INSTALLATION Litho U.S.A. INSTRUCTIONS

1 506682 01*P506682-01*E 2011 Lennox Industries , Texas, USAL itho ,000 to 400,000 Btuh SeriesUNIT HEATERS506682 015/2011 Supersedes 503,523 MTable Of ContentsLF24 Unit Dimensions 1.. Shipping 2.. Optional Accessories 2.. CSA Requirements in USA 3.. CSA Requirements in Canada 3.. Additional Requirements 3.. Unit Heater INSTALLATION 3.. Combustion and Ventilation Air 4.. Rotation of Combustion Air Inducer 5.. Venting 5.. Electrical Connections10.. Typical LF24 Wiring Diagram10.. Gas Connection11.. Leak Check11.. RETAIN THESE INSTRUCTIONSFOR FUTURE REFERENCEUnit Start Up11.

2 To Turn Off Gas to Unit13.. Heating Sequence of Operation13.. Ignition Control LED13.. High Altitude Adjustment13.. Gas Flow15.. Gas Pressure Adjustment15.. Limit Control Switch15.. Louver Vane Adjustments15.. Combustion Air Pressure Switch15.. Service15.. Start Up and Performance Checklist16.. Template17.. WHAT TO DO IF YOU SMELL GAS:Do not store or use gasoline or otherflammable vapors and liquids in the vi-cinity of this or any other and service must be per-formed by a qualified installer, serviceagency or the gas not try to light any the building not touch any electrical switch; do not useany phone in your call your gas supplier from aneighbor s phone.

3 Follow the gas supplier s you cannot reach your gas supplier, call thefire OR EXPLOSION to follow safety warnings exact-ly could result in serious injury, death,or property sure to read and understand theinstallation, operation and service in-structions in this INSTALLATION , adjustment, alter-ation, service or maintenance can causeserious injury, death or property 1LF24 Unit Dimensions1/2 (13)TOP VIEWSIDE VIEWADJUSTABLELOUVERSGASVALVEHEATEXCHANG ERDIRECTDRIVE FANFLUEOUTLETELECTRICAL INLETS3/8" x 16 MOUNTING NUTSFOR UNIT SUSPENSIONAIRFLOWCOMBUSTION AIRINDUCEREND VIEWABCEFGNOTE LF24 models 100, 115, 145, 175 and200 have a single fan.

4 LF24 models 230, 250, 300,345 and 400 have two *7-5/8(194)1/2 (13)Additionalmounting nutsfurnished onLF 230,LF24 250,LF24 300,LF24 345 andLF24 400 Two mounting nuts are furnished onLF24 models 100, 115, 145, 175 and 200. Fourmounting nuts are furnished on LF24 models230, 250, 300, 345 and 400 14531-5/1679532-3/1681720-3/1651211-1/22 9219-1/1648411-3/42983-1/4837-7/8200LF24 175LF24 20031-5/1679532-3/1681723-1/858811-1/229 222-1/165608 1/22163-1/4838 11/16220LF24-230*LF24 250*LF24 300*31-5/1679532-3/1681741-1/810453-11/1 69740101617-3/44513-1/2898-11/16220LF24- 345*LF24 400*31-5/1679532-3/1681741-1/810453-11/1 69740101617-1/24453-1/2899-13/16248*Unit contains dual heater is completely assembled and is shipped with INSTALLATION and operating INSTRUCTIONS .

5 Warranty certificate andflue transition. Check the unit for shipping damage. The receiving party should contact the last carrier immediately if anyshipping damage is 2 Optional AccessoriesTABLE 1LF24 100 to LF24 230 GasHeatingPerformanceModel No. Stainless SteelLF24 100 SLF24 115 SLF24 145 SLF24 175 SLF24 200 SModel No. Aluminized SteelLF24 100 ALF24 115 ALF24 145 ALF24 175 ALF24 200 AOptional Accessories Must Be Ordered ExtraDischargeNozzle30_ 94K94 SSS30_ 94K95SS45_ 95K98 SSS45_ 95K99SS60_ 16L28 SSS60_ 16L29SS90_ 15L96 SSS90_ 15L97 SSHanging BracketKit87277 SSSSSHigh AltitudePressure SwitchKit10K73S1S1S1S2 LPG/Propane Kit45L85S63J56 SSS20L07S63J571 LF24 100 through 145 require replacement combustion air inducer pressure switch at altitudes over 5500 feet above sea LF24 175 requires replacement combustion air inducer pressure switch

6 At altitudes over 2500 feet above sea 2LF24 230 to LF24 400 GasHeatingPerformanceModel No. Stainless SteelLF24 230 SLF24 250 SLF24 300 SLF24 345 SLF24 400 SModel No. Aluminized SteelLF24 230 ALF24 250 ALF24 300 ALF24 345 ALF24 400 AOptional Accessories Must Be Ordered ExtraDischargeNozzle30_ 94K96 SSSSS45_ 95K00 SSSSS60_ 16L30 SSSSS90_ 15L98 SSSSSH anging BracketKit87277 SSSSSLPG/Propane Kit45L88SS63J57SS20L06 SPage 3 CSA Requirements in USAI nstallation of gas unit heaters must conform with localbuilding codes or, in the absence of local codes, with thecurrent edition of ANSI , National Fuel Gas in aircraft hangers must be in accordance withthe current edition of ANSI/NFPA No.

7 409, Standard forAircraft in parking structures must be in accordancewith the current edition of ANSI/NFPA No. 88A, Standardfor Parking in repair garages must be in accordance withthe current edition of ANSI/NFPA No. 88B, Standard forRepair having jurisdiction should be consulted beforeinstallation. Air for combustion and ventilation mustconform to the methods outlined in the current edition ofANSI , Section , Air for Combustion andVentilation, or applicable provisions of local National Fuel Gas Code (ANSI ) is availablefrom:American National Standard Institute West 42nd StreetNew York, NY 10036 These units are CSA international design certified.

8 Theseunit heaters are certified for clearances to combustiblematerial as listed in table 1 and on unit rating and service clearances must be observed inaddition to fire protection electrical wiring and grounding for unit must be inaccordance with the regulations of the current edition ofANSI/NFPA No. 70, National Electric National Electric Code is available from:National Fire Protection Association1 Batterymarch ParkPO Box 9101 Quincy, MA 02269 9101 CSA Requirements in CanadaThese INSTRUCTIONS are intended only as a general guideand do not supersede local codes in any way.

9 Authoritieshaving jurisdiction should be consulted beforeinstallation. The INSTALLATION must conform with localbuilding codes or, in the absence of local codes, with thecurrent edition of CSA B149 INSTALLATION compliancecodes. All electrical wiring and grounding for the unit mustalso comply with the current edition of CSA ,Canadian Electrical unit heaters are CSA certified for clearances tocombustible material listed on the rating plate and table clearance must be provided around theappliance and around air openings into the combustionchamber.

10 Provision must be made for : Fire protection clearances may be exceeded toprovide additional space for service and 3 UNIT CLEARANCES TO COMBUSTIBLE MATERIALSTopSidesBottomRearFlueinmminmmi nmminmminmm6152615200184576152 GARAGE / WAREHOUSE INSTALLATIONS 1 In a storage area, clearance from the heater tocombustible materials must be such that thecombustible material must not attain a temperatureabove 160 F (71 C) during continuous operation ofthe materials that are affected by ex-posure to temperatures less than 160 F (plas-tics, plastic wrap, styrofoam, cardboard, etc.)