Lennox EL296DFV SERIES Installation and operation manual

Page 1
UNIT INFORMATIONUNIT INFORMATION
Service Literature
©2016 Lennox Industries, Inc.
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.
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.
EL296DFV(X) series units are 90% e󰀩ciency gas furnac-
es used for upow or horizontal applications only, man-
ufactured with Lennox Duralok heat exchangers formed
of aluminized steel. EL296DFV(X) units are available in
heating capacities of 44,000 to 110,000 Btuh and cooling
applications up to 5 tons. Refer to Engineering Handbook
for proper sizing.
Units are factory equipped for use with natural gas. Kits
are available for conversion to LPG operation. EL296D-
FV(X) model units are equipped with a communicating
enabled SureLight® two-stage variable speed integrated
control.
EL296DFV(X) unit meets the California Nitrogen Oxides
(NOx) Standards and California Seasonal E󰀩ciency re-
quirements. All units use a redundant gas valve to assure
safety shut-o󰀨 as required by C.S.A.
All specications in this manual are subject to change.
Procedures outlined in this manual are presented as a
recommendation only and do not supersede or replace lo-
cal or state codes. In the absence of local or state codes,
the guidelines and procedures outlined in this manual (ex-
cept where noted) are recommendations only and do not
constitute code.
TABLE OF CONTENTS
Specications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 2
I Unit Components . . . . . . . . . . . . . . . . . . . . . . . . Page 9
II Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 39
III Start Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 63
IV Heating System Service Checks . . . . . . . . . Page 64
V Typical Operating Characteristics . . . . . . . . . Page 67
VI Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . Page 67
VII Wiring and Sequence of Operation . . . . . . Page 70
VIII Field Wiring and Jumper Settings . . . . . . . Page 73
IX Program Unit Capacity Size Mode . . . . . . . Page 87
X Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . Page 88
EL296DFV(X)
Corp 1126-L5
Revised 03/2022
COMMUNICATING - ENABLED EL296DFV SERIES UNITS

Page 2
SPECIFICATIONS
Gas
Heating
Performance
Model No. EL296DF045XV36BEL296DF070XV48BEL296DF090XV60CEL296DF110XV60C
1 AFUE 96% 96% 96% 96%
High
Fire
Input - Btuh 44,000 66,000 88,000 110,000
Output - Btuh 43,000 64,000 85,000 106,000
Temperature rise range - °F 35-65 35-65 40-70 45-75
Gas Manifold Pressure (in. w.g.)
Nat. Gas / LPG/Propane
3.5 / 10.0 3.5 / 10.0 3.5 / 10.0 3.5 / 10.0
Low
Fire
Input - Btuh 29,000 43,000 57,000 72,000
Output - Btuh 28,000 42,000 56,000 70,000
Temperature rise range - °F 20 - 50 25 - 55 30 - 60 35 - 65
Gas Manifold Pressure (in. w.g.)
Nat. Gas / LPG/Propane
1.7 / 4.5 1.7 / 4.5 1.7 / 4.5 1.7 / 4.5
High static -
in. w.g.
Heating 0.8 0.8 0.8 0.8
Cooling 1.0 1.0 1.0 1.0
Connections
in.
Intake / Exhaust Pipe (PVC) 2 / 2 2 / 2 2 / 2 2 / 2
Gas pipe size IPS 1/2 1/2 1/2 1/2
Condensate Drain Trap (PVC pipe) - i.d. 3/4 3/4 3/4 3/4
with furnished 90° street elbow 3/4 slip x 3/4 Mipt 3/4 slip x 3/4 Mipt 3/4 slip x 3/4 Mipt 3/4 slip x 3/4 Mipt
with eld supplied (PVC coupling) - o.d. 3/4 slip x 3/4 MPT 3/4 slip x 3/4 MPT 3/4 slip x 3/4 MPT 3/4 slip x 3/4 MPT
Indoor
Blower
Wheel nom. diameter x width - in. 10 x 9 11 x 10 11 x 11 11 x 11
Motor output - hp 1/2 3/4 1 1
Tons of add-on cooling 2 - 3 2.5 - 4 3 - 5 3 - 5
Air Volume Range - cfm 545 - 1360 575 - 1800 890 - 2130 860 - 2180
Electrical
Data
Voltage 120 volts - 60 hertz - 1 phase
Blower motor full load amps 7.7 10.1 12.8 12.8
Maximum overcurrent protection 15 20 20 20
Shipping Data lbs. - 1 package 131 136 164 176
NOTE - Filters and provisions for mounting are not furnished and must be eld provided.
1 Annual Fuel Utilization E󰀩ciency based on DOE test procedures and according to FTC labeling regulations. Isolated combustion system rating for non-weatherized
furnaces.

Page 3
OPTIONAL ACCESSORIES - ORDER SEPARATELY
NOTE - FURNACES CANNOT BE TWINNED!
“B” Width Models “C” Width Models
CABINET ACCESSORIES
Downow Combustible Flooring Base 11M60 11M61
High Performance Economizer (Commercial Only) 10U53 10U53
CONDENSATE DRAIN KITS
Condensate Drain Heat Cable 6 ft. 26K68 26K68
24 ft. 26K69 26K69
Crawl Space Vent Drain Kit US 51W18 51W18
Canada 15Z70 15Z70
CONTROLS
iComfort®S30 Ultra-Smart Wi-Fi Thermostat 19V30 19V30
1Discharge Air Temperature Sensor 88K38 88K38
iComfort®E30 Smart Wi-Fi Thermostat 20A65 20A65
2Remote Outdoor Temperature Sensor X2658 X2658
Night Service Kit 15X35 15X35
FILTERS
3 Downow Filter Cabinet 51W07 51W08
No. and Size of lter - in. (2) 16 x 20 x 1 (2) 16 x 20 x 1
TERMINATION KITS
See Installation Instructions for specic venting information.
Direct Vent Concentric US - 2 in. 71M80 69M29
3 in. - - - 60L46
Canada - 2 in. 44W92 44W92
3 in. - - - 44W93
Flush-Mount US - 2, 2-1/2, or 3 in. 51W11 51W11
Canada - 2, 2-1/2, or 3 in. 51W12 51W12
Wall - Close Couple US - 2 in. 22G44 - - -
3 in. 44J40 44J40
Wall - Close Couple WTK Canada - 2 in. 30G28 - - -
3 in. 81J20 81J20
Roof Termination Flashing Kit
(no vent pipe - 2 ashings)
2 in. 15F75 15F75
3 in. 44J41 44J41
VENTING
Flue Coupling 2 in. 17H92 17H92
⁴ Left Side Vent Kit 2 or 3 in. 87W73 87W73
1 Optional for service diagnostics.
2 Remote Outdoor Temperature Sensor is used with conventional (non-iComfort® Communicating) outdoor units (sensor is furnished with iComfort® Communicating
outdoor units). Allows the thermostat to display outdoor temperature. Required in dual-fuel and EDA applications.
3 Cleanable polyurethane, frame-type lter.
4 NOTE - The curved exhaust pipe furnished with the Left Side Vent Kit counts as one additional 2 in. diameter 90° elbow. When using 3 in. diameter pipe, the furnished
curved exhaust pipe and eld provided ttings to transition from 2 in. to 3 in. count as 20 feet of equivalent pipe on all units.
NOTE - Termination Kits (44W92, 44W93, 30G28, 51W12, 81J20) and Crawl Space Vent Drain Kit (15Z70) are certied to ULC S636 standard for use in Canada only.

Page 4
BLOWER DATA
EL296DF045XV36B BLOWER PERFORMANCE (less lter)
BOTTOM RETURN AIR
0 through 0.8 in. w.g. (Heating) and 0 through 1.0 in. w.g. (Cooling) External Static Pressure Range
HEATING
1Heating Speed
DIP Switch
Settings
First Stage Heating Speed - cfm Second Stage Heating Speed - cfm
+24% 910 1150
+18% 855 1095
+12% 820 1040
+6% 770 990
Factory Default 745 935
–6% 700 880
–12% 665 820
–18% 635 755
COOLING
1Cooling Speed
DIP Switch
Settings
First Stage Cooling Speed - cfm Second Stage Cooling Speed - cfm
Low Medium-Low Medium-High 2High Low Medium-Low Medium-High 2High
[phone] 1050 1210 1360
Factory Default 580 695 780 880 805 965 1105 1250
–545 645 720 795 735 865 1000 1130
1 Cooling and heating speeds are based on a combination of DIP switch settings on the furnace control. Refer to Installation Instructions for specic DIP Switch Settings.
2 Factory default setting.
NOTES - The e󰀨ect of static pressure is included in air volumes shown.
First stage HEAT is approximately 91% of the same second stage HEAT.
First stage COOL (two-stage air conditioning units only) is approximately 70% of the same second stage COOL speed position.
Continuous Fan Only speed is selectable at 28% and 38% of the selected second stage cooling speed - minimum 250 cfm.
Lennox iHarmony® Zoning System Applications - Minimum blower speed is 250 cfm.
EL296DF045XV36B BLOWER MOTOR WATTS (COOLING)
1Cooling Speed
DIP Switch
Settings
Motor Watts @ Various External Static Pressures - in. wg.
First Stage Second Stage
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
+ Setting
Cooling
Speed
Low 28 44 60 77 93 112 128 144 158 59 77 97 121 138 160 182 197 216 241 256
Med-low 47 67 88 105 121 138 161 179 201 131 154 177 202 228 250 277 299 320 344 370
Med-High 69 91 113 132 160 183 204 220 246 199 215 248 275 308 340 360 390 407 431 445
High 100 117 153 172 192 215 240 260 286 292 313 363 379 419 452 488 511 526 523 524
Factory Default
Cooling
Speed
Low 17 34 52 65 82 97 121 132 148 61 79 98 125 141 164 185 201 219 246 259
Med-low 35 50 70 85 105 125 140 155 175 99 115 148 167 188 211 236 256 279 303 317
Med-High 54 72 95 113 131 148 173 189 210 147 170 197 223 252 278 301 330 355 373 398
High 74 96 118 141 168 190 212 233 252 216 229 258 303 325 356 390 410 426 448 465
– Setting
Cooling
Speed
Low 17 31 49 61 75 91 107 123 136 46 64 82 101 115 134 155 174 196 205 221
Med-low 28 45 61 77 93 112 129 144 159 72 92 114 133 160 184 204 221 247 263 282
Med-High 40 57 77 93 112 130 148 165 186 112 130 161 183 205 226 252 272 294 319 341
High 57 76 97 119 136 156 179 195 214 155 174 207 235 265 292 311 343 370 386 414

Page 5
BLOWER DATA
EL296DF070XV48B BLOWER PERFORMANCE (less lter)
BOTTOM RETURN AIR
0 through 0.8 in. w.g. (Heating) and 0 through 1.0 in. w.g. (Cooling) External Static Pressure Range
HEATING
1Heating Speed
DIP Switch
Settings
First Stage Heating Speed - cfm Second Stage Heating Speed - cfm
+24% 1085 1635
+18% 1030 1525
+12% 950 1450
+6% 910 1365
Factory Default 850 1310
–6% 790 1225
–12% 740 1135
–18% 680 1060
COOLING
1Cooling Speed
DIP Switch
Settings
First Stage Cooling Speed - cfm Second Stage Cooling Speed - cfm
Low Medium-Low Medium-High 2High Low Medium-Low Medium-High 2High
[phone] 1110 1340 1575 1800
Factory Default 660 820 940 1120 995 1230 1420 1650
–575 735 850 995 880 1085 1290 1460
1 Cooling and heating speeds are based on a combination of DIP switch settings on the furnace control. Refer to Installation Instructions for specic DIP Switch Settings.
2 Factory default setting.
NOTES - The e󰀨ect of static pressure is included in air volumes shown.
First stage HEAT is approximately 91% of the same second stage HEAT.
First stage COOL (two-stage air conditioning units only) is approximately 70% of the same second stage COOL speed position.
Continuous Fan Only speed is selectable at 28% and 38% of the selected second stage cooling speed - minimum 380 cfm.
Lennox iHarmony® Zoning System Applications - Minimum blower speed is 380 cfm.
EL296DF070XV48B BLOWER MOTOR WATTS (COOLING)
1Cooling Speed
DIP Switch
Settings
Motor Watts @ Various External Static Pressures - in. wg.
First Stage Second Stage
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
+ Setting
Cooling
Speed
Low 68 88 109 132 154 178 199 213 238 144 169 208 244 270 310 343 378 401 432 457
Med-low 93 120 147 172 198 220 254 274 304 257 276 326 370 398 437 470 492 531 558 598
Med-High 120 152 180 220 254 281 318 344 380 390 428 472 526 574 611 659 706 745 788 820
High 214 237 284 324 352 390 424 456 474 627 604 663 721 775 825 869 908 915 881 864
Factory Default
Cooling
Speed
Low 35 54 74 92 109 129 147 163 191 104 137 162 189 219 254 278 312 341 369 400
Med-low 75 100 115 140 165 190 210 230 255 188 203 250 297 327 374 399 432 454 486 513
Med-High 99 129 159 179 209 236 270 293 329 304 340 376 418 450 495 533 567 613 637 674
High 157 184 232 264 285 335 365 406 419 454 469 537 589 634 669 724 770 818 833 840
– Setting
Cooling
Speed
Low 27 49 63 73 98 116 135 155 168 86 111 135 162 186 206 236 257 283 306 339
Med-low 67 87 109 132 154 177 199 212 238 129 156 187 226 258 288 325 353 385 409 441
Med-High 82 105 127 153 176 196 223 243 269 226 244 290 335 364 402 435 465 485 516 556
High 107 141 164 195 224 263 282 321 347 329 375 403 444 481 526 570 612 656 680 718

Page 6
BLOWER DATA
EL296DF090XV60C BLOWER PERFORMANCE (less lter)
BOTTOM RETURN AIR
0 through 0.8 in. w.g. (Heating) and 0 through 1.0 in. w.g. (Cooling) External Static Pressure Range
HEATING
1Heating Speed
DIP Switch
Settings
First Stage Heating Speed - cfm Second Stage Heating Speed - cfm
+24% 1425 1895
+18% 1355 1825
+12% 1280 1740
+6% 1215 1660
Factory Default 1160 1575
–6% 1055 1455
–12% 1010 1365
–18% 950 1265
COOLING
1Cooling Speed
DIP Switch
Settings
First Stage Cooling Speed - cfm Second Stage Cooling Speed - cfm
Low Medium-Low Medium-High 2High Low Medium-Low Medium-High 2High
[phone] 1600 1600 1750 1970 2130
Factory Default 1005 1150 1275 1450 1450 1630 1810 1975
–890 1065 1150 1270 1270 1450 1645 1810
1 Cooling and heating speeds are based on a combination of DIP switch settings on the furnace control. Refer to Installation Instructions for specic DIP Switch Settings.
2 Factory default setting.
NOTES - The e󰀨ect of static pressure is included in air volumes shown.
First stage HEAT is approximately 91% of the same second stage HEAT.
First stage COOL (two-stage air conditioning units only) is approximately 70% of the same second stage COOL speed position.
Continuous Fan Only speed is selectable at 28% and 38% of the selected second stage cooling speed - minimum 450 cfm.
Lennox iHarmony® Zoning System Applications - Minimum blower speed is 450 cfm.
EL296DF090XV60C BLOWER MOTOR WATTS (COOLING)
1Cooling Speed
DIP Switch
Settings
Motor Watts @ Various External Static Pressures - in. wg.
First Stage Second Stage
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
+ Setting
Cooling
Speed
Low 79 108 144 162 207 242 262 293 323 275 299 366 399 449 483 532 584 605 644 680
Med-low 120 156 187 233 261 279 329 368 401 387 409 471 521 562 606 650 688 716 762 800
Med-High 155 202 235 293 317 369 407 453 502 547 577 622 667 744 795 835 872 910 950 963
High 268 299 366 399 449 483 532 584 605 780 775 811 898 942 994 1048 1071 1082 1080 1073
Factory Default
Cooling
Speed
Low 56 86 111 140 170 200 232 259 282 186 219 270 308 361 390 431 489 517 555 590
Med-low 93 118 152 195 223 254 283 306 344 278 304 365 420 450 510 544 592 640 665 698
Med-High 123 161 201 228 260 310 341 381 416 446 475 528 582 616 662 686 747 780 823 855
High 182 219 270 308 361 390 431 489 517 576 603 654 704 756 809 871 902 939 972 975
– Setting
Cooling
Speed
Low 48 69 101 120 152 175 201 218 249 118 155 181 232 259 299 340 376 402 438 476
Med-low 65 94 123 150 185 220 250 278 296 177 205 267 304 353 390 430 486 515 563 587
Med-High 93 118 152 195 223 254 283 306 344 301 322 392 439 468 531 568 599 647 678 721
High 116 155 181 232 259 299 340 376 402 446 475 528 582 616 662 686 747 780 823 855

Page 7
BLOWER DATA
EL296DF110XV60C BLOWER PERFORMANCE (less lter)
BOTTOM RETURN AIR
0 through 0.8 in. w.g. (Heating) and 0 through 1.0 in. w.g. (Cooling) External Static Pressure Range
HEATING
1Heating Speed
DIP Switch
Settings
First Stage Heating Speed - cfm Second Stage Heating Speed - cfm
+24% 1535 2015
+18% 1445 1935
+12% 1370 1855
+6% 1300 1760
Factory Default 1220 1645
–6% 1135 1545
–12% 1070 1420
–18% 1000 1335
COOLING
1Cooling Speed
DIP Switch
Settings
First Stage Cooling Speed - cfm Second Stage Cooling Speed - cfm
Low Medium-Low Medium-High 2High Low Medium-Low Medium-High 2High
[phone] 1585 1585 1790 1990 2180
Factory Default 965 1130 1285 1440 1440 1630 1845 2005
–860 1035 1130 1275 1275 1475 1655 1845
1 Cooling and heating speeds are based on a combination of DIP switch settings on the furnace control. Refer to Installation Instructions for specic DIP Switch Settings.
2 Factory default setting.
NOTES - The e󰀨ect of static pressure is included in air volumes shown.
First stage HEAT is approximately 91% of the same second stage HEAT.
First stage COOL (two-stage air conditioning units only) is approximately 70% of the same second stage COOL speed position.
Continuous Fan Only speed is selectable at 28% and 38% of the selected second stage cooling speed - minimum 450 cfm.
Lennox iHarmony® Zoning System Applications - Minimum blower speed is 450 cfm.
EL296DF110XV60C BLOWER MOTOR WATTS (COOLING)
1Cooling Speed
DIP Switch
Settings
Motor Watts @ Various External Static Pressures - in. wg.
First Stage Second Stage
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
+ Setting
Cooling
Speed
Low 71 99 147 166 202 240 271 302 337 248 280 333 374 429 469 511 548 594 619 677
Med-low 127 159 198 225 256 301 325 365 390 409 427 496 531 587 632 665 721 742 781 805
Med-High 162 204 242 287 316 371 408 446 487 563 589 651 703 755 808 860 888 932 970 1007
High 243 280 333 374 429 469 511 548 594 866 850 915 963 1020 1056 1091 1127 1141 1136 1131
Factory Default
Cooling
Speed
Low 57 88 117 140 165 196 232 259 283 167 214 244 291 331 380 405 467 497 539 583
Med-low 77 112 147 172 209 250 283 317 345 275 321 348 418 447 505 546 597 632 668 716
Med-High 122 154 199 230 268 300 331 373 411 461 493 547 572 628 666 703 745 777 819 860
High 167 214 244 291 331 380 405 467 497 601 626 688 730 787 823 880 924 963 994 1011
– Setting
Cooling
Speed
Low 44 67 99 115 144 167 197 215 245 126 165 201 232 262 305 334 373 417 451 479
Med-low 66 97 123 153 186 216 247 275 303 187 219 272 308 360 391 432 479 514 559 588
Med-High 77 112 147 172 209 250 283 317 345 308 341 390 430 490 528 569 617 640 691 724
High 127 165 201 232 262 305 334 373 417 461 493 547 572 628 666 703 745 777 819 860

Page 8
PARTS IDENTIFICATION
CONTROL BOX
(Includes integrated control,
transformer and door switch)
BAG ASSEMBLY
(shipping location)
VARIABLE SPEED MOTOR
(hidden)
OUTER
ACCESS
PANEL
COMBUSTION
AIR INDUCER
BURNER BOX ASSEMBLY
(includes sensor, rollout switches and ignitor) GAS VALVE
BLOWER DECK
COLD END HEADER BOX
PRIMARY LIMIT
DuralokPlusTM
HEAT EXCHANGER
ASSEMBLY
COMBUSTION AIR INDUCER
PRESSURE SWITCH
FIGURE 1

Page 9
I-UNIT COMPONENTS
EL296DFV(X) unit components are shown in FIGURE 1.
The gas valve, combustion air inducer and burners can be
accessed by removing the access panel. Electrical com-
ponents are in the control box (FIGURE 2) found in the
blower section.
ELECTROSTATIC DISCHARGE (ESD)
Precautions and Procedures
CAUTION
Electrostatic discharge can a󰀨ect
electronic components. Take precautions
to neutralize electrostatic charge by
touching your hand and tools to metal
prior to handling the control.
A- Control Box
1. Control Transformer (T1)
A transformer located in the control box provides power
to the low voltage section of the unit. Transformers on all
models are rated 40VA with a 120V primary and a 24V
secondary.
2. Door Interlock Switch (S51)
A door interlock switch rated 14A at 125VAC is wired in se-
ries with line voltage. When the inner blower access panel
is removed the unit will shut down.
CONTROL BOX
Transformer
SureLight®Integrated Control
Interlock Switch
Circuit Breaker
FIGURE 2
3. Circuit Breaker (CB8)
A 24V circuit breaker is also located in the control box.
The switch provides overcurrent protection to the trans-
former (T1). The breaker is rated 3A at 32V. If the current
exceeds this limit the breaker will trip and all unit opera-
tion will shutdown. The breaker can be manually reset by
pressing the button on the face. See FIGURE 3.
CIRCUIT BREAKER CB8
PRESS TO RESET
FIGURE 3
WARNING
Shock hazard.
Disconnect power before servicing. Integrated
control is not eld repairable. If control is inoperable,
simply replace entire control.
Can cause injury or death. Unsafe operation will
result if repair is attempted.
4. Integrated Control (A92)
Units are equipped with a communicating enabled Sure-
Light ® two-stage, variable speed integrated control. This
control is used with a communicating thermostat as part
of a communicating comfort system. The control can also
operate with a non-communicating conventional single or
two-stage thermostat. The system consists of a ignition
/ blower control (FIGURE 4 103130-05 and FIGURE 5
107045-01) with control pin designations in TABLE 1, TA-
BLE 2, TABLE 3 and ignitor (FIGURE 14). The control and
ignitor work in combination to ensure furnace ignition and
ignitor durability. The control provides gas ignition, safety
checks and indoor blower control with two-stage gas heat-
ing. The furnace combustion air inducer, gas valve and in-
door blower are controlled in response to various system
inputs such as thermostat signal, pressure and limit switch
signal and ame signal. The control features a seven-seg-
ment LED display, indicating furnace status (including in-
door blower) and error codes. The LED ashes in single
digits. For example using TABLE 5 under LIMIT CODE, an
“E” followed by “2” followed by “5” followed by “0”, the limit
switch circuit is open. The control also has two unpowered
(dry) 1/4” contacts for a humidier and a 120 volt accesso-
ry terminal. Both rated at (1) one amp each.
Electronic Ignition
At the beginning of the heat cycle the integrated control
monitors the rst stage and second stage combustion air
inducer prove switch. The control will not begin the heating
cycle if the rst stage prove switch is closed (by-passed).
Likewise the integrated control will not begin the second
stage heating cycle if the second stage prove switch is
closed, and will remain in rst stage heat. However, if the
second stage prove switch closes during the rst stage
heat pre-purge, the control will allow second stage heat.
Once the rst stage prove switch is determined to be open,
the combustion air inducer is energized on low (rst stage)
heat speed. When the di󰀨erential in the prove switch is
great enough, the prove switch closes and a 15-second
pre-purge begins.

Page 10
NOTE - During abnormal conditions such as low supply
voltage or low outdoor temperatures and the low re pres-
sure switch does not close, the combustion air inducer will
switch to high re. After a 15 second pre-purge the high
re pressure switch will close and the unit will begin op-
eration on high re. After 10 to 20 seconds of high re
operation the unit will switch to low re.
After the 15-second pre-purge period, the SureLight ig-
nitor warms up for 20 seconds after which the gas valve
opens for a 4-second trial for ignition. The ignitor remains
energized during the trial until ame is sensed. If ignition
is not proved during the 4-second period, the control will
try four more times with an inter purge and warm-up time
between trials of 35 seconds. After a total of ve trials for
ignition (including the initial trial), the control goes into
Watchguard- Flame Failure mode. After a 60-minute reset
period, thecontrol will begin the ignition sequence again.
Two Stage Operation / Thermostat Selection DIP
Switch
The control can be utilized in two modes: SINGLE-STAGE
thermostat or TWO-STAGE thermostat. The thermostat
selection is made using a DIP switch and must be posi-
tioned for the particular application. DIP switch 1, labeled
T”STAT HEAT STAGE is factory-set in the OFF position
for use with a two-stage thermostat. Move the DIP switch
to ON for use with a single stage thermostat. While in the
single-stage thermostat mode, the burners will always re
on rst-stage heat. The combustion air inducer will oper-
ate on low speed and indoor blower will operate on low
heat speed. The unit will switch to second stage heat af-
ter a “recognition period”. DIP switch 2, labeled SECOND
STAGE DELAY, is factory set in the OFF position for a 7
minute recognition period. The switch can be moved to the
ON position for a 12 minute recognition period, after which
time the unit will switch to secondstage heat. While in the
two-stage thermostat mode, the burners will re on rst-
stage heat. The combustion air inducer will operate on low
speed and indoor blower will operate on low heat speed.
The unit will switch to second-stage heat on call from the
indoor thermostat. If there is a simultaneous call for rst
and second stage heat, the unit will re an rst stage heat
and switch to second stage heat after 30 seconds of oper-
ation. See Sequence of Operation ow charts in the back
of this manual for more detail.
TABLE 1
SureLight® Control 5 Pin Terminal Designation
Pin # Function
1Ignitor
2Combustion Air Inducer High
Speed
3 Combustion Air Inducer Low
Speed
4 Combustion Air Inducer Neutral
5 Ignitor Neutral
TABLE 2
SureLight®Control 12 Pin Terminal Designation
Pin # Function
1Gas Valve Second Stage
2Second Stage Prove Switch
3 Rollout Switch In
4 Ground
5 24V Hot
6Primary Limit In
7 Gas Valve First Stage
8 Gas Valve Common
924V Neutral
10 Ground
11 Rollout Switch Out
12 First Stage Prove Switch
TABLE 3
SureLight® Control 6 Pin Terminal Designation
Pin # Function
1Data Input From Motor
2Common
3 Not Used
4 Data Output To Motor
5 5 Volt Bias Supply
6Not Used

Page 11
INTEGRATED CONTROL 103130-05
THERMOSTAT CONNECTIONS (TB1)
1/4” QUICK CONNECT TERMINALS
TB83 icomfort Communicating Outdoor Equipment
R = 24VAC
I + = DATA HIGH CONNECTION
I - = DATA LOW CONNECTION
C = 24VAXC COMMON
R = 24VAC
I + = DATA HIGH CONNECTION
I - = DATA LOW CONNECTION
C = 24VAXC COMMON
FLAME SENSE
DIP SWITCHES
OUTDOOR AIR
SENSOR
TERMINALS
DISCHARGE AIR
SENSOR
TERMINALS
INDOOR
BLOWER
CONNECTOR
NEUTRAL
DIAGNOSTIC
PUSH BUTTON
TB83
icomfort
COMMUNICATING
OUTDOOR
EQUIPMENT
TB84
icomfort
COMMUNICATING
INDOOR
THERMOSTAT
DS = DEHUMIDIFICATION SIGNAL
W2 = HEAT DEMAND FROM 2ND STAGE T/STAT
W1 = HEAT DEMAND FROM 1ST STAGE T/STAT
R = CLASS 2 VOLTAGE TO THERMOSTAT
G = MANUAL FAN FROM T'STAT
C = THERMOSTAT SIGNAL GROUND CONNECTED TO
TRANSFORMER GRD (TR) & CHASIS GROUND (GRD)
Y1 = THERMOSTAT 1ST STAGE COOL SIGNAL
Y2 = THERMOSTAT 2ND STAGE COOL SIGNAL
O = THERMOSTAT SIGNAL TO HEAT PUMP
REVERSING VALVE
L = USE ONLY WITH A COMMUNICATING THERMOSTAT
AND A NON-COMMUNICATING OUTDOOR UNIT
DH = DEHUMIDIFICATION OUTPUT COMMUNICATING
THERMOSTAT ONLY
HUM = UNPOWERED NORMALLY OPEN (DRY) CONTACTS
XMFR = 120 VAC OUTPUT TO TRANSFORMER
LI = 120 VAC INPUT TO CONTROL
ACC = 120 VAC OUTPUT TO OPTIONAL ACCESSORY
NEUTRALS = 120 VAC NEUTRAL
W915 Y1 TO Y2
2 STAGE COMPR
W951 R TO O
HEAT PUMP
W914 R TO DS
DEHUM OR
HARMONY
W1 W2 G Y2 Y1 CCRDHL ODS
RI +I- CRI +I- C
7 SEGMENT LED
ACC
LINE 1
HUM
12 PIN LOW
VOLTAGE
CONNECTOR
NON-COMMUNICATING
24V TERMINALS
HS/ CAI
TB84 icomfort Communicating Indoor Thermostat
FIGURE 4

Page 12
THERMOSTAT CONNECTIONS (TB1)
1/4” QUICK CONNECT TERMINALS
RS-BUS LINK (TB82, future use)
I+ = DATA HIGH CONNECTION
I - = DATA LOW CONNECTION
R = 24VAC
I + = DATA HIGH CONNECTION
I - = DATA LOW CONNECTION
C = 24VAC COMMON (ground)
RS-BUS INDOOR (TB84)
R = 24VAC
I + = DATA HIGH CONNECTION
I - = DATA LOW CONNECTION
C = 24VAC COMMON
A2L=A2L REFRIGERANT
DS = DEHUMIDIFICATION SIGNAL
W2 = HEAT DEMAND FROM 2ND STAGE T/STAT
W1 = HEAT DEMAND FROM 1ST STAGE T/STAT
R = CLASS 2 VOLTAGE TO THERMOSTAT
G = MANUAL FAN FROM T'STAT
C = THERMOSTAT SIGNAL GROUND CONNECTED TO
TRANSFORMER GRD (TR) & CHASIS GROUND (GRD)
Y1 = THERMOSTAT 1ST STAGE COOL SIGNAL
Y2 = THERMOSTAT 2ND STAGE COOL SIGNAL
O = THERMOSTAT SIGNAL TO HEAT PUMP
REVERSING VALVE
L = NOT USED
DH = DEHUMIDIFICATION OUTPUT COMMUNICATING
THERMOSTAT ONLY
HUM = UNPOWERED NORMALLY OPEN (DRY) CONTACTS
XMFR = 120 VAC OUTPUT TO TRANSFORMER
LI = 120 VAC INPUT TO CONTROL
ACC = 120 VAC OUTPUT TO OPTIONAL ACCESSORY
NEUTRALS = 120 VAC NEUTRAL
H = LOW VOLTAGE (24 VAC) HUMIDIFICATION
IGNITION CONTROL 107045-01
FIGURE 5

Page 13
HEATING BLOWER−OFF DELAY
60 SECOND
HTG BLOWER
OFF DELAY
120 SECOND
HTG BLOWER
OFF DELAY
180 SECOND
HTG BLOWER
OFF DELAY
FLAME
15
HSI/CAI
2ND STAGE HEAT ON DELAY
7 MIN
UPSTAGE
DELAY
12 MIN
UPSTAGE
DELAY
*CONTINUOUS FAN MODE BLOWER SPEED
COOLING MODE BLOWER RAMPING
CLG BLOWER SPEED ADJUSTMENT
COOLING MODE BLOWER SPEED
W915
2 STAGE
COMPR
1−STG COMPRESSOR
2−STAGE
COMPRESSOR LINK
(JUMPERS Y1 to Y2)
W915
DO NOT CUT
2−STG COMPRESSOR
HEAT PUMP LINK
(JUMPERS R to O)
W951
DEHUMIDIFICATION−
HARMONY LINK
(JUMPERS R to DS)
W914
W915
2 STAGE
COMPR
CUT LINK
A/C UNIT
DO NOT CUT
HEAT PUMP UNIT
CUT LINK
W951
HEAT
PUMP
W951
HEAT
PUMP
W914
DEHUM
or
NO HARMONY ZONING
OR
NO SIGNATURESTAT
W/ DS CONNECTION
DO NOT CUT
HARMONY ZONING
OR
SIGNATURESTAT W/
DS CONNECTION
CUT LINK
HARMONY
W914
DEHUM
or
HARMONY
1
1
1
ON−BOARD LINK
OPTION SELECTION
1234567
1234567
123567
4
123567
4
NEUTRALS
L1
ACC
HUM
14
36
P79
110
312
J2
4 7
W915
2 STAGE
COMPR
W951
HEAT
PUMP
W914
DEHUM
HARMONY
CUT FOR
OPTION
SELECTION
OUTDOOR SENSOR
DISCHARGE
AIR SENSOR
123456
10 12
91113
ON
ON
SureLight

W1W2 GY2 Y1 CC DH LODSR
W1 W2
G
Y2
Y1
C C
R
L
DH
HIGH
SPEED
(100%)
MEDIUM−HIGH
SPEED
(70%)
MEDIUM−LOW
SPEED
(38%)
LOW
SPEED
(28%)
*
OPTION A
OFF−50%−82%−
100%−50%−OFF
OPTION B
OFF−82%−100%−OFF
OPTION C
OFF−100%−100%−OFF
OPTION D
OFF−100%−OFF
*
DEFAULT
+ 10%
− 10%
*
HIGH
SPEED
MEDIUM−HIGH
SPEED
MEDIUM−LOW
SPEED
LOW
SPEED
*
7
−PROTECTIVE PLASTIC FILM ON DIP SWITCHES MAY BE
REMOVED FOR EASE IN SETTING OF DIP SW.
−CUT ON−BOARD LINK (SOLDER TRACE) COMPLETELY THROUGH
BOTH LAYERS ON THE CONTROL BOARD
−LINKS CUT IN ERROR −INSTALL A JUMPER ON THE APPROPRIATE
TERMINALS ON THE TERMINAL STRIP
1
910 11
12 13
14
ON
ON
ON
ON
ON
ON
ON
ON
90 SECOND
HTG BLOWER
OFF DELAY
*1234567
ON
1234567
ON
THERMOSTAT SELECTION
1−STAGE
THERMOSTAT
(TIMED STAGING)
−SEE SW #2
TWO STAGE
THERMOSTAT
*1234567
1234567
ON
ON
−BLOWER ON DELAY − 30 SEC. FIXED
15
9
10 11
12 14 15
9
10 11
12 14 15
9
10 11
12 14 15
8
8
8
8
8
8
8
8
1234567
1234567
ON
ON
1234567
ON
1234567
ON
8
8
8
8
9
10 11
12 13
14
ON
ON
ON
ON
15
910 11
12 14 15
910 11
12 14 15
9
10 11
12 14 15
910 11
12 13
14
ON
ON
ON
ON
15
910 11
12 14 15
910 11
12 14 15
910 11
12 14 15
HEATING MODE BLOWER SPEED
1234567
ON
1234567
ON
1234567
ON
8
8
8
910 11
12 13
14
ON
ON
ON
ON
15
9
10 11
12 14 15
910 11
12 14 15
9
10 11
12 14 15
FACTORY
DEFAULT
+ 24%
+ 18%
+ 12%
+ 6%
− 6%
− 12%
− 18%
8
14 15
INCREASE AIR HTG CFM
DECREASE AIR HTG CFM
SENSE
RI+ I− CRI+ I− C
OUTDOOR EQUIPMENT
I+ I−
INDOOR EQUIPMENT
IGN
CAI2
CAI1
N N
J3
S1
S4S3
13
13
13
13
13
13
13
* FACTORY DEFAULT
13
13
*
DIAGNOSTIC
LED
DIAGNOSTIC
PUSH BUTTON
INTEGRATED CONTROL CONFIGURATION GUIDE
FIGURE 6

Page 14
TABLE 4
Ignition Control 103130-05 Diagnostic Modes
Display Action (when button released)
No change (idle)* Remain in idle mode
Solid “E” Enter diagnostic recall mode
Solid “D” Discharge Air Installed
Solid “F” Enter ame signal mode
Solid “P” (variable speed only) Program unit capacity/size (Unit Code)
Two horizontal bars = Soft disable
* No change implies the display will continue to show whatever is currently being displayed for normal operation (blinking decimal, active error code,
heat state, etc..)
Diagnostic LED
The seven-segment diagnostic LED displays operating
status, target airow, error codes and other information.
The table beginning on Page 9 lists diagnostic LED codes.
Diagnostic Push Button
The diagnostic push button is located adjacent to the sev-
en-segment diagnostic LED. This button is used to enable
the Error Code Recall “E” mode and the Flame Signal
“F” mode. Press the button and hold it to cycle through a
menu of options. Every ve seconds a new menu item will
be displayed. When the button is released, the displayed
item will be selected. Once all items in the menu have
been displayed, the menu resumes from the beginning
until the button is released.
Error Code Recall Mode
Select ”E” from the menu to access the most recent 10
error codes. Select “c” from the Error Code Recall menu
to clear all error codes. Button must be pressed a second
time while “c” is ashing to conrm command to delete
codes. Press the button until a solid “≡” is displayed to exit
the Error Code Recall mode.
Flame Signal Mode
Select ”F” from the menu to access the ame signal mode.
The integrated control will display the ame current on 7
segment LED in micro amps (uA).
• Flame signal mode is exited after any of the follow-
ing: Power is reset
• Pressing and holding push button until 3 horizontal
lines “≡” are displayed
• 10 minutes after entering the ame sense mode
Program Unit Capacity/Size Mode
After the “P” is selected (by releasing the push button)
the integrated control will start ashing the “P” on display
for 90 seconds. If push button is pressed again and held
during that time, the control will start to display characters
corresponding to di󰀨erent variable speed furnace models
for 3 seconds each. While the wanted character-model is
displayed push button has to be released. Selected option
will ash display for 10 seconds and during that time push
button has to be pressed and held for 5 seconds. Once
control accepts new setting it will store data in non-volatile
memory and reset itself. If 10 seconds expires or push
button is held less than 5 seconds, control will exit eld
test mode and go into idle without changing programming
the unit size.
Soft Disable
Soft disabling is when thermostat nds a device on the
BUS that it does not recognize and the thermostat sends
a the device a message to be in soft disabling mode until
properly congured. Two horizontal bars will display.
Steps to follow if the damper control module is displaying
the soft disable code.
1 - Conrm proper wiring between all devices
(thermostat, damper control module, indoor and
outdoor).
2 - Cycle power to the control that is displaying the soft
disable code.
3 - Put the room thermostat through set up.
4 - Go to setup / system devices / thermostat / edit
/ then push reset.
5 - Go to setup / system devices / thermostat / edit /
then push resetAll.

Page 15
TABLE 5
Ignition Control 103130-05 Diagnostic Codes
Code Diagnostic Codes/Status of Equipment Action Required to Clear and Recover
. Idle mode (Decimal blinks at 1 Hertz -- 0.5
second ON, 0.5 second OFF).
A Cubic feet per minute (cfm) setting for
indoor blower (1 second ON, 0.5 second
OFF) / cfm setting for current mode
displayed.
C Cooling stage (1 second ON, 0.5 second
OFF) / 1 or 2 displayed / Pause / cfm
setting displayed / Pause / Repeat codes).
dDehumidication mode (1 second ON) /
1 second OFF) / cfm setting displayed /
Pause / Repeat Codes).
h Heat pump stage (1 second ON, 0.5
second OFF) / % of input rate displayed
/ Pause / cfm setting / Pause / Repeat
codes.
H Gas Heat Stage (1 second ON, 0.5 second
OFF) / 1 or 2 displayed / Pause / cfm
setting displayed / Pause / Repeat codes.
Blinking during ignition.
dF Defrost mode.
UDischarge Air Temperature
E105 Device communication problem - No other
devices on RS BUS (Communication
system).
Equipment is unable to communicate. Indicates numerous message
errors. In most cases errors are related to electrical noise. Make sure
high voltage power is separated from RSBus. Check for miswired and/or
loose connections between the stat, indoor unit and outdoor unit. Check
for a high voltage source of noise close to the system. Fault clears after
communication is restored.
E110 Low line voltage. Line Voltage Low (Voltage lower than nameplate rating). Check power line
voltage and correct. Alarm clears 5 seconds after fault recovered.
E111 Low line voltage. Reverse line power voltage wiring. System resumes normal operation 5
seconds after fault recovered.
E112 Ground not detected System shuts down. Provide proper earth ground. System resumes normal
operation 5 seconds after fault recovered.
E113 High line voltage. Line Voltage High (Voltage higher than nameplate rating). Provide power
voltage within proper range. System resumes normal operation 5 seconds
after fault recovered.
E114 Line voltage frequency out-of-range. No 60 Hertz Power. Check voltage and line power frequency. Correct
voltage and frequency problems. System resumes normal operation 5
seconds after fault recovered.
E115 Low 24V - Control will restart if the error
recovers.
24-Volt Power Low (Range is 18 to 30 volts). Check and correct voltage.
Check for additional power-robbing equipment connected to system. May
require installation of larger VA transformer to be installed in furnace / air
handler. Clears after fault recovered.
E116 High 24V. 24 Volt Power High (Range is 18 to 30 volts). Check and correct voltage.
Check for proper line voltage (120V, 240V, etc.) to equipment. Clears when
control senses proper voltage.
E117 Poor ground detected (Warning only) Provide proper grounding for unit. Check for proper earth ground to the
system. Warning only will clear 30 seconds after fault recovered.
E120 Unresponsive device. Communication
only.
Usually caused by delay in outdoor unit responding to indoor unit poling.
Recycle power. Check all wiring connections. Cleared after unresponsive
device responds to any inquiry.

Page 16
TABLE 5 Continued
Ignition Control 103130-05 Diagnostic Codes
Code Diagnostic Codes/Status of Equipment Action Required to Clear and Recover
E124 Active communicating thermostat signal
missing for more than 3 minutes.
Equipment lost communication with the thermostat. Check
four wiring connections, ohm wires and cycle power at the
thermostat. Alert stops all services and waits for heartbeat
message from thermostat (subnet controller). Cleared after
valid thermostat (subnet controller) message is received.
E125 Control failed self-check, internal error,
failed hardware. Will restart if error recov-
ers. Integrated control not communicating.
Covers hardware errors (ame sense cir-
cuit faults, pin shorts, etc.).
Hardware problem on the control. Cycle power on control.
Replace if problem prevents service and is persistent. Criti-
cal alert. Cleared 300 seconds after fault recovered.
E126 Control internal communication problem. Hardware problem on the control. Cycle power on con-
trol. Replace if problem prevents service and is persistent.
Cleared 300 seconds after fault recovered.
E131 Corrupted control parameters (Verify con-
guration of system). Communicating only.
Recongure the system. Replace control if heating or cool-
ing is not available. Only applicable in the communicating
mode, not in startup. Exit from Commissioning and Execute
‘Set Factory Default mode Control will still operate on default
parameter settings
E180 Outdoor air temperature sensor failure.
Only shown if shorted or out-of range.
Compare outdoor sensor resistance to temperature/ resis-
tance charts in unit installation instructions. Replace sensor
pack if necessary. At beginning of (any) conguration, furnace
or air handler control will sense outdoor air and discharge
air temperature sensor(s). If detected (reading in range),
appropriate feature will be set as ‘installed’ and that could
be seen in ‘About’ screen. In normal operation after control
recognizes sensors, alarm will be sent if valid temperature
reading is lost. To get rid of setting and alarm, redo congu-
ration and make sure that temperature sensor is marked as
‘not installed’ in Indoor Unit ‘About’ screen. When Indoor unit
control is replaced, thermostat will ‘tell’ new control if tem-
perature sensor is in system or not. Clears 30 seconds after
fault recovered.
E200 Hard lockout - Rollout circuit open or pre-
viously open.
Correct cause of rollout trip, or replace ame rollout switch.
Test furnace operation. Cleared after fault recovered.
E201 Indoor blower communication failure - Un-
able to communicate with blower motor.
Indoor blower communication failure (including power out-
age). Lost communication with indoor blower motor. Possible
causes: motor not powered, loose wiring. Problem may be
on control or motor side. Cleared after fault recovered.
E202 Indoor blower motor mis-match - Indoor
motor horsepower does not match unit ca-
pacity.
Incorrect appliance capacity code selected. Check for proper
conguring under: Unit Size Codes for Furnace/Air Handler
on conguration guide or in installation instructions. Cleared
after the correct match is detected following a reset. (Re-
move thermostat from system while applying power and re-
programming.)
E203 Appliance capacity / size is NOT pro-
grammed. Invalid unit codes refer to con-
guration ow chart.
No appliance capacity code selected. Check for proper con-
guring under: Unit Size Codes for Furnace on conguration
guide or in installation instructions. Critical Alert. Cleared af-
ter valid unit code is read following a reset. (Remove thermo-
stat from system while applying power and reprogramming.)
E204 Gas valve mis-wired. Check gas valve operation and wiring. Clears when repaired.
E205 Gas valve control relay contact shorted. Check wiring on control and gas valve. If wiring is correct,
replace control.

Page 17
TABLE 5 Continued
Ignition Control 103130-05 Diagnostic Codes
Code Diagnostic Codes/Status of Equipment Action Required to Clear and Recover
E206 Gas valve second-stage relay failure Furnace will operate on 1st stage for remainder of the
heating demand. Will clear after fault recovered. If un-
able to operate 2nd stage, replace control.
E207 Hot surface ignitor sensed open. Measure resistance of hot surface ignitor. Replace if
open or not within specied range found in IOM. Re-
sumes normal operation after fault is cleared.
E223 Low pressure switch failed open. Check pressure (inches w.c.) of low pressure switch
closing on heat call. Measure operating pressure (inch-
es w.c.). Inspect vent and combustion air inducer for
correct operation and restriction. Resumes normal op-
eration after fault is cleared
E224 Low pressure switch failed closed. Check operation of low pressure switch to see if it is
stuck closed on heat call longer than 150 seconds. Mea-
sure operating pressure (inches w.c.). Inspect vent and
combustion air inducer for correct operation and restric-
tion. Resumes normal operation after fault is cleared.
E225 High pressure switch failed open. Check pressure (inches w.c.) of high pressure switch
closing on heat call. Measure operating pressure (inch-
es w.c.). Inspect vent and combustion air inducer for
correct operation and restriction. Resumes normal op-
eration after fault is cleared.
E226 High pressure switch failed closed Check operation of high pressure switch closing on heat
call. Measure operating pressure (inches w.c.). Inspect
vent and combustion air inducer for correct operation
and restriction. Resumes normal operation after fault is
cleared.
E227 Low pressure switch open during trial for ignition
or run mode.
Check pressure (inches w.c.) of low pressure switch
closing on heat call. Measure operating pressure (inch-
es w.c.). Inspect vent and combustion air inducer for
correct operation and restriction. Resumes normal op-
eration after fault is cleared.
E228 Combustion air inducer calibration failure Unable to perform pressure switch calibration. Check
vent system and pressure switch wiring connections.
Resumes normal operation after fault is cleared.
E229 Ignition on high re IFC switched to high re ignition because low re pres-
sure switch did not close in allowed time. No action is
needed.
E240 Low ame current - Run mode. Check micro-amperes of ame sensor using control
diagnostics or eld-installed mode. Clean or replace
sensor. Measure voltage of neutral to ground to ensure
good unit ground. Alert clears after current heat call has
been completed.
E241 Flame sensed out of sequence - Flame still pres-
ent.
Shut o󰀨 gas. Check for gas valve leak. Replace, if nec-
essary. Alert clears when fault is recovered.
E250 Limit switch circuit open. Check for proper ring rate on furnace. Ensure there is
no blockage in heater. Check for proper air ow. If limit
not closed within 3 minutes, unit will go into 1-hour soft
lockout. Resumes normal operation after fault is cleared.
E252 Discharge air temperature too high (gas heat only). Check temperature rise, air ow and input rate. Cleared
when heat call is nished.
E270 Soft lockout - Exceeded maximum number of re-
tries. No ame current sensed.
Check for proper gas ow. Ensure that ignitor is lighting
burner. Check ame sensor current. Clears when heat
call nishes successfully.

Page 18
TABLE 5 Continued
Ignition Control 103130-05 Diagnostic Codes
Code Diagnostic Codes/Status of Equipment Action Required to Clear and Recover
E271 Soft lockout - Exceeded maximum number of re-
tries. Last retry failed due to the pressure switch
opening.
Check pressure (inches w.c.) of low pressure switch clos-
ing on heat call. Measure operating pressure (inches w.c.).
Inspect vent and combustion air inducer for correct oper-
ation and restriction. Clears when heat call nishes suc-
cessfully.
E272 Soft lockout - Exceeded maximum number of re-
cycles. Last recycle due to the pressure switch
opening.
Check operation of low pressure switch to see if it is stuck
closed on heat call. Check pressure (inches w.c.) of high
pressure switch closing on heat call. Measure operating
pressure (inches w.c.). Inspect vent and combustion air
inducer for correct operation and restriction. Clears when
heat call nishes successfully.
E273 Soft lockout - Exceeded maximum number of re-
cycles. Last recycle due to ame failure.
Check micro-amperes of ame sensor using control diag-
nostics or eld-installed mode. Clean or replace sensor.
Measure voltage of neutral to ground to ensure good unit
ground. Clears when heat call nishes successfully.
E274 Soft lockout - Exceeded maximum number of re-
cycles. Last recycle failed due to the limit circuit
opening or limit remained open longer than 3 min-
utes
Shut down system. 1-hour soft lockout. Check ring rate
and air ow. Check for blockage. Clears when heat call
nishes successfully.
E275 Soft lockout - Flame sensed out of sequence.
Flame signal is gone.
Shut o󰀨 gas. Check for gas valve leak. 1-hour soft lockout.
Clears when ame has been proven stable.
E276 Watchguard calibration failure. Unable to perform pressure switch calibration. Check vent
system and pressure switch wiring connections. 1-hour soft
lockout. Clears when calibration has nished successfully.
E290 Ignitor circuit fault - Failed ignitor or triggering cir-
cuitry.
Measure resistance of hot surface ignitor. Replace if open
or not within specications. 1-hour soft lockout. Clears
when ame has been proven stable.
E291 Heat air ow restricted below the minimum. Check for dirty lter and air ow restriction. Check blower
performance. 1-hour soft lockout. Cleared when heat call
nishes successfully.
E292 Indoor blower motor unable to start due to ob-
structed wheel, seized bearings.
Indoor blower motor unable to start (seized bearing, stuck
wheel, etc.). Replace motor or wheel if assembly does not
operate or meet performance standards. 1-hour soft lock-
out. Clears after circulator successfully starts.
E294 Combustion air inducer over current. Check combustion blower bearings, wiring and amps. Re-
place if does not operate or does not meet performance
standards. Clears after inducer current is sensed to be in-
range after the ignition following the soft lockout or reset.
E295 Indoor blower motor temperature is too high. Indoor blower motor over temperature (motor tripped on
internal protector). Check motor bearings and amps. Re-
place if necessary. Cleared after blower demand is satis-
ed.
E310 Discharge error temperature sensor failure. Only
shown if shorted or
out of range.
Compare outdoor sensor resistance to temperature/ re-
sistance charts in installation instructions. Replace sensor
if necessary. Cleared in Communicating mode: 30 sec-
onds after fault recovered. In Non- Communicating mode:
Cleared after the current heat call is completed.
E311 Heat rate reduced to match indoor blower air ow. Warning Only. Furnace blower in cutback mode due to
restricted airow. Reduce ring rate every 60 seconds to
match available CFM. Check lter and duct system. To
clear, replace lter if needed or repair/ add duct. 2-stage
controls will reduce ring rate to 1st stage. Clears when
heat call nishes successfully.

Page 19
TABLE 5 Continued
Ignition Control 103130-05 Diagnostic Codes
Code Diagnostic Codes/Status of Equipment Action Required to Clear and Recover
E312 Restricted air ow in cooling or continu-
ous fan mode is lower than cfm setting.
Warning Only. Restricted airow - Indoor blower is running at a re-
duced CFM (Cutback Mode - The variable speed motor has pre-set
speed and torque limiters to protect the motor from damage caused
by operating outside of design parameters (0 to 0.8” W.C.. total ex-
ternal static pressure). Check lter and duct system. To clear, re-
place lter if needed or repair/add duct. Cleared after the current
service demand is satised.
E313 Indoor or outdoor unit capacity mismatch.
Communication only.
Incorrect indoor/outdoor capacity code selected. Check for proper
conguring in installation instructions. Alarm is just a warning. The
system will operate, but might not meet e󰀩ciency and capacity pa-
rameters. Alarm will clear when commissioning is exited. Cleared
after commissioning is complete.
E331 Global network connection - Communica-
tion link problem.
For Future Use.
E334 Relay “Y1” stuck on integrated control. Replace integrated control.
E347 No 24 Volt output on Y1 of ”integrated
control” with non communicating outdoor
unit.
Operation stopped. Y1 relay / Stage 1 failed. (Pilot relay contacts
did not close or the relay coil did not energize; no input back to IFC
chip). Critical Alert. Cleared after reset and Y1 input sensed.
E348 No 24 Volt output on Y2 of ”integrated
control” with non?communicating outdoor
unit.
Y2 relay / Stage 2 failed. (Pilot relay contacts did not close or the
relay coil did not energize; no input back to IFC chip). Critical Alert.
Cleared after reset and Y1 input sensed.
E349 No 24 Volts between R & O on ”integrated
control” with non communicating outdoor
unit (Dual fuel module required for heat
pump application
Conguration link R to O needs to be restored. Replace link or hard-
wire. Applicable in non communicating mode. Critical Alert.
E370 Interlock switch sensed open for 2 min-
utes.
Control sees the loss of 24VAC for 2 minutes. Terminate all services
and wait for interlock switch to close. The alarm will clear when
24VAC is continuously sensed on DS terminal for a minimum of 10
seconds or on a power reset.
E400 LSOM - Compressor internal overload
tripped.
Thermostat demand Y1 is present; but, compressor is not running.
Check power to outdoor unit. Clears the error after current is sensed
in both RUN and START sensors for at least 2 seconds, or after
service is removed, or after power reset.
E401 LSOM Compressor long run cycle or low
system pressure.
Compressor ran more than 18 hours to satisfy a single thermostat
demand. Critical Alert. Clears the error after 30 consecutive normal
run cycles or power reset. Also monitors low pressure switch trips.
E402 LSOM - Outdoor unit system pressure
trip.
Discharge or suction pressure out-of-limits, or compressor over-
loaded. Clears the error after 4 consecutive normal compressor run
cycles.
E403 LSOM - Compressor short-cycling. .(Run-
ning less than 4 minutes). Outdoor unit
pressure trip
Compressor runs less than 3 minutes to satisfy a thermostat de-
mand. Clears the error after 4 consecutive normal run cycles or
power reset.
E404 LSOM - Compressor rotor locked. Com-
pressor short-cycling. (Running less than
4 minutes).
Compressor rotor locked up due to run capacitor short, bearings
are seized, excessive liquid refrigerant, etc. Clears the error after 4
consecutive normal run cycles or after power reset.
E405 LSOM - Compressor open circuit. Compressor circuit open (due to power disconnection, open fuse,
etc.) Clears the error after 1 normal compressor run cycle.

Page 20
TABLE 5 Continued
Ignition Control 103130-05 Diagnostic Codes
Code Diagnostic Codes/Status of Equipment Action Required to Clear and Recover
E406 LSOM - Compressor open start circuit. Required amount of current is not passing through Start cur-
rent transformer. Clears the error after current is sensed in
START sensor, or after power reset.
E407 LSOM - Compressor open run circuit. Required amount of current is not passing through Run current
transformer. Clears the error after current is sensed in RUN
sensor, or 1 normal compressor run cycle, or after power reset.
E408 LSOM - Compressor contactor is welded. Compressor runs continuously. Clears the error after 1 normal
compressor run cycle or after power reset.
E409 LSOM - Compressor low voltage. Secondary voltage is below 18VAC. After 10 minutes, oper-
ation is discontinued. Clears the code after voltage is higher
than 20 VAC for 2 seconds or after power reset.