 14 for orientation.
9 - Knock out drain seal plate from access door. Secure
plate to cabinet front ange with screw provided.

Page 17
10 - Flip access door and replace it on the unit.
11 - Set unit so that it is sloped toward the drain pan end
of the unit. See sloping section gure 17. Connect
return and supply air plenums as required using
sheet metal screws.
12 - If suspending the unit, it must be supported along the
entire length of the cabinet. If using chain or strap,
use a piece of angle iron or sheet metal attached to
the unit (either above or below) so that the full length
of the cabinet is supported. Use securing screws no
longer than 1/2ʺ to avoid damage to coil or lter, as
illustrated in gure 12. Connect return and supply
air plenums as required using sheet metal screws.
RIGHT-HAND DISCHARGE
1 - Determine which plugs are required for drain line
connections.
2 - With access door removed, remove drain line plugs
to install drain lines.
3 - Set unit so that it is sloped toward the upow drain
pan end of the unit and level from front to back of
unit (see gure 15).
4 - The horizontal conguration is shown in gure 15.
Drains
AIR FLOW
PLUGS
RIGHT‐HAND DRAINS
FIGURE 15. Right-Hand Discharge Conguration
5 - If the unit is suspended, the entire length of the
cabinet must be supported. If you use a chain or
strap, use a piece of angle iron or sheet metal
attached to the unit (either above or below) to
support the length of the cabinet. Use securing
screws no longer than 1/2 inch to avoid damaging
the coil or lter. See gure 12. Use sheet metal
screws to connect the return and supply air plenums
as required.
DOWNFLOW APPLICATION
NOTE – If downow application is required, separately or-
der kit number Y9658 (-024 through -030) or Y9659 (-036
through -042) .Use the installation instruction 507797-01
provided with the downow kit. Also use metal or class I
supply and return air plenums. Figure 16 shows proper
orientation.
IMPORTANT
If electric heat section with circuit breakers (ECBA25) is
installed in a CBA25UHE unit in a downow application,
the circuit breakers must be rotated 180° to the UP
position. See ECBA25 installation instructions for more
details.
HORIZONTA L DRAIN PAN
(REMOVE FROM UNIT)
UPFLOW /
DOWNFLOW
DRAIN PAN
FIGURE 16. Downow Discharge Position
Brazing Connections
WARNING
Polyol ester (POE) oils used with HFC-410A refrigerant
absorb moisture very quickly. It is very important that the
refrigerant system be kept closed as much as possible.
DO NOT remove line set caps or service valve stub caps
until you are ready to make connections.
WARNING
Danger of re. Bleeding the refrigerant
charge from only the high side may result
in pressurization of the low side shell and
suction tubing. Application of a brazing torch
to a pressurized system may result in ignition
of the refrigerant and oil mixture. Check the
high and low pressures before applying heat.
IMPORTANT
To prevent the build-up of high levels of nitrogen when
purging, it must be done in a well-ventilated area. Purge
low-pressure nitrogen (1 to 2 psig) through the refrigerant
piping during brazing. This will help to prevent oxidation
and the introduction of moisture into the system.

Page 18
WARNING
Danger of explosion!
Can cause equipment damage, injury, or
death.
When using a high pressure gas such as
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).
CAUTION
Brazing alloys and ux 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 ux.
WARNING
When using a high pressure gas such as
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).
TABLE 2. CBA25UHE Refrigerant Connections and
Line Set Requirements
Model Liquid
Line
Vapor
Line L15 Line Sets
-024 3/8ʺ
(10mm)
3/4ʺ
(19mm) L15 line set sizes are
dependant on unit
match-up. See Product
Specications (EHB) for
outdoor unit to determine
correct line set sizes
-030
-036
3/8ʺ
(10mm)
3/4ʺ
(19mm)
-042 3/8ʺ
(10mm)
7/8"
(22mm)
NOTE - Some applications may require a eld-provided 7/8ʺ
to 1-1/8ʺ adapter.
NOTE - When installing refrigerant lines longer than 50
feet, see the Lennox Refrigerant Piping Design and Fab-
rication Guidelines, CORP. 9351-L9, or contact Lennox
Technical Support Product Applications for assistance.

Page 19
REMOVE ACCESS PANEL
A
REMOVE RUBBER PLUG FROM BOTH LIQUID
AND SUCTION LINES
B
USE A WET RAG TO PROTECT CTXV
SENSING BULB WHEN BRAZING
SUCTION LINE CONNECTIONS.
C
NITROGEN
HIGH
LOW
EITHER REMOVE OR PUSH PIPE WRAPPING BACK
THROUGH HOLE IN PIPING PLATE BEFORE LINE
SET CONNECTION AND BRAZING.
D
ECONNECT PIPES
FCONNECT GAUGES AND
START NITROGEN FLOW
GPLACE A WET RAG AGAINST PIPING
PLATE AND AROUND THE SUCTION
LINE CONNECTION. A
HBRAZE CONNECTION. ALLOW PIPE TO
COOL BEFORE REMOVING WET RAG
FROM CTXV SENSING BULB AND PIPING
PANEL AREA.
IREPEAT PREVIOUS PROCEDURE FOR LIQUID
LINE.
NOTE — REFER TO OUTDOOR UNIT INSTALLATION INSTRUCTIONS
FOR REFRIGERANT PIPING SIZE REQUIREMENTS .
NOTE — REFRIGERANT LINE SETS
SHOULD BE ROUTED TO ALLOW
FILTER ACCESSIBILITY.
NOTE — CBA25UHE SERIES UNITS USE NITROGEN OR DRY AIR
AS A HOLDING CHARGE. IF THERE IS NO PRESSURE WHEN
THE RUBBER PLUGS ARE REMOVED, CHECK THE COIL FOR
LEAKS BEFORE INSTALLING.
REFER TO INSTRUCTIONS PROVIDED WITH OUTDOOR UNIT FOR
LEAK TESTING, EVACUATING AND CHARGING PROCEDURES
FLOW REGULATED NITROGEN (AT 1 TO 2 PSIG)
THROUGH THE REFRIGERATION GAUGE SET INTO THE
VALVE STEM PORTCONNECTION ON THE OUTDOOR
UNIT LIQUID LINE SER VICE VALV E AND OUT OF THE
VALVE STEM PORT CONNECTION ON THE SUCTION
SERVICE VALVE.
PIPING
PLATE
NOTE - Use silver alloy brazing rods with five or six percent
minimum silver alloy for copper-to-copper brazing, 45
percent alloy for copper-to-brass and copper-to-steel
brazing.
PLEASE READ IMPORTANT ISSUES CONCERNING BRAZING
OPERATIONS BEFORE PROCEEDING.
FIGURE 17. Brazing Connections

Page 20
Installing the Condensate Drain
IMPORTANT
On units of this type, where the blower “draws” rather than “blows” air through the coil, traps must be installed in the
condensate drain lines (primary and auxiliary, if used). Traps prevent the blower from drawing air through the drain lines
into the air supply.
ABOVE
FINISHED
SPACE?
OVERFLOW DRAIN LINE
ALWAYS RUN AN OVERFLOW DRAIN LINE. IF NOT POSSIBLE TO
ROUTE OVERFLOW DRAIN LINE, INSTALL LOW VOLTAGE
OVERFLOW SWITCH KIT. WIRE KIT TO SHUT DOWN
COMPRESSOR PER INSTRUCTIONS.
NO
YES
LENNOX #
X3169 CLEAN OUT
VENT
PRESS IN
(DO NOT GLUE)
VENT MUST EXTEND
ABOVE HEIGHT OF
COIL DRAIN PAN BY
TWO INCHES (51MM)
1” X 3/4” X 3/4”
REDUCING
TEE WITH
PLUG
LENNOX1P-TRAP
49P66, J-TRAP #
91P90 OR ANY
PVC SCH 40 P- OR
J-TRAP 3/4”
OVERFLOW
DRAIN
AIR HANDLER DRAIN PAN
WHEN A COIL IS LOCATED ABOVE A FINISHED SPACE, A
3/4” (19.1MM) SECONDARY DRAIN LINE MUST BE:
CONNECTED TO SECONDARY DRAIN PAN
OR
CONNECTED TO THE OVERFLOW DRAIN OUTLET OF
THE AIR HANDLER DRAIN PAN.
TRAPS MUST BE DEEP ENOUGH TO OFFSET MAXIMUM STATIC DIFFERENCES —
GENERALLY, TWO INCHES (51MM).
DRAIN LINE SHOULD
SLOPE A MINIMUM OF
ONE INCH PER 10
FEET (25MM PER 3
METERS)
NOTE — WHEN A AIR HANDLER IS LOCATED
ABOVE A FINISHED SPACE THE SECONDARY
DRAIN PAN MUST HAVE A LARGER FOOTPRINT
THAN THE AIR HANDLER.
MAIN
DRAIN
TO APPROVED
DRAIN
FOR NEGATIVE PRESSURE COILS (BLOWER
AFTER COIL) TRAPS ARE REQUIRED ON ALL
DRAIN LINES CONNECTED TO COIL.
COMPACT OVERFLOW SWITCH WITH 3/4” FEMALE SLIP INLET
AND MALE ADAPTER, TWO PART DESIGN FOR USE WHERE
OBSTRUCTIONS PREVENT DIRECT THREADING
SECONDARY
DRAIN PAN
2”
(51MM)
TRAP DEPTH
1LENNOX P-TRAP 49P66 REQUIRES A LARGER INSTALLATION SPACE THAN THE J-TRAP 91P90.
2PIPE NIPPLE PROVIDED IN BAG ASSEMBLY - SCH 80, 3/4” I. D. X 5” - 34K7401 (1): CUT THE PIPE IN HALF AND USE IT TO ROUTE THE MAIN DRAIN.
FIGURE 18. Typical Main and Overow Drain Installations
IMPORTANT
After removal of drain pan plug(s), check drain hole(s)
to verify that drain opening is fully open and free of any
debris. Also check to make sure that no debris has fallen
into the drain pan during installation that may plug up the
drain opening.
1 - Remove the appropriate drain knockouts. If
necessary, remove the indoor coil assembly from
the cabinet.
2 - Connect primary drain line connection to the primary
drain pan connection. The primary drain connection
is ush with the bottom of the inside of the pan.
Secondary connection is raised above the bottom
of the inside of the pan.
NOTE – When making drain tting connections to the
drain pan, hand tighten the tting and use a thread seal-
ant. Over-tightening the ttings can split connections on
the drain pan.
3 - If the auxiliary drain line is to be used, remove
the plug and route the drain line so that water
draining from the outlet will be easily noticed by
the homeowner. The auxiliary drain line does not
require venting or a trap. Refer to local codes.
4 - After removal of drain pan plugs, check the drain
port to see if holes have been drilled. If not drilled,
use a 19/32” bit to drill out the primary drain hole;
use a 3/8” drill bit for the secondary drain hole.
Remove all drill shavings.
5 - Make sure drain ports and drain pan are free of all
debris.