Lennox CBX32MV Series User manual

Page 1 2002 Lennox Industries Inc.
Corp. 0206−L3 CBX32MV
Service Literature Revised 02−2010
CBX32MV (HFC−410A) SERIES UNITS
TABLE OF CONTENTS
Introduction 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Model Number Identification.. 2. . . . . . . . . . . . . . . . . . .
Specifications / Electrical Data 2. . . . . . . . . . . . . . . . . .
Blower Performance 4. . . . . . . . . . . . . . . . . . . . . . . . . . .
Parts Arrangement 10. . . . . . . . . . . . . . . . . . . . . . . . . . . .
I− Application 11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
II− Unit Components 11. . . . . . . . . . . . . . . . . . . . . . . . . . .
III− Troubleshooting the Variable Speed Motor 15. . . . .
IV− Optional Electric Heat 17. . . . . . . . . . . . . . . . . . . . . . .
V− Optional Humidity Control 23. . . . . . . . . . . . . . . . . . . .
VI− Configuration Modifications 30. . . . . . . . . . . . . . . . . .
VII− Start Up Operation 34. . . . . . . . . . . . . . . . . . . . . . . . .
VIII− Operating Characteristics 35. . . . . . . . . . . . . . . . . .
XI− Maintenance 35. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
X− Wiring and Operation Sequence 36. . . . . . . . . . . . . .
Introduction
The CBX32MV is a high efficiency residential split system
blower/coil featuring a variable speed motor controlled by an
electronic blower drive control (BDC).
CBX32MV series units are designed to be matched with
Lennox two-speed or single-speed HFC−410A condensing
units and heat pumps. Several models are available in sizes
ranging from 1.5 through 5 tons. All units are equipped with
factory installed check and expansion valve for cooling or heat
pump applications.
Electric heat is available in several voltages and KW sizes,
and can be field installed in the cabinet.
Some CBX32MV applications may include the optional
Lennox ComfortSense®7000, SignatureStattor
Efficiency Plus Comfort Management Control (CCB1). The
purpose of both controls is to vary indoor blower speed in
response to indoor dehumidification demand. When a
two-speed outdoor unit is used, compressor speed can
also be controlled by the SignatureStat or CCB1 in
response to indoor dehumidification demand.
Information contained in this manual is intended for use by
experienced HVAC service technicians only. All
specifications are subject to change. Procedures outlined
in this manual are presented as a recommendation only
and do not supersede or replace local or state codes.
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 discon-
nect switch(es). Unit may have multiple
power supplies.
ELECTROSTATIC DISCHARGE (ESD)
Precautions and Procedures
CAUTION
Electrostatic discharge can affect electronic
components. Take precautions during unit instal-
lation and service to protect the unit’s electronic
controls. Precautions will help to avoid control
exposure to electrostatic discharge by putting
the unit, the control and the technician at the
same electrostatic potential. Neutralize electro-
static charge by touching hand and all tools on an
unpainted unit surface before performing any
service procedure.

Page 2
Model Number Identification
Refrigerant Type
X = R−410A
230CB 32 036
−05
Series
Nominal Cooling Capacity
018/024 = 1.5 to 2 tons (5.3 to 7 kW)
024/030 = 2 to 2.5 tons (7 to 8.8 kW)
036 = 3 tons (10.6 kW)
048 = 4 tons (14.1 kW)
060 = 5 tons (17.6 kW)
068 = 5+ tons (17.6+ kW)
Minor Revision Number
Configuration
MV = Multi−Position, Variable
speed blower motor
−
X
Voltage
230 = 208/230V−60hz−1ph
−−
6
Refrigerant Metering Device
2 = Fixed Orifice
3 = TXV − Bleedport (indoor unit)
4 = TXV − Non−bleedport (indoor unit)
5 = TXV − Non−bleedport (outdoor unit)
6 = TXV − R−410A Non−bleedport (indoor unit)
MV
Unit Type
CB = Air Handler
Specifications
General Data Model Number CBX32MV-018/024 CBX32MV-024/030 CBX32MV-036
Nominal cooling capacity − tons (kW) 1.5 − 2 (5.3 − 7) 2 − 2.5 (7 − 8.8) 3 (10.6)
Refrigerant R−410A R−410A R−410A
Connections
in. (mm)
Suction (vapor) line − sweat 5/8 (15.8) 3/4 (19) 3/4 (19)
Liquid line − sweat 3/8 (9.5) 3/8 (9.5) 3/8 (9.5)
Condensate drain (fpt) (2) 3/4 (19) (2) 3/4 (19) (2) 3/4 (19)
Indoor
Coil
Net face area − ft.2(m2)3.56 (0.33) 4.44 (0.41) 5.0 (0.46)
Tube outside diameter − in. (mm) 3/8 (9.5) 3/8 (9.5) 3/8 (9.5)
Number of rows 3 3 3
Fins per inch (fins per m) 12 (472) 12 (472) 12 (472)
Blower Data Wheel nominal diameter x width − in. (mm) 10 x 7 (279 x 178) 10 x 8 (279 x 203) 10 x 8 (279 x 203)
Motor output − hp (W) 1/2 (373) 1/2 (373) 1/2 (373)
Filters 1Number and size − in. (1) 15 x 20 x 1 (1) 20 x 20 x 1 (1) 20 x 22 x 1
mm 381 x 508 x 25 508 x 508 x 25 508 x 559 x 25
Shipping Data − 1 Package lbs. (kg) 126 (57) 152 (69) 183 (83)
ELECTRICAL DATA
Voltage − phase − 60hz 208/230V−1ph 208/230V−1ph 208/230V−1ph
2Maximum overcurrent protection (unit only) 15 15 15
Minimum circuit ampacity (unit only) 5 5 5

Page 3
Specifications
General Data Model Number CBX32MV-048 CBX32MV-060 CBX32MV-068
Nominal cooling capacity − tons (kW) 4 (14.1) 5 (17.6) 5+ (17.6+)
Refrigerant R−410A R−410A R−410A
Connections
in. (mm)
Suction (vapor) line − sweat 7/8 (22.2) 1-1/8 (28) 1-1/8 (28)
Liquid line − sweat 3/8 (9.5) 3/8 (9.5) 3/8 (9.5)
Condensate drain (fpt) (2) 3/4 (19) (2) 3/4 (19) (2) 3/4 (19)
Indoor
Coil
Net face area − ft.2(m2)7.22 (0.67) 7.22 (0.67) 7.77 (0.72)
Tube outside diameter − in. (mm) 3/8 (9.5) 3/8 (9.5) 3/8 (9.5)
Number of rows 3 3 3
Fins per inch (fins per m) 12 (472) 12 (472) 12 (472)
Blower Data Wheel nominal diameter x width − in. (mm) 12 x 9 (305 x 229) 12 x 9 (305 x 229) 15 x 9 (381 x 229)
Motor output − hp (W) 1 (746) 1 (746) 1 (746)
Filters 1Number and size − in. (1) 20 x 24 x 1 (1) 20 x 24 x 1 (1) 20 x 25 x 1
mm 508 x 610 x 25 508 x 610 x 25 508 x 635 x 25
Shipping Data − 1 Package − lbs. (kg) 212 (96) 212 (96) 244 (111)
ELECTRICAL DATA
Voltage − phase − 60hz 208/230V−1ph 208/230V−1ph 208/230V−1ph
2Maximum overcurrent protection (unit only) 20 20 20
Minimum circuit ampacity (unit only) 11 11 11
Optional CIRCUIT BREAKER KITS − Must Be Ordered Extra
Amperage 25 30 35 40 45 50 60
Single Phase 23M58 23M59 23M60 23M61 23M62 23M63 23M64
Three Phase − − − 23M65 − − − 23M66 23M67 23M68 23M69

Page 4
Blower Data
CBX32MV-018/024 BLOWER PERFORMANCE
0 through 0.80 in. w.g. (0 through 200 Pa) External Static Pressure Range
ADJUST"
Jumper
Setting
BDC3 Jumper Speed Positions
HEAT" Speed COOL" Speed
1 2 3 4 1 2 3 4
cfm L/s cfm L/s cfm L/s cfm L/s cfm L/s cfm L/s cfm L/s cfm L/s
+ 715 337 855 405 1000 470 1130 535 465 220 690 325 900 425 1050 495
NORM 670 315 770 365 900 425 1035 490 425 200 620 290 825 390 950 450
− 580 275 700 330 800 375 930 440 385 180 560 265 735 345 850 400
NOTES − The effect of static pressure, filter and electric heater resistance is included in the air volumes listed.
Low speed cooling air volume is 70% of COOL speed setting. Production units September 2005 and later; continuous blower speed for is approximately 38% of
COOL speed setting. Earlier production units continuous blower speed is approximately 50% of COOL speed setting.
Harmony Zone Control applications − Low speed cooling is approximately 250 cfm (118 L/s).
Lennox Harmony IIItZone Control applications − Low speed cooling is 300 cfm (145 L/s)
CBX32MV-018/024 BLOWER MOTOR WATTS AT +" (Plus) BDC3 SETTING (Adjust" Jumper at +" Setting)
BDC3 Jumper
Speed Positions
Motor Watts @ Various External Static Pressures − in. wg. (Pa)
0 (0) 0.1 (25) 0.2 (50) 0.3 (75) 0.4 (100) 0.5 (125) 0.6 (150) 0.7 (175) 0.8 (200)
HEAT" Speed Tap 1 100 113 126 142 154 172 190 206 230
Tap 2 155 176 197 221 237 260 278 295 310
Tap 3 237 260 289 305 314 337 356 373 390
Tap 4 338 361 379 409 433 457 447 426 406
COOL" Speed Tap 1 36 47 61 71 81 95 106 118 135
Tap 2 89 103 118 129 143 163 177 197 207
Tap 3 183 198 229 248 266 290 307 327 343
Tap 4 266 294 315 330 349 373 390 411 401
CBX32MV-018/024 BLOWER MOTOR WATTS AT NORM" BDC3 SETTING (Adjust" Jumper at NORM Setting)
BDC3 Jumper
Speed Positions
Motor Watts @ Various External Static Pressures − in. wg. (Pa)
0 (0) 0.1 (25) 0.2 (50) 0.3 (75) 0.4 (100) 0.5 (125) 0.6 (150) 0.7 (175) 0.8 (200)
HEAT" Speed Tap 1 77 96 106 123 130 150 165 178 201
Tap 2 118 136 154 177 189 212 224 247 265
Tap 3 183 198 224 248 264 284 307 321 343
Tap 4 264 284 300 326 343 367 385 406 390
COOL" Speed Tap 1 30 41 55 62 76 86 94 106 114
Tap 2 71 83 101 113 125 138 156 166 185
Tap 3 137 158 176 199 219 238 254 273 296
Tap 4 211 225 249 272 295 318 331 342 367
CBX32MV-018/024 BLOWER MOTOR WATTS AT −" (Minus) BDC3 SETTING (Adjust" Jumper at −" Setting)
BDC3 Jumper
Speed Positions
Motor Watts @ Various External Static Pressures − in. wg. (Pa)
0 (0) 0.1 (25) 0.2 (50) 0.3 (75) 0.4 (100) 0.5 (125) 0.6 (150) 0.7 (175) 0.8 (200)
HEAT" Speed Tap 1 59 73 89 106 113 130 142 156 173
Tap 2 95 106 118 136 152 171 183 200 215
Tap 3 132 148 171 186 211 225 248 266 284
Tap 4 195 217 242 259 283 302 314 336 349
COOL" Speed Tap 1 27 35 47 59 71 77 88 92 106
Tap 2 57 65 83 94 110 119 134 148 166
Tap 3 110 124 141 157 176 188 213 231 242
Tap 4 148 170 195 207 230 248 272 282 306

Page 5
CBX32MV-024/030 BLOWER PERFORMANCE
0 through 0.80 in. w.g. (0 through 200 Pa) External Static Pressure Range
ADJUST"
Jumper
Setting
BDC3 Jumper Speed Positions
HEAT" Speed COOL" Speed
1 2 3 4 1 2 3 4
cfm L/s cfm L/s cfm L/s cfm L/s cfm L/s cfm L/s cfm L/s cfm L/s
+ 800 380 935 440 1070 505 1210 570 660 310 880 415 1100 520 1320 625
NORM 725 340 850 400 975 460 1100 520 600 285 800 380 1000 470 1200 565
− 655 310 765 360 880 415 990 470 540 255 720 340 900 425 1080 510
NOTES − The effect of static pressure, filter and electric heater resistance is included in the air volumes listed.
Low speed cooling air volume is 70% of COOL speed setting. Production units September 2005 and later; continuous blower speed for is approximately 38% of
COOL speed setting. Earlier production units continuous blower speed is approximately 50% of COOL speed setting.
Harmony Zone III Control applications − Low speed cooling is approximately 300 cfm (145 L/s).
CBX32MV-024/030 BLOWER MOTOR WATTS AT +" (Plus) BDC3 SETTING (Adjust" Jumper at +" Setting)
BDC3 Jumper
Speed Positions
Motor Watts @ Various External Static Pressures − in. wg. (Pa)
0 (0) 0.1 (25) 0.2 (50) 0.3 (75) 0.4 (100) 0.5 (125) 0.6 (150) 0.7 (175) 0.8 (200)
HEAT" Speed Tap 1 65 90 120 145 185 210 240 250 275
Tap 2 95 125 150 185 230 265 310 345 365
Tap 3 140 190 225 250 290 320 350 405 450
Tap 4 215 250 285 315 350 390 440 480 505
COOL" Speed Tap 1 45 60 90 120 140 155 165 185 200
Tap 2 80 110 135 165 205 250 285 315 335
Tap 3 150 195 225 260 295 320 370 425 465
Tap 4 265 315 350 400 440 485 525 555 605
CBX32MV-024/030 BLOWER MOTOR WATTS AT NORM" BDC3 SETTING (Adjust" Jumper at NORM Setting)
BDC3 Jumper
Speed Positions
Motor Watts @ Various External Static Pressures − in. wg. (Pa)
0 (0) 0.1 (25) 0.2 (50) 0.3 (75) 0.4 (100) 0.5 (125) 0.6 (150) 0.7 (175) 0.8 (200)
HEAT" Speed Tap 1 50 75 100 135 155 180 195 215 230
Tap 2 80 105 130 155 200 245 265 295 310
Tap 3 110 150 175 200 235 275 320 350 390
Tap 4 155 205 230 270 290 325 360 405 460
COOL" Speed Tap 1 40 55 80 105 120 130 150 165 180
Tap 2 65 90 120 145 190 210 240 260 285
Tap 3 105 145 175 220 250 285 335 370 405
Tap 4 200 245 275 300 335 385 420 470 515
CBX32MV-024/030 BLOWER MOTOR WATTS AT −" (Minus) BDC3 SETTING (Adjust" Jumper at −" Setting)
BDC3 Jumper
Speed Positions
Motor Watts @ Various External Static Pressures − in. wg. (Pa)
0 (0) 0.1 (25) 0.2 (50) 0.3 (75) 0.4 (100) 0.5 (125) 0.6 (150) 0.7 (175) 0.8 (200)
HEAT" Speed Tap 1 45 65 90 110 130 150 165 190 195
Tap 2 60 85 110 145 175 200 215 235 240
Tap 3 85 105 130 165 210 245 280 305 330
Tap 4 115 145 175 205 230 280 325 370 390
COOL" Speed Tap 1 30 50 70 90 100 115 125 140 165
Tap 2 55 75 100 135 155 185 190 210 225
Tap 3 85 115 135 175 210 255 295 320 345
Tap 4 145 175 215 245 280 325 355 410 450

Page 6
CBX32MV-036 BLOWER PERFORMANCE
0 through 0.80 in. w.g. (0 through 200 Pa) External Static Pressure Range
ADJUST"
Jumper
Setting
BDC3 Jumper Speed Positions
HEAT" Speed COOL" Speed
1 2 3 4 1 2 3 4
cfm L/s cfm L/s cfm L/s cfm L/s cfm L/s cfm L/s cfm L/s cfm L/s
+ 1230 580 1335 630 1445 680 1545 730 1090 515 1225 580 1380 650 1545 730
NORM 1120 530 1215 575 1315 620 1400 660 975 460 1125 530 1275 600 1400 660
− 1010 475 1185 560 1200 565 1265 595 900 425 1000 470 1135 535 1265 595
NOTES − The effect of static pressure, filter and electric heater resistance is included in the air volumes listed.
Low speed cooling air volume is 70% of COOL speed setting (65% COOL speed for production prior to August 2002). Production units September 2005 and later;
continuous blower speed for is approximately 38% of COOL speed setting. Earlier production units continuous blower speed is approximately 50% of COOL
speed setting.
Harmony Zone Control applications − Low speed cooling is approximately 380 cfm (178 L/s).
Lennox Harmony IIItZone Control applications − minimum blower speed is 442 cfm (210 L/s).
CBX32MV-036 BLOWER MOTOR WATTS AT +" (Plus) BDC3 SETTING (Adjust" Jumper at +" Setting)
BDC3 Jumper
Speed Positions
Motor Watts @ Various External Static Pressures − in. wg. (Pa)
0 (0) 0.1 (25) 0.2 (50) 0.3 (75) 0.4 (100) 0.5 (125) 0.6 (150) 0.7 (175) 0.8 (200)
HEAT" Speed Tap 1 220 235 265 290 310 335 360 385 465
Tap 2 285 305 330 355 380 405 430 450 475
Tap 3 345 365 405 430 455 485 515 545 570
Tap 4 470 495 515 530 545 560 575 595 610
COOL" Speed Tap 1 145 165 200 225 250 275 300 325 350
Tap 2 225 245 265 290 320 350 370 395 410
Tap 3 305 325 350 390 420 445 475 505 535
Tap 4 470 495 515 530 545 560 575 595 610
CBX32MV-036 BLOWER MOTOR WATTS AT NORM" BDC3 SETTING (Adjust" Jumper at NORM Setting)
BDC3 Jumper
Speed Positions
Motor Watts @ Various External Static Pressures − in. wg. (Pa)
0 (0) 0.1 (25) 0.2 (50) 0.3 (75) 0.4 (100) 0.5 (125) 0.6 (150) 0.7 (175) 0.8 (200)
HEAT" Speed Tap 1 155 185 215 240 265 285 300 335 355
Tap 2 225 245 270 295 325 345 370 390 415
Tap 3 275 290 315 340 375 400 420 445 465
Tap 4 320 345 375 405 435 460 485 515 540
COOL" Speed Tap 1 120 140 160 190 210 230 255 275 300
Tap 2 160 190 220 240 265 290 320 340 365
Tap 3 255 270 295 320 345 375 400 420 445
Tap 4 320 345 375 405 435 460 485 515 540
CBX32MV-036 BLOWER MOTOR WATTS AT −" (Minus) BDC3 SETTING (Adjust" Jumper at −" Setting)
BDC3 Jumper
Speed Positions
Motor Watts @ Various External Static Pressures − in. wg. (Pa)
0 (0) 0.1 (25) 0.2 (50) 0.3 (75) 0.4 (100) 0.5 (125) 0.6 (150) 0.7 (175) 0.8 (200)
HEAT" Speed Tap 1 120 135 165 185 205 225 245 265 300
Tap 2 140 165 195 215 245 270 300 315 335
Tap 3 185 210 240 265 285 310 330 360 385
Tap 4 245 255 290 310 335 355 380 405 430
COOL" Speed Tap 1 90 110 135 155 180 195 210 230 250
Tap 2 120 140 160 185 215 235 255 275 295
Tap 3 160 190 225 240 275 295 320 350 380
Tap 4 245 255 290 310 335 355 380 405 430

Page 7
CBX32MV-048 AND CBX32MV-060 BLOWER PERFORMANCE
0 through 0.80 in. w.g. (0 Through 200 Pa) External Static Pressure Range
ADJUST"
Jumper
Setting
BDC3 Jumper Speed Positions
HEAT" Speed COOL" Speed
1 2 3 4 1 2 3 4
cfm L/s cfm L/s cfm L/s cfm L/s cfm L/s cfm L/s cfm L/s cfm L/s
+ 1850 875 1960 925 2090 985 2150 1015 1625 765 1820 860 2055 970 2145 1010
NORM 1705 805 1800 850 1900 895 2005 945 1425 670 1625 765 1805 850 2005 945
− 1560 735 1625 765 1720 810 1770 835 1205 570 1375 650 1555 735 1725 815
NOTES − The effect of static pressure, filter and electric heater resistance is included in the air volumes listed.
Low speed cooling air volume is 70% of COOL speed setting (60% of COOL speed for production prior to August 2002). Production units September 2005 and
later;continuous blower speed for is approximately 38% of COOL speed setting. Earlier production units continuous blower speed is approximately 50% of COOL
speed setting.
Harmony Zone Control applications − Low speed cooling is approximately 400 cfm (190 L/s).
Lennox Harmony IIItZone Control applications − minimum blower speed is 442 cfm (210 L/s)
CBX32MV-048 AND CBX32MV-060 BLOWER MOTOR WATTS AT +" (Plus) BDC3 SETTING (Adjust" Jumper at +" Setting)
BDC3 Jumper Speed
Positions
Motor Watts @ Various External Static Pressures − in. wg. (Pa)
0 (0) 0.1 (25) 0.2 (50) 0.3 (75) 0.4 (100) 0.5 (125) 0.6 (150) 0.7 (175) 0.8 (200)
HEAT"
Speed
Tap 1 455 505 540 585 630 665 710 745 780
Tap 2 555 595 645 675 730 780 820 865 895
Tap 3 680 720 770 820 865 900 945 985 1030
Tap 4 730 780 825 870 920 970 1020 1055 1110
COOL"
Speed
Tap 1 300 335 370 360 435 465 500 535 575
Tap 2 425 475 500 545 585 635 670 710 745
Tap 3 625 660 705 755 810 850 885 940 970
Tap 4 700 750 800 845 895 940 990 1030 1080
CBX32MV-048 AND CBX32MV-060 BLOWER MOTOR WATTS AT NORM" BDC3 SETTING (Adjust" Jumper at NORM Setting)
BDC3 Jumper Speed
Positions
Motor Watts @ Various External Static Pressures − in. wg. (Pa)
0 (0) 0.1 (25) 0.2 (50) 0.3 (75) 0.4 (100) 0.5 (125) 0.6 (150) 0.7 (175) 0.8 (200)
HEAT"
Speed
Tap 1 360 385 425 465 495 525 565 600 635
Tap 2 400 440 485 520 555 595 640 670 705
Tap 3 480 520 560 605 640 685 765 785 805
Tap 4 580 625 665 710 760 800 835 875 925
COOL"
Speed
Tap 1 215 235 275 295 330 360 400 430 465
Tap 2 310 335 375 405 440 465 500 530 565
Tap 3 415 445 490 535 565 605 650 675 715
Tap 4 580 610 655 695 740 785 830 870 910
CBX32MV-048 AND CBX32MV-060 BLOWER MOTOR WATTS AT −" (Minus) BDC3 SETTING (Adjust" Jumper at −" Setting)
BDC3 Jumper Speed
Positions
Motor Watts @ Various External Static Pressures − in. wg. (Pa)
0 (0) 0.1 (25) 0.2 (50) 0.3 (75) 0.4 (100) 0.5 (125) 0.6 (150) 0.7 (175) 0.8 (200)
HEAT"
Speed Tap 1 265 305 340 370 410 440 460 505 540
Tap 2 320 350 395 420 450 475 515 545 580
Tap 3 375 410 435 470 515 545 575 610 645
Tap 4 400 435 480 525 555 595 640 670 700
COOL"
Speed Tap 1 140 170 195 215 250 275 300 335 360
Tap 2 200 230 260 285 315 355 385 415 450
Tap 3 280 315 340 380 415 445 465 505 540
Tap 4 375 420 440 475 515 550 575 610 645

Page 8
CBX32MV-068 BLOWER PERFORMANCE
0 through 0.80 in. w.g. (0 Through 200 Pa) External Static Pressure Range
ADJUST"
Jumper
Setting
BDC3 Jumper Speed Positions
HEAT" Speed COOL" Speed
1 2 3 4 1 2 3 4
cfm L/s cfm L/s cfm L/s cfm L/s cfm L/s cfm L/s cfm L/s cfm L/s
[phone] 2090 985 2150 1015 1640 775 1840 870 2075 980 2150 1015
NORM 1760 830 1825 860 1920 905 2030 960 1465 690 1625 765 1800 850 2000 945
−1550 730 1650 780 1725 815 1800 850 1250 590 1390 655 1560 735 1720 810
NOTES − The effect of static pressure, filter and electric heater resistance is included in the air volumes listed.
First stage cooling air volume is 60% of COOL speed setting. Production units September 2005 and later;continuous blower speed for is approximately 38% of
COOL speed setting. Earlier production units continuous blower speed is approximately 50% of COOL speed setting.
Lennox Harmony IIItZone Control applications − minimum blower speed is 442 cfm (210 L/s).
CBX32MV-068 BLOWER MOTOR WATTS AT +" (Plus) BDC3 SETTING (Adjust" Jumper at +" Setting)
BDC3 Jumper Speed
Positions
Motor Watts @ Various External Static Pressures − in. wg. (Pa)
0 (0) 0.1 (25) 0.2 (50) 0.3 (75) 0.4 (100) 0.5 (125) 0.6 (150) 0.7 (175) 0.8 (200)
HEAT"
Speed Tap 1 365 410 455 495 545 610 660 725 790
Tap 2 430 485 540 590 640 690 765 835 865
Tap 3 540 585 635 695 750 800 815 840 865
Tap 4 665 710 755 770 790 810 830 845 870
COOL"
Speed Tap 1 255 290 320 365 415 455 505 550 590
Tap 2 355 390 425 475 515 580 630 695 750
Tap 3 505 565 610 70 715 790 815 845 865
Tap 4 725 745 755 770 790 810 830 850 870
CBX32MV-068 BLOWER MOTOR WATTS AT NORM" BDC3 SETTING (Adjust" Jumper at NORM Setting)
BDC3 Jumper Speed
Positions
Motor Watts @ Various External Static Pressures − in. wg. (Pa)
0 (0) 0.1 (25) 0.2 (50) 0.3 (75) 0.4 (100) 0.5 (125) 0.6 (150) 0.7 (175) 0.8 (200)
HEAT"
Speed Tap 1 310 345 385 425 465 510 560 610 665
Tap 2 345 385 420 460 500 620 615 680 735
Tap 3 385 430 480 525 580 640 695 750 815
Tap 4 475 525 560 615 660 720 785 845 810
COOL"
Speed Tap 1 180 205 240 285 325 365 405 435 480
Tap 2 250 285 320 355 410 455 505 535 585
Tap 3 345 375 415 460 505 560 610 670 735
Tap 4 445 510 560 595 665 725 790 845 865
CBX32MV-068 BLOWER MOTOR WATTS AT −" (Minus) BDC3 SETTING (Adjust" Jumper at −" Setting)
BDC3 Jumper Speed
Positions
Motor Watts @ Various External Static Pressures − in. wg. (Pa)
0 (0) 0.1 (25) 0.2 (50) 0.3 (75) 0.4 (100) 0.5 (125) 0.6 (150) 0.7 (175) 0.8 (200)
HEAT"
Speed Tap 1 215 245 285 325 375 415 460 495 540
Tap 2 255 295 325 370 410 460 510 545 580
Tap 3 295 330 375 395 445 495 555 600 660
Tap 4 335 370 400 445 505 550 600 660 705
COOL"
Speed Tap 1 125 150 170 210 245 270 300 340 370
Tap 2 160 185 225 255 300 335 365 415 450
Tap 3 225 245 280 320 370 420 460 510 545
Tap 4 290 325 355 400 445 490 545 595 650

Page 9
Parts Arrangement
CBX32MV
FIGURE 1
CONTROL BOX
ELECTRIC HEAT
SECTION
BLOWER
COMPARTMENT
COIL
HORIZONTAL
DRAIN PAN
CHECK AND EXPANSION VALVE
(COMPLETE WITH SCREEN)
BLOWER ACCESS
PANEL
COIL ACCESS
PANEL
UPFLOW/DOWNFLOW
DRAIN PAN
FIGURE 2
CBX32MV CONTROL BOX
TERMINAL
STRIP (TB1)
R
W3
W2
W1
G
C
TRANSFORMER
(T1)
SMALL ELECTRIC HEAT
KNOCK OUT FOR
2.5 − 15 kW
BLOWER
RELAY (K20)
LARGE ELECTRIC HEAT
ADDITIONAL KNOCK
OUT FOR
20 − 30 kW
GROUNDING
LUGS
TERMINAL
STRIP
(TB2)
0Y1Y2DS
BDC3 BLOWER
CONTROL (A15)

Page 10
I−APPLICATION
CBX32MV blower coils are designed for R410A
applications only. All major blower coil components
must be matched according to Lennox
recommendations for the unit to be covered under
warranty. Refer to the Engineering Handbook 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 expansion valve for all
applications. It has been installed internally and is accessible if
required.
II−UNIT COMPONENTS
A−Control Box
The CBX32MV control box is shown in figure 2. Line voltage
and electric heat connections are made in the control box.
Optional electric heat fits through an opening located in the
center of the control box. When electric heat is not used,
knockout plates cover the opening. The electric heat control
arrangement is detailed in the electric heat section of this
manual.
B−Terminal Strips (TB1 and TB2)
All CBX32MV units are equipped with two low voltage
terminal strips (TB1 and TB2) located in the control box.
See figure 2. The strips are used for making up all indoor
thermostat wires.
All CBX32MV units have factory installed jumpers
connecting DS to Y1, R to O and Y1 to Y2. These jumpers
will have to be removed in certain unit application. See table
1.
TABLE 1
Application Remove Jumpers
Harmony II, CCB1,
SignatureStattDS to Y1
Heat Pump R to O
Two−Stage Cooling Y1 to Y2
C−Transformer (T1)
All CBX32MV 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.
D−Blower Relay (K20)
All units use SPDT relay to energize the blower motor in
response to heating demand. The relay coil is energized
when the 1st stage electric heat relay closes. When K20 is
energized, its N.O. contacts close to energize jack plug
JP46 pin 2 (located on blower drive control A15). When
JP46−2 is energized, the blower drive control immediately
energizes the blower on heating speed. Heating speed will
override cooling speed. K20−2 will energize the
economizer if used ( refer to wiring diagram.)
FIGURE 3
BLUE
YELLOW
ORANGE
RED
BLACK
240 VOLTS
208 VOLTS
PRIMARY SECONDARY
208 / 240 VOLT TRANSFORMER
CB8
E−Circuit Breaker (CB8)−1 units & Fuse (F1)
All transformers used in the CBX32MV−1 series units are
equipped with internal secondary voltage overcurrent
protection. Each transformer uses a manual re−set circuit
breaker (CB8) located on the transformer. The circuit
breaker is connected in series with the blue secondary
voltage wire and is rated at 3.5 Amps. CBX23MV−2 units
and later are equipped with a fuse (F1) rated at 3 amps. F1
is connected in series with the blue secondary voltage wire
and like CB8 provides overcurrent protection.
F−Plastic Drain Pans
Both upflow/downflow and horizontal drain pans are
provided and installed on the CBX32MV units. The drain
pans are made from fiberglass-filled plastic. The drain hole
is used for right-hand air discharge only, and must be
plugged when the unit is configured for left-hand air
discharge (see page 24 for horizontal left-hand
application). Each pan has a set of connections, one for a
primary drain and one for an auxiliary drain.
G−Coil
All CBX32MV series units have dual slab coils arranged in
an "A" configuration. Each coil has two or three rows of
copper tubes fitted with ripple-edge aluminum fins. A check
and expansion valve complete with screen feeds multiple
parallel circuits through the coils. The coil is designed to
easily slide out of the unit cabinet.
Optional electric heating elements are sequenced so
blower relay K20 operates on a first on/last off basis.
H−Variable Speed Blower Motor (B3)
CBX32MV series units use a single-phase variable-speed
motor. See figure 4. A solid-state controller is attached to
the motor.

Page 11
CBX32MV MOTOR BLOWER HOUSING
MOTOR BLOWER HOUSING
FIGURE 4
CBX32MV BLOWER MOTOR
B3
MOTOR
CONTROLLER
SHAFT
J49
J48
CBX32MV BLOWER MOTOR COMPONENTS
STATOR
(WINDINGS)
OUTPUT
SHAFT
BEARING
ROTOR
ARROW MUST
BE UP
I−BDC3 Blower Control Board (A15)
CFM on the CBX32MV unit is controlled by the BDC3 board
(A15) located in the control box. CFM can be obtained by
positioning jumpers (COOL, HEAT and ADJUST) on the
BDC3 board. The jumpers are labeled 1,2,3, and 4. Each
enables a different air volume. Diagnostic LEDs are
provided as an aid in identifying the unit’s mode of
operation. The LEDs are labeled RUN and CFM. See
figure 5.
BLOWER SPEED ADJUSTMENTS
Diagnostic LEDs
RUN"
RUN indicates there is a demand for the blower motor to
run.
CFM"
CFM LED indicates the CFM the unit is operating according to
the jumper settings. The light flashes once for approximately
every 100 CFM. For example, if the unit is operating at 1000
CFM, CFM LED will flash 10 times. If the CFM is 1150, CFM
LED will flash 11 full times plus one fast or half flash.
At times the light may appear to flicker or glow. This takes
place when the control is communicating with the motor
between cycles. This is normal operation.
The appropriate speed according to application and CFM
need is selected by moving jumper pins.
Jumper Settings
IMPORTANT
Before changing jumper setting, make sure the
motor has completely stopped. Any jumper set-
ting change will not take place while the motor is
running.
Table 2 shows the recommended factory blower speed tap
selections for CBX32MV series units. These settings are
for nominal tonnage match−ups with the CBX32MV. When
matched with other sizes, it is recommended that the CFM
be adjusted to approximately 400 CFM per ton.
TABLE 2
FACTORY BLOWER SPEED TAP SELECTION
UNIT
SPEED TAP SELECTION
COOL" HEAT"
Condensing
Unit
Heat
Pump
*Condensing Unit
with Electric Heat
Only
*Heat Pump
with Electric
Heat
−018/
024
COOL
PIN #3
COOL
PIN
#3
HEAT
PIN #4
HEAT
PIN #4
−024/
−030
COOL
PIN #3
COOL
PIN
#3
HEAT
PIN #4
HEAT
PIN #4
−036 COOL
PIN #3
COOL
PIN
#3
HEAT
PIN #4
HEAT
PIN #4
−048 COOL
PIN #2
COOL
PIN
#2
HEAT
PIN #1
HEAT
PIN #1
−060 COOL
PIN #3
COOL
PIN
#3
HEAT
PIN #1
HEAT
PIN #1
−068 COOL
PIN #3
COOL
PIN
#3
HEAT
PIN #4
HEAT
PIN #4
*Minimum setting for heat.
To change jumper positions, gently pull the jumper off the pins
and place it on the desired set of pins. The following section
outlines the different jumper selections available and
conditions associated with each one. Refer to figure 5 for
identification.
After the CFM for each application has been determined,
the jumper settings must be adjusted to reflect those given
in the blower data tables at the front of this manual. From
the tables determine which row of CFM volumes most
closely matches the desired CFM. Once a specific row has
been chosen (+, NORMAL, or −), CFM volumes from other
rows cannot be used. Below are the descriptions of each of
the jumper selections.

Page 12
BDC3 VARIABLE SPEED CONTROL SELECTIONS
FIGURE 5
JP1 15 PIN PLUG
(BOARD TO MOTOR)
1
2
3
4
1
2
3
4
1
2
3
4
TEST
−
+
NORM
ADJUST HEAT COOL DELAY CFM RUN
24V/1A
ACC
JP1
ACCESSORY RELAY
CONTACTS
(DRIVES OPTIONAL
ACCESSORY
RELAY)
OPERATIONAL
SELECTOR PINS
(Affects both heating
and cooling modes)
DIAGNOSTIC
DS LEDS
HEATING SPEED
SELECTOR PINS
COOLING SPEED
SELECTOR PINS FAN DELAY
SELECTOR PINS
15
11 15
ADJUST"
The ADJUST pins allow the motor to run at normal speed,
approximately 10% higher, or approximately 10% lower than
normal speed. The blower tables give three rows (+,
NORMAL, and −) with their respective CFM volumes. Notice
that the normal adjustment setting for heat speed position #3
is 1315 CFM. The + adjustment setting for that position is
1445 CFM and for the − adjustment setting is 1185 CFM.
After the adjustment setting has been determined, chose the
remainder speed jumper settings from those offered in the
table in that row.
The TEST pin is available to bypass the BDC3 control and
run the motor at approximately 70% to test that the motor is
operational. This is beneficial primarily in troubleshooting.
G must be energized for motor to run.
COOL"
The COOL jumper is used to determine the CFM during
either 1) cooling or 2) heat pump operation without a call for
electric heat. These jumper selections are activated for
cooling when Y2 and DS terminals in the CBX32MV are
energized and for heating when Y2 is energized.
Applications without the Lennox SignatureStattor
EfficiencyPlusTM CCB1 humidity control will provide 70% of
the COOL CFM during first−stage cooling for two−speed
outdoor units. Units built prior to August 2002, will provide
either 60% (−048, −060 series units) or 65% (−036 series
units) of the COOL CFM during first stage cooling for two
stage outdoor units. 100% of COOL speed is provided for
systems with a single−speed outdoor units.
NOTE − For two speed heat pump units blower will operate at
60%, 65% or 70% of COOL CFM. For single speed heat pump
units blower will operate at 100% COOL CFM until
supplemental electric heat is demanded. At that time, the
blower will operate at HEAT speed selected. This arrangement
provides for warmer supply air during heat pump operation
only.
HEAT"
The HEAT jumper is used to determine CFM during a W1
demand for electric heat operation. These jumper
selections are activated when W1 is energized with or
without a Y1 demand for heat pump compressor.
DELAY"
The DELAY jumper is used to set the specific motor fan
mode of operation during cooling. Depending on the
application, one of four fan options may be chosen by
moving the jumper pins to the appropriate set of pins.
Options 1, 2, 3, or 4 will have an increased dehumidification
effect on the system. Option 1 will have the least effect and
option 4 will have the greatest effect.
Applications with the EfficiencyPlus CCB1 humidity
control create different CFM volumes. For example,
during a first−stage cooling call (two−speed outdoor unit)
with no demand from the CCB1, the air volume is 40% of
the COOL jumper selection. For a normal COOL (Pin #2
setting for CBX32MV−036), the CFM is 1125; the reduced
speed is 450 CFM (1125 x 40% = 450). This arrangement
provides for additional dehumidification during standard
first stage cooling. See tables 10 and 11 for various
scenarios concerning use of the CCB1 humidity control
and the CBX32MV series unit.
Applications with the Lennox SignatureStat but no
demand for de−humidification will operate as follows:
during a first−stage cooling call (two−stage outdoor unit),
the air volume is 70% of the COOL jumper selection. For a
normal COOL (Pin #2 setting for CBX32MV−036), the
CFM is 1125; the reduced speed is 788 CFM (1125 x 70% =
788). This arrangement provides for additional
dehumidification during standard first stage cooling. See
tables 12 and 13 for various scenarios concerning use of
the SignatureStat and the CBX32MV series unit.
For applications with Harmonyrzone control, the blower
CFM volume is determined by the Harmony control center.
This speed is not adjustable. See footnotes in the blower
tables (table of contents).

Page 13
CBX32MV units built prior to February 2003
#1 PIN JUMPERED
A−Motor runs at 100% until demand is satisfied.
B− Once demand is met, motor ramps down to off.
OFFOFF
A B
100% CFM
COOLING
DEMAND
#2 PIN JUMPERED
A−Motor runs at 82% for approximately 7−1/2 minutes. If
demand has not been satisfied after 7−1/2 minutes,
B−motor runs at 100% until demand is satisfied.
C− Once demand is met, motor ramps down to off.
OFF
OFF
ABC
82%CFM 100% CFM
COOLING DEMAND
7 1/2 MIN
#3 PIN JUMPERED
A−Motor runs at 50% for 1/2 minute. B−Motor then runs at
82% for approximately 7−1/2 minutes. If demand has not
been satisfied after 7−1/2 minutes. C−Motor runs at 100%
until demand is satisfied. D− Once demand is met, motor
ramps down to off.
A
B
OFF
OFF
C D
1/2 MIN
50% CFM
7 1/2 MIN
82% CFM 100% CFM
COOLING DEMAND
#4 PIN JUMPERED
A−Motor runs at 50% for 1/2 minute. B−Motor then runs at
82% for approximately 7−1/2 minutes. If demand has not
been satisfied after 7−1/2 minutes. C−Motor runs at 100%
until demand is satisfied. D− Once demand is met, motor
runs at 50% for 1/2 minute then E− Motor ramps down to off.
A
B
OFF
OFF
C D
E
1/2 MIN
50% CFM
COOLING DEMAND
7 1/2 MIN
82% CFM
100%
CFM
1/2 MIN
50% CFM
CBX32MV units built February 2003 and later
#1 Pins Jumpered
A− Motor runs at 100% until demand is satisfied.
B− Once demand is met, motor ramps down to stop.
OFFOFF
A B
100% CFM
COOLING
DEMAND
#2 Pins Jumpered
A− Motor runs at 100% until demand is satisfied.
B− Once demand is met, motor runs at 100% for 45*
seconds.
C− Motor ramps down to stop.
OFF
OFF
ABC
100% CFM 100% CFM
(*45 seconds)
COOLING DEMAND
* CB32XMV units date coded prior to 2−2006 will delay 60 seconds
#3 Pins Jumpered
A− Motor runs at 82% for approximately 7−1/2 minutes. If
demand has not been satisfied after 7−1/2 minutes −
B− Motor runs at 100% until demand is satisfied.
C− Once demand is met, motor ramps down to stop.
OFF
OFF
ABC
82%CFM 100% CFM
COOLING DEMAND
7 1/2 MIN
#4 Pins Jumpered
A− Motor runs at 50% for 30 seconds.
B− Motor then runs at 82% for approximately 7−1/2
minutes. If demand has not been satisfied after 7−1/2
minutes,
C− Motor runs at 100% until demand is satisfied.
D− Once demand is met, motor runs at 50% for 30
seconds.
E− Motor ramps down to stop.
A
B
OFF
OFF
C D
E
1/2 MIN
50% CFM
COOLING DEMAND
7 1/2 MIN
82% CFM
100%
CFM
1/2 MIN
50% CFM
III−VARIABLE SPEED MOTOR
TROUBLESHOOTING
DO
•Check motor, controls, wiring and connections
thoroughly before replacing.
•Use proper replacement parts for motor and control
model numbers.
•Keep duct static to a minimum.
•Size equipment properly.
•Check orientation before inserting motor connector.
DON’T
•Automatically assume the motor is bad.
•Locate connectors above 7 and 4 o’clock positions.
•Replace a control or motor number with an
unauthorized replacement.
•Use high pressure drop filters.
•Use restricted returns.
•Oversize systems then compensate with low airflow.
MOISTURE CHECK
•Connectors should point downward.
•Arrange harness with drip loop under motor.
•Check condensate drain plug.
•Check for airflow (too much latent capacity).
•Check for undercharged condition.
•Check for plug leaks in return ducts, cabinet.

Page 14
MOTOR CHECK
Kit #70J11 can be used to check the motor. The kit is
available at the Lennox parts center. If not using the kit,
follow the procedure below. These settings and jumper
placements will bypass the BDC3 control board and
confirm correct motor operation.
Symptom Cause/Procedure
Motor rocks slightly
when starting
This is normal start−up for the variable speed
motor
Motor will not start,
no movement
•Check power at motor
•Check low voltage (24vac R to C) at motor
•Check low voltage connection (G, Y, R, C) at
motor.
•Check for unseated pins on motor harness.
•Test with temporary jumper between R−G.
•Check motor for tight shaft.
•Run moisture check.
Motor rocks, but
won’t start
•Check for loose or compliant motor mount.
•Make sure blower wheel is tight on shaft.
Motor starts, but
varies up and down
or intermittent
•Check line voltage for variation or "sag."
•Check low voltage connections (G, Y, R, C)
at motor
•Check for unseated pins in motor harness.
•Check "DS" on terminal strip for CFM
command
•Check system controls thermostat.
•Perform moisture check.
Motor "Hunts" or
"Puffs" at high CFM
If removing panel or filter reduces "Puffing"
reduce restriction or reduce max airflow.
Stays at low CFM
despite system call
for cool or heat CFM
•Check low voltage thermostat wires and
connections.
•Verify fan is not in delay mode.
•Check "R" missing/not connected to motor.
•Perform motor check.
Stays at high CFM
•Check "R" connection at motor.
•Check fan delay, wait until complete.
•Perform motor check.
Blower will not shut
off
•Current leakage from controls into G, Y or
W?
•Check for Triac switched thermostat or solid
state relay.
Air noise
•Check for proper airflow setting.
•Check/replace filter.
•Use low pressure drop filter.
•Check/correct duct restrictions.
Noisy Blower or
cabinet
•Check for loose blower housing, panels, etc
•If high static causing noise, check for air
whistling through seams in ducts, cabinets or
panels.
•Check cabinet/duct for deformation.
Motor failure has
occurred and
moisture is present
Replace motor and perform moisture check.
*60/65/70% OF COOL SPEED
•Disconnect power to the unit.
•Change delay pin setting on the BDC3 board to #1
•Remove wires from terminal strips in control box.
•Install jumpers between "R" and "Y1" and "R
and "G"
•Turn on power to unit. Blower should operate on
60%, 65% or 70% of cool speed.
•When check is complete disconnect power and
replace delay setting to original position.
*Reduced blower speed for production August 2002 and later
is 70% of COOL speed for ALL model units. Reduced blower
speed for production prior to August 2002 is 65% of COOL for
the −036 units and 60% of COOL for −048 and −060 series
units.
COOL SPEED
•Disconnect power to unit.
•Change delay pin setting on the BDC3 board to #1
•Remove wires from terminal strips in control box.
•Install jumpers between "R" and "Y1", "R" and
"Y2","R" and "DS"and "R" and "G".
•Turn on power to unit. Blower should operate on
cool speed.
•When check is complete disconnect power and
replace delay setting to original position.
HEAT SPEED
•Disconnect power to the unit.
•Change delay pin setting on the BDC3 board to #1
•Remove wires from terminal strips in control box.
•Install jumper between "R" and "W1".
•Turn on power to unit. Blower should operate on
heat speed.
•When check is complete disconnect power and
replace delay setting to original position.
Notes on 5 Pin AC Line Connection
(See Figure 6)
•The motor connects directly to the line.
•Pins 1 & 2 are jumpered in the harness for 115V
operation.
•Make sure power is off before inserting power
connector.
•Plug is polarized.
Notes on 16 Pin Control Connection
(See Figure 6)
•Control functions (G, Y1, Y2) may be active at greater
than .5 x control transformer voltage.
•Do not apply 24vac to either "Out" pin (8 or16).
•High voltage on control pins will destroy motor.
•Make sure pins are fully seated in connector and
housing.
•Verify common connection from transformer (C or B)
to C1, C2 (Pin 1 and Pin 3).
•Once common is verified, test motor by applying
24vac (R) to control pins.
AC Line
AC Line
Gnd
Line 1 and 2 will be
connected for 120 Vac
applications only
Out −
Adjust 
Y1
Delay
Common 2
W/W1
Common 1
Out+
G (fan)
Y/Y2
EM ht/W2
24Vac (R)
Heat
DS/Pwn (Speed)
O (Rev Valve)
Cool
FIGURE 6
Motor Connectors
(Cable Half)
5 Pin Power
connector
16 Pin Control
Connector

Page 15
IV−OPTIONAL ECB29/31 ELECTRIC HEAT
A−Matchups and Ratings
Tables 4, 5 and 6 show all approved CBX32MV to ECB29
matchups and electrical ratings.
B−Electric Heat Components
ECB29 parts arrangement is shown in figures 7 through 10. All
electric heat sections consist of components mounted to the
electric heat vestibule panel and electric heating elements
exposed directly to the air stream. 208/230V electric heat
sections may be equipped with circuit breakers. The circuit
breakers are designated by CB in the model number.
1−Primary(S15) & Secondary(S20) Temperature Limits
Both the primary (S15) and secondary (S20) limits are
located on the electric heat vestibule panel and are
exposed directly to the air stream through an opening in
the panel. The high temperature limits are SPST N.C.
limits with the primary limit being an auto-reset limit and the
secondary limit being a one-time" limit. One-time limits
must be replaced when opened. The limits are factory set
and are not adjustable.
208/230 Volt Electric Heat Sections
Each stage of the 208/230 electric heat is protected
by a primary (S15) and secondary (S20) high
temperature limit. Both S15 and S20 are located in the
same housing. Each stage uses the same style of limits.
Both the primary and secondary limits are wired in series
with a heat element. When either S15 or S20 opens, the
corresponding heat element is de-energized. All
other heating elements remain energized. The primary
high temperature limit opens at 150_F + 5_F (65.5_C +
2.8_C) on a temperature rise and automatically resets
at 110_F + 9_F (43.3_C + 5.0_C) on a temperature
fall. The secondary high temperature limit opens at
333_F + 10_F (167.2_C + 5.6_C) on a temperature
rise. If the secondary limit opens it must be replaced.
2−Electric Heat Sequencer Relays
(K32, K33, K34, K35, and K116) (208/230 volt only)
Relays K32, K33, K34, K35 and K116 are N.O.
sequencer relays with a resistive element for a coil
and a bi-metal disk which actuates the contacts. The
relays are located on the electric heat vestibule panel and
are energized by a 24V heating demand (W1, W2, and
W3) via jack/plug 2 (J2), which is used to connect electric
heat to the blower coil control circuit. When energized, the
internal resistance heats the bi-metal disk causing the
contacts to close. When the relay is de-energized, the
disk cools and the contacts open. The relays
energize different stages of heat, as well as the
blower. The blower is always first on and last off.
3−Circuit Breaker (CB1, CB2, and CB3)
(208/230 volt only)
Line voltage connections are made to circuit breakers
CB1, CB2, and CB3 in the electric heat sections with
circuit breakers (designated by CB in the model numbers).
Table 3 shows the amperage rating for each circuit
breaker used. Single-phase electric heat uses two pole
circuit breakers; while three-phase electric heat uses three
pole circuit breakers.
TABLE 3
ECB29 CIRCUIT BREAKERS
UNIT CB1
AMPS
CB2
AMPS
CB3
AMPS
ECB29-5CB-1 (P) 30 AMP −−− −−−
ECB29-8CB-1 (P) 50 AMP −−− −−−
ECB29-12.5CB-1 (P) 25 AMP 50 AMP −−−
ECB29-15CB-1 (P) 30 AMP 60 AMP −−−
ECB29-25CB-1 (P) 50 AMP 50 AMP 50 AMP
ECB29-30CB-1 (P) 60 AMP 60 AMP 60 AMP
ECB29-15CB-1 (Y) 60 AMP −−− −−−
ECB29-20CB-1 (Y) 40 AMP 35 AMP −−−
ECB29-25CB-1 (Y) 50 AMP 35 AMP −−−
Note: Do not remove patch plate or insulation on units
without circuit breakers!!
4−Terminal Strip (TB2) 208/230 volt only)
For the electric heat sections without circuit breakers or
fuses, line voltage connections are made to terminal strip
TB2. The terminal strip is located in the lower left corner of
the electric heat vestibule panel. Single-phase electric
heat uses two pole terminal strips; while three-phase
electric heat uses three pole terminal strips.
5−Heating Elements (HE1 through HE6)
Heating elements are composed of helix wound bare
nichrome wire exposed directly to the air stream. The
elements are supported by insulators mounted to the wire
frame. For single phase applications, one element is
used per stage. Each stage is energized
independently by the corresponding relay located
on the electric heat vestibule arranged in a three
phase delta. Once energized, heat transfer is
instantaneous. High temperature protection is
provided by primary and secondary high
temperature limits.

Page 16
TABLE 4 − ELECTRIC HEAT DATA
SINGLE PHASE ELECTRIC HEAT CBX32MV−018/024 CBX32MV−024/030
Model Number
No. of
Steps
Volts
Input
kW
Input
1Btuh
Input
2Blower
Motor
Full
Load
Amps
3Minimum
Circuit
Ampacity
5Maximum
Overcurrent
Protection
2Blower
Motor
Full
Load
Amps
3Minimum
Circuit
Ampacity
5Maximum
Overcurrent
Protection
Circuit Circuit
121 2
2.5 kW
4 lbs.
ECB29-2.5 (28K30)
Terminal Block
1208 1.9 6,400 4.3 17 15 − − − − − − − − − − − − − − −
220 2.1 7,200 4.3 17 20 − − − − − − − − − − − − − − −
230 2.3 7,800 4.3 18 20 − − − − − − − − − − − − − − −
240 2.5 8,500 4.3 18 20 − − − − − − − − − − − − − − −
5 kW
4 lbs.
ECB29-5 (28K31)
Terminal Block
ECB29-5CB (28K32)
30A Circuit breaker
1208 3.8 12,800 4.3 28 30 4.3 28 − − − 30 − − −
220 4.2 14,300 4.3 31 35 4.3 31 − − − 35 − − −
230 4.6 15,700 4.3 31 35 4.3 31 − − − 35 − − −
240 5.0 17,100 4.3 31 35 4.3 31 − − − 35 − − −
6 kW
4 lbs.
ECB29-6 (47L22)
Terminal Block
ECB29-6CB (47L23)
35A Circuit breaker
1208 4.5 15,400 4.3 32 35 4.3 32 − − − 35 − − −
220 5.0 17,100 4.3 37 40 4.3 37 − − − 40 − − −
230 5.5 18,800 4.3 37 40 4.3 37 − − − 40 − − −
240 6.0 20,500 4.3 37 40 4.3 37 − − − 40 − − −
8 kW
5 lbs.
ECB29-8 (28K33)
Terminal Block
ECB29-8CB (28K34)
45A Circuit breaker
2208 6.0 20,500 4.3 41 45 4.3 41 − − − 45 − − −
220 6.7 22,900 4.3 47 50 4.3 47 − − − 50 − − −
230 7.3 25,100 4.3 47 50 4.3 47 − − − 50 − − −
240 8.0 27,300 4.3 47 50 4.3 47 − − − 50 − − −
9 kW
5 lbs.
ECB29−9CB (10L11)
50A Circuit breaker
ECB29EH-9CB (91K67)
50A Circuit breaker
2208 6.8 23,100 4.3 46 50 4.3 46 − − − 50 − − −
220 7.6 25,800 4.3 52 60 4.3 52 − − − 60 − − −
230 8.3 28,200 4.3 52 60 4.3 52 − − − 60 − − −
240 9.0 30,700 4.3 52 60 4.3 52 − − − 60 − − −
10 kW
6 lbs.
ECB29−10 (28K35)
Terminal Block
ECB29-10CB (28K36)
60A Circuit breaker
2208 7.5 25,600 4.3 51 60 − − − − − − − − − − − − − − −
220 8.4 28,700 4.3 53 60 − − − − − − − − − − − − − − −
230 9.2 31,400 4.3 55 60 − − − − − − − − − − − − − − −
240 10.0 34,100 4.3 58 60 − − − − − − − − − − − − − − −
12.5 kW
10 lbs.
ECB29-12.5CB (28K37)
(1) 25A & (1) 50A Circuitbreaker
ECB29EH-12.5CB (91K68)
(1) 25A & (1) 50A Circuitbreaker
3208 9.4 32,000 − − − − − − − − − 4.3 24 31 25 445
220 10.5 35,800 − − − − − − − − − 4.3 27 35 30 50
230 11.5 39,200 − − − − − − − − − 4.3 27 35 30 50
240 12.5 42,600 − − − − − − − − − 4.3 27 35 30 50
15 kW
12 lbs.
ECB29-15CB (28K38)
(1) 30A & (1) 60A Circuit breaker
ECB29EH-15CB (91K69)
(1) 30A & (1) 60A Circuit breaker
3208 11.3 38,400 − − − − − − − − − 4.3 28 37 30 450
220 12.6 43,000 − − − − − − − − − 4.3 31 42 35 60
230 13.8 47,000 − − − − − − − − − 4.3 31 42 35 60
240 15.0 51,200 − − − − − − − − − 4.3 31 42 35 60
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.
2Amps shown are for blower motor only.
3Refer to National or Canadian Electrical Code manual to determine wire, fuse and disconnect size requirements. Use wires suitable for at least 167°F (75_C).
4Bold text indicates that the circuit breaker on CB" circuit breaker models must be replaced with size noted.
5HACR type circuit breaker or fuse.

Page 17
TABLE 5 − ELECTRIC HEAT DATA
SINGLE PHASE ELECTRIC HEAT CBX32MV−036
Model Number
No.
of
Steps
Volts
Input
kW
Input
1Btuh
Input
2Blower
Motor Full
Load Amps
3Minimum
Circuit
Ampacity
5Maximum
Overcurrent Protection
Circuit Circuit
1212
5 kW
4 lbs.
ECB29-5 (28K31)
Terminal Block
ECB29-5CB (28K32)
30A Circuit breaker
1208 3.8 12,800 4.3 28 − − − 30 − − −
220 4.2 14,300 4.3 31 − − − 35 − − −
230 4.6 15,700 4.3 31 − − − 35 − − −
240 5.0 17,100 4.3 31 − − − 35 − − −
6 kW
4 lbs.
ECB29-6 (47L22)
Terminal Block
ECB29-6CB (47L23)
35A Circuit breaker
1208 4.5 15,400 4.3 32 − − − 35 − − −
220 5.0 17,100 4.3 37 − − − 40 − − −
230 5.5 18,800 4.3 37 − − − 40 − − −
240 6.0 20,500 4.3 37 − − − 40 − − −
8 kW
5 lbs.
ECB29-8 (28K33)
Terminal Block
ECB29-8CB (28K34)
45A Circuit breaker
2208 6.0 20,500 4.3 41 − − − 45 − − −
220 6.7 22,900 4.3 47 − − − 50 − − −
230 7.3 25,100 4.3 47 − − − 50 − − −
240 8.0 27,300 4.3 47 − − − 50 − − −
9 kW
5 lbs.
ECB299CB (10L11)
50A Circuit breaker
ECB29EH-9CB (91K67)
50A Circuit breaker
2208 6.8 23,100 4.3 46 − − − 50 − − −
220 7.6 25,800 4.3 52 − − − 60 − − −
230 8.3 28,200 4.3 52 − − − 60 − − −
240 9.0 30,700 4.3 52 − − − 60 − − −
12.5 kW
10 lbs.
ECB29-12.5CB (28K37)
(1) 25A & (1) 50A Circuitbreaker
ECB29EH-12.5CB (91K68)
(1) 25A & (1) 50A Circuitbreaker
3208 9.4 32,000 4.3 24 31 25 445
220 10.5 35,800 4.3 27 35 30 50
230 11.5 39,200 4.3 27 35 30 50
240 12.5 42,600 4.3 27 35 30 50
15 kW
12 lbs.
ECB29-15CB (28K38)
(1) 30A & (1) 60A Circuit breaker
ECB29EH-15CB (91K69)
(1) 30A & (1) 60A Circuit breaker
3208 11.3 38,400 4.3 28 37 30 450
220 12.6 43,000 4.3 31 42 35 60
230 13.8 47,000 4.3 31 42 35 60
240 15.0 51,200 4.3 31 42 35 60
20 kW
19 lbs.
ECB29-20CB (11L31)
(1) 50A & (1) 60A Circuit breaker
ECB29EH-20CB (91K70)
(1) 50A & (1) 60A Circuit breaker
4208 15.0 51,200 4.3 47 41 50 60
220 16.8 57,300 4.3 52 46 60 60
230 18.4 62,700 4.3 52 46 60 60
240 20.0 68,200 4.3 52 46 60 60
THREE PHASE ELECTRIC HEAT
8 kW
5 lbs.
ECB29-8 (28K42)
Terminal Block
3208 6.0 20,500 4.3 26 − − − 30 − − −
220 6.7 22,900 4.3 29 − − − 30 − − −
230 7.3 25,100 4.3 29 − − − 30 − − −
240 8.0 27,300 4.3 29 − − − 30 − − −
10 kW
6 lbs.
ECB29-10 (28K43)
Terminal Block
3208 7.5 25,600 4.3 31 − − − 35 − − −
220 8.4 28,700 4.3 35 − − − 35 − − −
230 9.2 31,400 4.3 35 − − − 35 − − −
240 10.0 34,100 4.3 35 − − − 35 − − −
15 kW
12 lbs.
ECB29-15CB (28K44)
50A Circuit breaker
3208 11.3 38,400 4.3 44 − − − 445 − − −
220 12.6 43,000 4.3 50 − − − 50 − − −
230 13.5 47,000 4.3 50 − − − 50 − − −
240 15.0 51,200 4.3 50 − − − 50 − − −
20 kW
19 lbs.
ECB29-20CB (28K45)
(2) 35A Circuit breaker
6208 15.0 51,200 4.3 31 21 35 430
220 16.8 57,300 4.3 35 24 35 35
230 18.4 62,700 4.3 35 24 35 35
240 20.0 68,200 4.3 35 24 35 35
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.
2Amps shown are for blower motor only.
3Refer to National or Canadian Electrical Code manual to determine wire, fuse and disconnect size requirements. Use wires suitable for at least 167°F (75_C).
4Bold text indicates that the circuit breaker on CB" circuit breaker models must be replaced with size noted.
5HACR type circuit breaker or fuse.

Page 18
TABLE 6 − ELECTRIC HEAT DATA
SINGLE PHASE ELECTRIC HEAT CBX32MV−048, CBX32MV−060 and CBX32MV−068
Model Number
No.
of
Steps
Volts
Input
kW
Input
1Btuh
Input
2Blower
Motor
Full Load
Amps
3Minimum
Circuit Ampacity
5Maximum
Overcurrent Protection
Circuit
1
Circuit
2
Circuit
3
Circuit
1
Circuit
2
Circuit
3
5 kW
4 lbs.
ECB29-5 (28K31)
Terminal Block
ECB29-5CB (28K32)
30A Circuit breaker
1208 3.8 12,800 9.1 34 − − − − − − 40 − − − − − −
220 4.2 14,300 9.1 37 − − − − − − 45 − − − − − −
230 4.6 15,700 9.1 37 − − − − − − 45 − − − − − −
240 5.0 17,100 9.1 37 − − − − − − 45 − − − − − −
6 kW
4 lbs.
ECB29-6 (47L22)
Terminal Block
ECB29-6CB (47L23)
35A Circuit breaker
1208 4.5 15,400 9.1 36 − − − − − − 45 − − − − − −
220 5.0 17,100 9.1 43 − − − − − − 50 − − − − − −
230 5.5 18,800 9.1 43 − − − − − − 50 − − − − − −
240 6.0 20,500 9.1 43 − − − − − − 50 − − − − − −
8 kW
5 lbs.
ECB29-8 (28K33)
Terminal Block
ECB29-8CB (28K34)
45A Circuit breaker
2208 6.0 20,500 9.1 47 − − − − − − 50 − − − − − −
220 6.7 22,900 9.1 53 − − − − − − 60 − − − − − −
230 7.3 25,100 9.1 53 − − − − − − 60 − − − − − −
240 8.0 27,300 9.1 53 − − − − − − 60 − − − − − −
9 kW
5 lbs.
ECB29-9CB (10L11)
50A Circuit breaker
ECB29EH-9CB (91K67)
50A Circuit breaker
2208 6.8 23,100 9.1 52 − − − − − − 60 − − − − − −
220 7.6 25,800 9.1 58 − − − − − − 60 − − − − − −
230 8.3 28,200 9.1 58 − − − − − − 60 − − − − − −
240 9.0 30,700 9.1 58 − − − − − − 60 − − − − − −
12.5 kW
10 lbs.
ECB29-12.5CB (28K37)
(1) 25A & (1) 50A Circuit breaker
ECB29EH-12.5CB (91K68)
(1) 25A & (1) 50A Circuit breaker
3208 9.4 32,000 9.1 30 31 − − − 440 445 − − −
220 10.5 35,800 9.1 33 35 − − − 445 50 − − −
230 11.5 39,200 9.1 33 35 − − − 445 50 − − −
240 12.5 42,600 9.1 33 35 − − − 445 50 − − −
15 kW
12 lbs.
ECB29-15CB (28K38)
(1) 30A & (1) 60A Circuit breaker
ECB29EH-15CB (91K69)
(1) 30A & (1) 60A Circuit breaker
3208 11.3 38,400 9.1 34 37 − − − 440 450 − − −
220 12.6 43,000 9.1 37 42 − − − 445 60 − − −
230 13.5 47,000 9.1 37 42 − − − 445 60 − − −
240 15.0 51,200 9.1 37 42 − − − 445 60 − − −
20 kW
19 lbs.
ECB29-20CB (11L31)
(1) 50A & (1) 60A Circuit breaker
ECB29EH-20CB (91K70)
(1) 50A & (1) 60A Circuit breaker
4208 15.0 51,200 9.1 53 41 − − − 60 60 − − −
220 16.8 57,300 9.1 58 46 − − − 60 60 − − −
230 18.4 62,700 9.1 58 46 − − − 60 60 − − −
240 20.0 68,200 9.1 58 46 − − − 60 60 − − −
25 kW
19 lbs.
ECB29-25CB (28K40)
(3) 50A Breakers
6208 18.8 64,100 9.1 49 31 31 50 445 445
220 21.0 71,700 9.1 54 35 35 60 50 50
230 23.0 78,300 9.1 54 35 35 60 50 50
240 25.0 85,300 9.1 54 35 35 60 50 50
THREE PHASE ELECTRIC HEAT
8 kW
5 lbs.
ECB29-8 (28K42)
Terminal block
3208 6.0 20,500 9.1 32 − − − − − − 40 − − − − − −
220 6.7 22,900 9.1 35 − − − − − − 40 − − − − − −
230 7.3 25,100 9.1 35 − − − − − − 40 − − − − − −
240 8.0 27,300 9.1 35 − − − − − − 40 − − − − − −
10 kW
6 lbs.
ECB29-10 (28K43)
Terminal block
3208 7.5 25,600 9.1 37 − − − − − − 45 − − − − − −
220 8.4 28,700 9.1 41 − − − − − − 50 − − − − − −
230 9.2 31,400 9.1 41 − − − − − − 50 − − − − − −
240 10.0 34,100 9.1 41 − − − − − − 50 − − − − − −
15 kW
12 lbs.
ECB29-15CB (28K44)
50A Circuit breaker
3208 11.3 38,400 9.1 50 − − − − − − 60 − − − − − −
220 12.6 43,000 9.1 56 − − − − − − 60 − − − − − −
230 13.5 47,000 9.1 56 − − − − − − 60 − − − − − −
240 15.0 51,200 9.1 56 − − − − − − 60 − − − − − −
20 kW
19 lbs.
ECB29-20CB (28K45)
(2) 35A Circuit breakers
6208 15.0 51,200 9.1 37 21 − − − 445 430 − − −
220 16.8 57,300 9.1 41 24 − − − 450 35 − − −
230 18.4 62,700 9.1 41 24 − − − 450 35 − − −
240 20.0 68,200 9.1 41 24 − − − 450 35 − − −
25 kW
19 lbs.
ECB29-25CB (28K46)
(2) 45A Circuit breakers
6208 18.8 64,100 9.1 44 27 − − − 50 440 − − −
220 21.0 71,700 9.1 49 30 − − − 460 45 − − −
230 23.0 78,300 9.1 49 30 − − − 460 45 − − −
240 25.0 85,300 9.1 49 30 − − − 460 45 − − −
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.
2Amps shown are for blower motor only.
3Refer to National or Canadian Electrical Code manual to determine wire, fuse and disconnect size requirements. Use wires suitable for at least 167°F (75_C).
4Bold text indicates that the circuit breaker on CB" circuit breaker models must be replaced with size noted.
5HACR type circuit breaker or fuse.

Page 19
FIGURE 7
ECB29-5, -5CB 208/230 SINGLE−PHASE
ELECTRIC HEAT VESTIBULE PARTS ARRANGEMENT
TERMINAL BLOCK
(TB2)
CIRCUIT BREAKER
(CB1)
PRIMARY LIMIT (S15)
& SECONDARY LIMIT (S20)
ELECTRIC HEAT
ELEMENT (HE1)
ELECTRIC HEAT
VESTIBULE PANEL
ELECTRIC HEAT
SEQUENCER RELAY (K32)
FIGURE 8
ECB29-8 AND -8CB 208/230 SINGLE−PHASE
ELECTRIC HEAT VESTIBULE PARTS ARRANGEMENT
TERMINAL BLOCK
(TB2)
PRIMARY LIMIT (S15)
& SECONDARY LIMIT (S20)
ELECTRIC HEAT
ELEMENT (HE2)
ELECTRIC HEAT
VESTIBULE PANEL
ELECTRIC HEAT
SEQUENCER RELAY (K32)
ELECTRIC HEAT
ELEMENT (HE1)
ELECTRIC HEAT
SEQUENCER RELAY (K33)
ECB29−8 CIRCUIT
BREAKER (CB1)

Page 20
FIGURE 9
ECB29-8,−10 208/230 THREE−PHASE
ECB29-12.5CB, -15CB 208/230 SINGLE & THREE−PHASE
ELECTRIC HEAT VESTIBULE PARTS ARRANGEMENT
TERMINAL BLOCK
(TB2)
CIRCUIT BREAKER
(CB1)
PRIMARY LIMIT (S15)
& SECONDARY LIMIT (S20)
ELECTRIC HEAT
ELEMENT (HE3)
ELECTRIC HEAT
VESTIBULE PANEL
ELECTRIC HEAT
SEQUENCER RELAY (K32)
ELECTRIC HEAT
ELEMENT (HE2)
ELECTRIC HEAT
SEQUENCER RELAY (K33)
CIRCUIT BREAKER
(CB2)
PRIMARY LIMIT (S15)
& SECONDARY LIMIT (S20)
ELECTRIC HEAT
ELEMENT (HE1)
FIGURE 10
ECB29−20CB,−25CB 208/230 THREE−PHASE
ECB29-25CB, -208/230 SINGLE−PHASE
ELECTRIC HEAT VESTIBULE PARTS ARRANGEMENT
CIRCUIT BREAKER
(CB1)
PRIMARY LIMIT (S15)
& SECONDARY LIMIT (S20)
ELECTRIC HEAT
ELEMENT (HE4)
ELECTRIC HEAT
VESTIBULE PANEL
ELECTRIC HEAT
SEQUENCER RELAY (K32)
ELECTRIC HEAT
ELEMENT (HE5)
ELECTRIC HEAT
SEQUENCER RELAY (K33)
CIRCUIT BREAKER
(CB3)
PRIMARY LIMIT (S15)
& SECONDARY LIMIT (S20)
ELECTRIC HEAT
ELEMENT (HE1 & HE2)
(not shown)
ELECTRIC HEAT
ELEMENT (HE6)
ELECTRIC HEAT
SEQUENCER RELAY (K34)
CIRCUIT BREAKER
(CB2)
ELECTRIC HEAT
SEQUENCER RELAY (K35)
ELECTRIC HEAT
SEQUENCER RELAY (K116)
ELECTRIC HEAT
ELEMENT (HE3)