Lennox International Inc. EL280DF manual

Page 1 08/12 *2P0812* 506896−01 *P506896-01* E 2012 Lennox Industries Inc. Dallas, T exas, USA DOWNFLOW AIR FLOW INST ALLA TION INSTRUCTIONS EL280DF MERIT ® SERIES GAS FURNACE DOWNFLOW AIR DISCHARGE 506896−01 08/2012 This is a safety alert symbol and should never be ignored. When you see this symbol on labels or in manuals, be alert to the pot[...]

Page 2 Unit Dimensions − inches (mm) 1 − 1/2 (38) Front Panel GAS PIPING INLET (Either Side) FLUE OUTLET (T op) ELECTRICAL INLET (Either Side) RETURN AIR OPENING TOP VIEW A B C D 3/4 (19) 27 − 3/4 (705) 19 − 1/4 (489) 6 − 5/8 (168) Right 7 − 1/8 (181) Left 5 − 3/8 (137) Right 2 − 3/16 (56) Left 33 (838) AIR FLOW 19 − 7/16 (494) 9/[...]

Page 3 EL280DF Gas Furnace The E L280DF g as furnace i s s hipped r eady f or i nstallation in the downflow position f ueled b y natural gas. A conver- sion k it ( ordered sep arately) is required for u se in L P/Pro- pane gas applications. Shipping and Packing List Package 1 of 1 cont ains 1 − Assembled EL280DF unit 1 − Bag assembly containing[...]

Page 4 FIGURE 1 AIR HANDLER GAS UNIT Dampers (open during cooling operation only) Dampers (open during heating operation only) When i nstalled, t his f urnace m ust be e lectrically grounded according t o l ocal c odes. I n a ddition, i n t he U nited S tates, installation must conform with the current National Elec- tric C ode, A NSI/NFP A N o. 70[...]

Page 5 W ARNING Th e S tat e of California has determined that this prod- uc t may contain or produce a chemical or chemicals, in very low doses, which may cause serious illness or death. It may also cause cancer , birth defect s o r re - productive harm. Combustion, Dilution & V entilation Air In t he p ast, t here w as n o p roblem i n b ring[...]

Page 6 Confined Sp ace A confined space is an area with a volume less than 50 cu- bic feet (1.42 m 3 ) per 1,000 Btu (.29 kW) per hour of the combined input rating of all appliances installed in that space. This definition includes furnace closets or small equipment rooms. When the furnace is installed so that supply ducts carry air circulated b y [...]

Page 7 EQUIPMENT IN CONFINED SP ACE ALL AIR FROM OUTSIDE (Inlet Air from Crawlspace and Outlet Air to V entilated Attic) NOTE−The inlet and outlet air openings shall each have a free area of at least one square inch (645 mm 2 ) per 4,000 Btu (1.17 kW) per hour of the tot al input rating of all equipment in the enclosure. VENTILA TION LOUVERS (Eac[...]

Page 8 Downflow Installation Downflow unit installs in three ways: on non−combustible flooring, on combustible flooring using a downflow com- bustible flooring base, or on a reverse−flow cooling cabinet. Do not drag the unit across the floor . Inst allation on Non−Combustible Flooring (Figure 6) 1 − Cu t floor opening keeping in mind cleara[...]

Page 9 EL280DF UNIT COOLING COIL PLENUM FIGURE 8 PROPERL Y SIZED FLOOR OPENING Return Air Opening −− Downflow Unit s The following steps should be taken when inst alling ple- num: 1 − Bottom edge of plenum should be flanged with a hemmed edge (See figure 9). SECURE FROM OUTSIDE CABINET HEMMED EDGE PLENUM SEALING STRIP (Field Provided) CABINET[...]

Page 10 FIGURE 12 Front Back Horizont al Downflow Application Allow for clearances to combustible materials as indicated on t he unit n ameplate. Minimum c learances for c loset or a l- cove installations are shown in figure 13. Downflow Application Installation Clearances To p Bottom Left Side Right Side T ype of V ent Connector T ype C T ype B1 T[...]

Page 1 1 Duct System Use industry-approved standards (such as those pub- lished by Air Conditioning Contractors of America or Ameri- can Society of Heating, Refrigerating and Air Conditioning Engineers) to siz e and install the supply and return air duct system. This will result in a quiet and low-st atic system that has uniform air distribution. N[...]

Page 12 FIGURE 15 Common V enting Using Tile−Lined Interior Masonry Chimney and Combined V ent Connector MINIMUM LENGTH = AS SHORT AS PRACTICAL. FOR MAXIMUM LENGTH SEE NOTE TO LEFT INTERIOR TILE−LINED MASONRY CHIMNEY NOTE − the chimney must be properly sized per provided venting tables or lined with listed metal lining system. PERMANENTL Y SE[...]

Page 13 Never connect a Category I appliance to a chimney that is servicing a solid−fuel appliance. If a fireplace chimney flue is used to vent this appliance, the fireplace opening must be permanently sealed. A type B or listed chimney lining system that passes through an unused masonry chimney flue is not considered to be exposed to the outdoor[...]

Page 14 19 − I n no case, shall the vent connector be sized more than two consecutive table size diameters over the size of the draft hood outlet or flue collar outlet. 20 − Do not install a manual damper , barometric draft regu- lator or flue restrictor between the furnace and the chimney . 21 − When connecting this appliance to an existing [...]

Page 15 T ABLE 6 V ent Connector Capacity T ype B Double−W all V ents with T ype B Double−W all Connectors Serving T wo or More Category I Appliances V ent Height H (feet) Connector Rise R (feet) V ent and Connector Diameter − D (inches) 3 Inch 4 Inch 5 Inch 6 Inch Appliance Input Rating in Thousands of Btu Per Hour MIN MAX MIN MAX MIN MAX MI[...]

Page 16 Removal of the Furnace from Common V ent In the event that an existing furnace is removed from a venting system commonly run with separate gas ap- pliances, the venting system is likely to be too large to properly vent the remaining attached appliances. Conduct t he f ollowing test while each a ppliance i s operat- ing a nd the o t her appl[...]

Page 17 T ABLE 8 Gas Pipe Cap acity − f t 3 /hr (m 3 /hr) Nominal Iron Pipe Size inches (mm) Internal Diameter inches (mm) Length of Pipe − feet (m) 10 (3.048) 20 (6.096) 30 (9.144) 40 (12.192) 50 (15.240) 60 (18.288) 70 (21.336) 80 (24.384) 90 (27.432) 100 (30.480) 1/2 (12.7) .622 (17.799) 172 (4.87) 11 8 (3.34) 95 (2.69) 81 (2.29) 72 (2.03) 6[...]

Page 18 Leak Check After gas piping is completed, carefully check all piping connections (f act ory− and field−installed) for gas leaks. Use a leak detecting solution or other preferred means. NOTE − I f emergency shutoff is necessary , shut off the main manual gas valve and disconnect the main power to the furnace. The installer should prope[...]

Page 19 of the circuit being connected to one of the provided neutral terminals. If an accessory rated at greater than one amp is connected to this terminal, it is necessary to use an exter- nal relay . On e line voltage HUM" 1/4" spade terminnal is provided on the furnace integrated control. See figure 2 1 for integrated control confi[...]

Page 20 T ABLE 9 Field Wiring Applications Thermost at DIP Switch Settings and On−Board Links (See figure 21) Wiring Connections DIP Switch 1 W915 T wo−St age Cooling W951 Heat Pump s 1 Heat / 1 Cool NO TE − Us e DIP switch 2 to set sec - ond−stage heat ON delay . OFF10 minutes. ON−15 minutes. ON Intact Intact S1 T’STAT CONTROL TERM. ST[...]

Page 21 T ABLE 9 Field Wiring Applications (Continued) Thermost at DIP Switch Settings and On−Board Links (See figure 21) Wiring Connections DIP Switch 1 W915 T wo−St age Cooling W951 Heat Pump s 2 Heat / 2 Cool OFF Cut Intact S1 T’STAT CONTROL TERM. STRIP OUTDOOR UNIT 2 Heat / 1 Cool OFF Intact Intact S1 T’STAT CONTROL TERM. STRIP OUTDOOR [...]

Page 22 FIGURE 2 0 EL280DF Schematic Wiring Diagram[...]

Page 23 Integrated Control FIGURE 21 TWO−ST AGE INTEGRA TED CONTROL THERMOST A T CONNECTIONS (TB1) 1/4" QUICK CONNECT TERMINALS DIP SWITCH FUNCTIONS DIP SWITCHES DIAGNOSTIC LEDs ON−BOARD LINKS 1= ERROR CODE RECALL H= 24V HUMIDIFIER OUTPUT L= LENNOX SYSTEM OPERA TION MONITOR SENSE = 120 V AC OUTPUT TO FLAME SENSER NEUTRALS= 120 V AC NEUTRAL[...]

Page 24 settings provide lower supply air temperatures; shorter set- tings provide higher supply air temperatures.T able 10 pro- vides the blower off timings that will result from dif ferent switch settings. T ABLE 10 Heating Blower−Off Delay Switch Settings Blower Off Delay (Seconds) Switch 3 Switch 4 60 Off On 90 (factory setting) Of f Off 120 [...]

Page 25 FIGURE 22 GAS V AL VE SHOWN IN ON POSITION INLET PRESSURE POST HIGH FIRE ADJUSTMENT SCREW (under cap) MANIFOLD PRESSURE T AP 8 − M ov e switch on gas valve to ON . Do not force. See fig- ure 2 2. 9 − Replace the upper access panel. 10− Turn on all electrical power to to the unit. 1 1− Set the thermostat to desired setting. NOTE − [...]

Page 26 Proper Combustion Furnace should operate minimum 15 minutes with correct manifold pressure and gas flow rate before checking com- bustion. T able 12 shows acceptable combustion for ALL EL280DF models. The maximum carbon monoxide reading should not exceed 50 ppm T ABLE 12 Firing Rate CO 2 % For Nat CO 2 % For L.P . High Fire 6 .8 − 7. 4 7.[...]

Page 27 Other Unit Adjustment s Primary and Secondary Limit s The primary limit is located on the heating compartment vestibule panel. The secondary limits (if equipped) are lo- cated in th e bl ower comp artment, att ached to the back side of the blower . These auto reset limits are factory−set and re - quire no adjustment. Flame Rollout Switche[...]

Page 28 Heating Sequence of Operation When there is a call for heat, the integrated control runs a self check. The control checks for S10 primary limit, S21 secondary limit (s) and S47 rollout switch normally closed contact s. The control also checks for S102 high heat and S128 low heat prove switch normally open contact s. Once self check is compl[...]

Page 29 Service W ARNING ELECTRICAL SHOCK, FIRE, OR EXPLOSION HAZARD. Failure to follow safety warnings exactly could result in dangerous operation, serious injury , death or property damage. Improper servicing could result in dangerous opera- tion, serious injury , death, or property damage. Before servicing, disconnect all electrical power to fur[...]

Page 30 EL280DF BURNER, COMBUSTION AIR INDUCER ASSEMBL Y & HEA T EXCHANGER REMOV AL FIGURE 24 burners burner box assembly manifold and gas valve retention rings cross over Rep air Part s List The following repair part s are available through indepen- dent Lennox dealers. When ordering parts, include the complete fu r nace model number listed on[...]

Page 31 St art−Up & Performance Check List Unit Model Number_______________ Serial Number___________________ UNIT SET UP (typical) Gas Supply Pressure 1 2 2 1 SUPPL Y AIR Line V oltage 3 4 5 Filter RETURN AIR RETURN AIR GAS SUPPL Y Natural Gas LP/Prop ane Gas Piping Connections Tight Leak T ested Supply Line Pressure  W .C.________ 1 VENT [...]

Page 32 Contractor’s: Name_________________________T elephone_____________Checklist Completed____________________ Job Address_____−________________________________T echnician’s Name___________________________________ UNIT OPERA TION (typical) 1 HEA TING MODE GAS MANIFOLD PRESSURE W .C._____ COMBUSTION SAMPLE CO 2 % ______ CO PPM_______ 2 I[...]