Lennox EL280UHE Series Service Literature
  1. Manuals
  2. Brands
  3. Lennox Manuals
  4. Furnace
  5. EL280UHE
  6. Service literature

Lennox EL280UHE Series Service Literature

Hide thumbs Also See for EL280UHE Series:

Advertisement

Table of Contents

S e r v i c e L i t e r a t u r e
EL280UHE(X) series units are 80% efficiency gas furnac-
es used for upflow or horizontal applications only, manu-
factured with Lennox Duralok heat exchangers formed of
aluminized steel. 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. EL280UHE(X)
model units are equipped with the SureLight® two-stage
integrated control. EL280UHE(X) unit meets the California
Nitrogen Oxides (NOx) Standards and California Season-
al Efficiency requirements. All units use a redundant gas
valve to assure safety shut-off as required by C.S.A.
All specifications 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

Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 2
Blower Performance Data . . . . . . . . . . . . . . . . . . Page 5
Parts Identification. . . . . . . . . . . . . . . . . . . . . . . . Page 7
I Unit Components . . . . . . . . . . . . . . . . . . . . . . . . Page 8
II Installation . . . . . . . . . . . . . . . . . . . . . . . . . . Page 25
III Start Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 25
IV Heating System Service Checks . . . . . . . . . Page 25
V Typical Operating Characteristics . . . . . . . . . Page29
VI Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . Page 30
IX Troubleshooting Flow Chart . . . . . . . . . . . . . Page 41
UNIT INFORMATION
UNIT INFORMATION
Corp 1901-L1
EL280UHE(X) SERIES UNITS
Page 1
C C C C
I I I I
HI
HI
WARNING
Improper
installation,
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.
WARNING
Electric shock hazard. Can cause injury or death.
Before attempting to perform any service or
maintenance, turn the electrical power to unit OFF
at disconnect switch(es). Unit may have multiple
power supplies.
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.
EL280UHE(X)
adjustment,
alteration,
©2016 Lennox Industries, Inc.

Advertisement

Table of Contents
loading

Related Manuals for Lennox EL280UHE Series

Summary of Contents for Lennox EL280UHE Series

  • Page 1: Table Of Contents

    EL280UHE(X) series units are 80% efficiency gas furnac- es used for upflow or horizontal applications only, manu- factured with Lennox Duralok heat exchangers formed of aluminized steel. Units are available in heating capacities of 44.000 to 110,000 Btuh and cooling applications up to 5 tons.

  • Page 2: Specifications

    SPECI FICATIONS Model No. EL280UH045E36A EL280UH070E36A Heating Model No. - Low NOx - - - EL280UH070XE36A Performance AFUE High Input - Btuh 44,000 66,000 Fire Output - Btuh 35,000 53,000 Temperature rise range - °F 30 - 60 30 - 60 Gas Manifold Pressure (in.
  • Page 3 SPECIFI CAT IONS Model No. EL280UH110E48C EL280UH110E60C Heating Model No. - Low NOx - - - EL280UH110XE60C Performance AFUE High Input - Btuh 110,000 110,000 Fire Output - Btuh 86,000 87,000 Temperature rise range - °F 35 - 65 30 - 60 Gas Manifold Pressure (in.
  • Page 4 O PTI ONAL A CCE SSORIES - ORDER SEPAR AT ELY “A” Width “B” Width “C” Width Models Models Models CABINET Horizontal Suspension Kit - Horizontal only 51W10 51W10 51W10 Return Air Base - Upflow only 65W75 50W98 50W99 High Performance Economizer (Commercial only) 10U53 10U53 10U53...
  • Page 5 EL280UH045E36A PERFORMANCE (Less Filter) Air Volume / Watts at Various Blower Speeds External Static High Medium-High Medium Medium-Low Pressure (Black) (Brown) (Blue) (Yellow) (Red) in. w.g. Watts Watts Watts Watts Watts 0.00 1500 1220 1050 0.10 1485 1200 1025 0.20 1460 1170 0.30...
  • Page 6 EL280UH090E48B PERFORMANCE (Less Filter) Air Volume / Watts at Various Blower Speeds External Static High Medium-High Medium Medium-Low Pressure (Black) (Brown) (Blue) (Yellow) (Red) in. w.g. Watts Watts Watts Watts Watts 0.00 1800 1555 1425 1370 1240 0.10 1765 1525 1390 1320 1190...
  • Page 7 EL280UHE(X) Parts Arrangement Make Up Box Heat Exchanger Combustion Air Inducer Combustion Air Pressure Switch Gas Valve and Manifold Assembly Collector Box Indoor Blower and Motor Assembly (installed in cabinet) Limit Switch (under collector box) Constant Torque Indoor Blower Motor (removed from cabinet) Two-Stage Integrated Control Figure 1...

  • Page 8: I Unit Components

    I-UNIT COMPONENTS 3. Circuit Breaker (CB8) A 24V circuit breaker is also located in the control box. EL280UHE(X) unit components are shown in figure 1. The The switch provides overcurrent protection to the trans- gas valve, combustion air inducer and burners can be ac- former (T1).
  • Page 9 After the 15-second pre-purge period, the SureLight ® TABLE 1 nitor warms up for 20 seconds after which the gas valve SureLight Control 5 Pin Terminal Designation ® opens for a 4-second trial for ignition. The ignitor remains Pin # Function energized during the trial until flame is sensed.
  • Page 10 INTEGRATED CONTROL 24VAC Indoor Ignitor and Combustion Blower Terminals Air Inducer Neutrals Flame Sense S4 DIP Switches Diagnostic Push Button On Board Links THERMOSTAT CONNECTIONS (TB1) 3/16” QUICK CONNECT TERMINALS DS = DEHUMIDIFICATION SIGNAL FLAME SENSE SIGNAL W2 = HEAT DEMAND FROM 2ND STAGE T/STAT HI COOL 24VAC W1 = HEAT DEMAND FROM 1ST STAGE T/STAT HI HEAT 24VAC...
  • Page 11 INTEGRATED CONTROL CONFIGURATION GUIDE 2ND STAGE HEAT ON DELAY 7 MIN UPSTAGE THERMOSTAT SELECTION DELAY COOLING BLOWER-OFF DELAY TWO STAGE THERMOSTAT 12 MIN UPSTAGE *45 SECOND COOL BLOWER DELAY 1−STAGE OFF DELAY THERMOSTAT (TIMED STAGING) −SEE SW #2 HSI/CAI 2 SECOND COOL BLOWER HEATING BLOWER−OFF DELAY OFF DELAY...
  • Page 12 TABLE 3 Integrated Control Diagnostic Modes Display Action (when button released) No Change Remain in idle mode Solid “E” Enter diagnostic recall mode Solid “F” Enter flame signal mode TABLE 4 Integrated Diagnostic Codes/Status of Equipment 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).
  • Page 13 TABLE 4 Continued Code Diagnostic Codes/Status of Equipment Action Required to Clear and Recover E125 Control failed self-check, internal error, Hardware problem on the control. Cycle power on control. Replace failed hardware. Will restart if error recovers. if problem prevents service and is persistent. Critical alert. Cleared Integrated control not communicating.
  • Page 14 TABLE 4 Continued Code Diagnostic Codes/Status of Equipment Action Required to Clear and Recover E270 Soft lockout - Exceeded maximum number of Check for proper gas flow. Ensure that ignitor is lighting burner. retries. No flame current sensed. Check flame sensor current. Clears when heat call finishes successfully.
  • Page 15 Integrated Control DIP Switches TABLE 5 EL280UHE(X) units are equipped with a two-stage inte- Blower Off Heating Mode Delay Switch Settings grated control. This control manages ignition timing, heat- Blower Off Delay ing mode fan off delays and indoor blower speeds based Switch 3 Switch 4 Seconds...
  • Page 16 B- Indoor Blower BLOWER WHEEL REPLACEMENT IMPORTANT Center Blower Wheel Each blower is statically and dynamically balanced in Blower Housing as an assembly before installation in the unit. EL280UHE(X) units are equipped with a constant torque ECM motor. It has a DC motor coupled to an electronicco- ntrol module both contained in the same motor housing.
  • Page 17 Multi−Meter (set to VAC) Multi−Meter (set to VAC) Test 1 Test 3 (if necessary) Turn on power to unit. Check for 120 volts across terminals Check for 120 volts across terminals “L1” and “Neutrals” on “L” and “N” on input plug P48. If voltage is present continue the integrated control.
  • Page 18 Replacing the Motor Module Motor Test 1 - Disconnect electrical power to unit. 2 - Remove unit access panel. 3 - Unplug the two harnesses from the motor control module. See figure 9. 4 - Remove the two hex head bolts securing the motor control module to the motor (see figure 10).
  • Page 19 The switch may have a different set point for each unit wire harness connects the terminals from the gas valve to model number. See Lennox Repair Parts Handbook if limit the electronic ignition control. 24V applied to the terminals switch must be replaced.
  • Page 20 HEATING COMPONENTS Ignitor Burners Rollout Switch Sensor Gas Valve Manifold and Gas Orifices FIGURE 13 Page 20...
  • Page 21 To Measure Flame Signal - Integrated Control: 6 - Turn supply voltage on and close thermostat contacts to cycle system. Use a digital readout meter capable of reading DC micro- 7 - When main burners are in operation for two minutes, amps.
  • Page 22 EL280UHE(X) Ignitor Check Out Test 1 Checking resistance of ignitor circuit Remove 5-pin plug from integrated control. Check Ohms reading across terminal 1 and 5. Reading should be between 39 and 70 ohms. If value is correct, this is the only test needed. If the meter reading is not correct (”0”...
  • Page 23 A bleed port on the switch allows relatively NOTE - Each furnace model uses a unique CAI. Refer to dry air in the vestibule to purge switch tubing, to prevent Lennox Repair Parts listing for correct inducer for replace- condensate build up. ment.
  • Page 24 Multiple Venting screws, rotate the combustion air inducer and gasket (pressure switch should be above the combustion air in- The EL280UHE(X) furnace can vent in multiple positions. ducer in all positions), then reinstall the mounting screws. See figure 17. See unit Installation Instructions for more detail. The make up box may be removed and the combustion IMPORTANT air inducer may be rotated clockwise or counterclockwise...

  • Page 25: Installation

    II-PLACEMENT AND INSTALLATION NOTE - When unit is initially started, steps 1 through 11 may need to be repeated to purge air from gas line. Make sure unit is installed in accordance with installation Turning Off Gas To Unit instructions and applicable codes. 1 - Set thermostat to lowest setting.
  • Page 26 Use of a specialty Gas Leak Detector is strongly recommended. It TABLE 12 is available through Lennox under part number 31B2001. GAS METERING CLOCKING CHART See Corp. 8411-L10, for further details. Natural 1000 btu/...
  • Page 27 G- Proper Combustion H- High Altitude Furnace should operate minimum 15 minutes with correct The manifold pressure may require adjustment and com- manifold pressure and gas flow rate before checking com- bustion air pressure switch may need replacing to ensure bustion.
  • Page 28 I- Proper Ground and Voltage 2 - In addition, measure the AC voltage from Line Hot to Line Neutral (spade terminals) on the integrated Furnace must be properly grounded for proper perfor- control. See figure 20. This voltage should be in the mance.

  • Page 29: Typical Operating Characteristics

    V-TYPICAL OPERATING CHARACTERISTICS C-External Static Pressure 1 - Tap locations shown in figure 22. A-Blower Operation and Adjustment 2 - Punch a 1/4” diameter hole in supply and return 1 - Blower operation is dependent on thermostat control air plenums. Insert manomter hose flush with system.

  • Page 30: Maintenance

    At the beginning of each heating season, and to comply provide combustion air. with the Lennox Limited Warranty, your system should be checked by a licensed professional technician (or equiva- 10 - Inspect the furnace venting system to make sure...
  • Page 31 Cleaning the Heat Exchanger and Burners 12 - To clean burners, run a vacuum cleaner with a soft brush attachment over the face of burners. Visually NOTE - Use papers or protective covering in front of the inspect inside the burners and crossovers for any furnace during cleaning.
  • Page 32 BURNER, COMBUSTION AIR INDUCER ASSEMBLY & HEAT EXCHANGER REMOVAL Gasket Pressure Switch Flue Transition Collector Box Heat Exchanger Ignitor Orifice Plate Combustion Air Inducer Retention Rings Rollout Switches Sensor Cross Over Manifold And Gas Valve FIGURE 23 Remove 5 screws if necessary EL280UHE(X) NOx INSERTS (either side of cabinet) NOx Insert...

  • Page 33: Wiring And Sequence Of Operation

    VII- Wiring and Sequence of Operation EL280UH(X)E Schematic Wiring Diagram FIGURE 26 Page 33...
  • Page 34 Electronic Ignition When the delay ends, the indoor blower motor is ener- gized on the low fire heating speed, the HUM contacts The two-stage integrated control used in EL280UHE(X) close energizing the humidifier and 120V ACC terminal units has an added feature of an internal Watchguard is energized.
  • Page 35 Applications Using A Single-Stage Thermostat 4 - After the 20-second warm-up period has ended, the gas valve is energized on low fire (first stage) See figure 27 for ignition control sequence and ignition occurs. At the same time, the control B - Heating Sequence -- Integrated Control Thermostat module sends a signal to begin an indoor blower Selection DIP Switch 1 ON in “Single-Stage”...

  • Page 36: Field Wiring And Dip Switch Settings

    VIII- Field Wiring and DIP Switch Settings TABLE 17 DIP Switch Settings and On-Board Links DIP Switch 1 On Board Links Must Be Cut To Select Thermostat Thermostat Wiring Connections System Options Heating Stages 1 Heat / 1 Cool FURNACE OUTDOOR T'STAT TERM.
  • Page 37 TABLE 17 Continued DIP Switch Settings and On-Board Links DIP Switch 1 On Board Links Must Be Cut To Select Thermostat Thermostat Wiring Connections System Options Heating Stages 2 Heat / 2 Cool FURNACE OUTDOOR T'STAT TERM. STRIP UNIT CUT ON-BOARD LINK W915 2 STAGE COMPR...
  • Page 38 TABLE 17 Continued DIP Switch Settings and On-Board Links DIP Switch 1 Thermostat On Board Links Must Be Cut To Select Wiring Connections Thermostat Heating System Options Stages Dual Fuel FURNACE HEAT PUMP T'STAT TERM. STRIP Single Stage Heat Pump CUT ON-BOARD LINK ComfortSense W951...
  • Page 39 TABLE 17 Continued DIP Switch Settings and On-Board Links DIP Switch 1 Wiring Connections Thermostat On Board Links Must Be Cut To Select Thermostat Heating System Options Stages Dual Fuel FURNACE HEAT PUMP T'STAT TERM. STRIP Single Stage Heat Pump CUT ON-BOARD LINK ComfortSense W951...
  • Page 40 IX- Troubleshooting HEATING SEQUENCE OF OPERATION NORMAL AND ABNORMAL HEATING MODE POWER ON GAS VALVE OFF. COMBUSTION AIR INDUCER OFF. INDOOR BLOWER OFF. (RESET CONTROL BY CONTROL SELF-CHECK OKAY? TURNING MAIN POWER OFF.) POLARITY REVERSED. POLARITY OKAY? STATUS ERROR CODE 5 + 4. IS THERE A SIGNAL HOLDS UNTIL UNIT IS PROPERLY GROUNDED.
  • Page 41 HEATING SEQUENCE OF OPERATION CONTINUED THERMOSTAT CALLS FOR HEAT STATUS LED - HEARTBEAT. (Refer to box A on previous page) GAS VALVE OFF. COMBUSTION AIR INDUCER FIRST-STAGE (LOW FIRE) PRESSURE OFF. INDOOR BLOWER OFF. UNIT WILL RETRY SWITCH CLOSED WITHIN 2.5 MINUTES? AFTER 5-MINUTE WAIT PERIOD.
  • Page 42 HEATING SEQUENCE OF OPERATION CONTINUED THERMOSTAT CALLS FOR HEAT. STATUS LED -- HEARTBEAT. SEE BOX A. FLAME SIGNAL ABOVE ( 1.40 microamps) LOW FLAME SIGNAL (Does not affect control operation) STATUS ERROR CODE 1 + 2. SINGLE-STAGE THERMOSTAT MODE TWO STAGE THERMOSTAT MODE (DIP SWITCH SET AT “ON”) (DIP SWITCH SET AT “OFF”) START SECOND-STAGE RECOGNITION...
  • Page 43 HEATING SEQUENCE OF OPERATION CONTINUED SEE BOX A NORMAL OPERATION. SEE BOX B THERMOSTAT CALLS FOR HEAT. RETURN TO FIRST-STAGE HEAT MODE. FIRST-STAGE CONTINUES UNTIL SECOND- STAGE PRESSURE SWITCH CAN BE PROVEN SECOND-STAGE (HIGH FIRE) HEAT or HEAT DEMAND IS SATISFIED. A FIVE (5) PRESSURE SWITCH CLOSED? MINUTE WAIT PERIOD IS INITIATED BEFORE RETRY.
  • Page 44 COOLING SEQUENCE OF OPERATION POWER ON SIGNAL POLARITY REVERSED. CONTROL WILL CONTINUE TO CALL FOR COOLING IS POLARITY REVERSED? IN THIS CONDITION. STATUS ERROR CODE 5 + 4. SIGNAL IMPROPER GROUND AT LED. CONTROL WILL CONTINUE TO CALL FOR COOLING IS THERE IN THIS CONDITION.
  • Page 45 CONTINUOUS LOW SPEED FAN SEQUENCE OF OPERATION MANUAL FAN SELECTION MADE AT THERMOSTAT. AFTER 2 SECOND DELAY, INDOOR BLOWER IS ENERGIZED ON CONTINUOUS FAN SPEED. THERMOSTAT CALLS FOR FIRST STAGE COOL. THERMOSTAT CALLS FOR FIRST-STAGE HEAT. INDOOR BLOWER RAMPS TO FIRST STAGE AFTER 45-SECOND DELAY, INDOOR BLOWER COOLING SPEED AFTER A 2-SECOND DELAY.

This manual is also suitable for:

El280uh045e36aEl280uh070e36aEl280uh070xe36aEl280uh090e36bEl280uh090e48bEl280uh090xe48b ... Show all

Table of Contents