Lennox International Inc SL280UH090V48B Service, Electrical SHOCK, Fire Or Explosion Hazard

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Service

WARNING

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 furnace.

When servicing controls, label all wires prior to dis- connecting. Take care to reconnect wires correctly. Verify proper operation after servicing.

At the beginning of each heating season, a qualified techni- cian should check the system as follows:

Blower

Check the blower wheel for debris and clean if necessary. The blower motors are prelubricated for extended bearing life. No further lubrication is needed.

WARNING

The blower access panel must be securely in place when the blower and burners are operating. Gas fumes, which could contain carbon monoxide, can be drawn into living space resulting in personal inju- ry or death.

Filters

All SL280UHV filters are installed external to the unit. Fil- ters should be inspected monthly. Clean or replace the fil- ters when necessary to ensure that the furnace operates properly. Replacement filters must be rated for high veloc- ity airflow. Table 1 lists recommended filter sizes.

Flue And Chimney

1 − Check flue pipe, chimney and all connections for tight- ness and to make sure there is no blockage.

2 − Check unit for proper draft. Electrical

1 − Check all wiring for loose connections.

2 − Check for the correct voltage at the furnace (furnace operating). Correct voltage is 120VAC + 10%.

3 − Check amp−draw on the blower motor with inner blow- er panel in place.

Unit Nameplate__________Actual__________

Cleaning the Heat Exchanger and Burners

NOTE − Use papers or protective covering in front of the fur- nace during cleaning.

1 − Turn off both electrical and gas power supplies to fur- nace.

2 − Remove flue pipe and top cap (some applications top cap can remain) from the unit.

3 − Label the wires from gas valve, rollout switches, prima- ry limit switch and make−up box then disconnect them.

4 − Remove the screws that secure the combustion air in- ducer/pressure switch assembly to the collector box. Carefully remove the combustion air inducer to avoid damaging blower gasket. If gasket is damaged, it must be replaced to prevent leakage.

5 − Remove the collector box located behind the combus- tion air inducer. Be careful with the collector box gas- ket. If the gasket is damaged, it must be replaced to prevent leakage.

6 − Disconnect gas supply piping. Remove the screw se- curing the burner box cover and remove cover. Re- move the four screws securing the burner manifold as- sembly to the vestibule panel and remove the assembly from the unit.

7 − Remove screws securing burner box and remove burner box.

8 − NOX units only − Remove screw securing NOX insert. Remove NOX insert. See figure 40.

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Contents Installation Instructions SL280UHV Table of ContentsUnit Dimensions − inches mm Return air from both sidesSide Return Air Opening Either SideSight Glass Access Panel Blower AssemblyParts Arrangement Shipping and Packing List Safety InformationSL280UHV Gas Furnace Use of Furnace as Construction Heater GeneralAir Handler Unit EvaporatorCombustion, Dilution & Ventilation Air Equipment in Confined Space ALL AIR from InsideEquipment Confined Space ALL AIR from Outside Equipment in Confined Space ALL AIR from OutsideEquipment in Confined Space Blower Motor Rigid LEG Setting EquipmentBottom 20 X 25 X Furnace FrontIndoor AIR Return AIR BaseHorizontal Application Installation Clearances Top Left RightEnd Bottom Typical Horizontal ApplicationFilters Duct SystemVenting Upflow PositionTop Vent Discharge Left Side Vent DischargeSide Vent Discharge Horizontal Left PositionHorizontal Right Position Common Venting Using Metal−Lined Masonry Chimney Disconnected VentSticker Vent PipeVent Connector Through an unused masonry chimney flue is not considered102 127 −1/2 152 178 10−1/2 MIN MAX Feet FAN + FAN FAN + NAT 130 Carbon Monoxide Poisoning Hazard Ers or straps. Install a drip leg in vertical pipe runs to − In some localities, codes may require the installationGas Piping Every 8 to 10 feet 2.44 to 3.01 m with suitable hangRight−Side Air Discharge Horizontal ApplicationLeft−Side Air Discharge Interior MAKE−UP BOX Installation ElectricalElectrostatic Discharge ESD BOXNon−Communicating CommunicatingIcomfortt Integrated Control Outdoor Unit Icomfort Touch NON−COMMUNICATING System Wiring Communicating System Wiring120V Connections ApplicationsDIP Switch Settings and On−Board Links See figure OFF Single Stage Thermostat w Dual fuel capa Bilities SL280UHV Schematic Wiring Diagram Typical SL280UHV Field Wiring Diagram + = Data High Connection − = Data LOW Connection Integrated ControlRS−BUS Link TB82, future use −10% approx OFF On−Board Links 1045 985940 880SL280UH090V36B Blower Performance less filter 1280 12201155 10951295 12351170 11101360 12301165 11001290 12251160 1380+18% 1605 SL280UH110V60C Blower Performance less filter +18% 1785 SL280UH135V60D Blower Performance less filter Operating Sequence Compressor Thermostat energizes Y2For Your Safety Read Before Lighting Unit Start−UpWhite Rodgers GAS Valve Honeywell GAS ValveGas Pressure Adjustment GAS Meter Clocking ChartProper Combustion DialHigh Altitude Other Unit Adjustments Heating Sequence of OperationSEC Heating Operation with TWO−STAGE ThermostatHeating Operation with Single Stage Thermostat Service Electrical SHOCK, Fire Or Explosion HazardSL280UHV BURNER, Combustion AIR Inducer Assembly 13− To clean the combustion air inducer visually inspect11− Back wash using steam. Begin from the burner opening 17− Reinstall burner box, manifold assembly and burner boxSL280UHV NOX Inserts Planned Service Repair Parts ListIntegrated Control Diagnostic Modes Integrated Control Diagnostic CodesNormal operation 5 seconds after fault recovered Furnace / air handler. Clears after fault recoveredPower at the thermostat. Alert stops all services Equipment is unable to communicate. IndicatesReconfigure the system. Replace control if heating Missioning and Execute ’Set Factory Default mode’Control will still operate on default parameter set Ate feature will be set as ’installed’ and that couldLow pressure switch failed open Sumes normal operation after fault is clearedFault is cleared Tion after fault is clearedOpen or not within specifications −hour soft lock Out. Clears when flame has been proven stableSoft lockout or reset To flame failurePair/add duct. Cleared after the current service de Is not running. Check power to outdoor unit. ClearsError after current is sensed in both RUN Vice is removed, or after power resetSor run cycle, or after power reset Program Unit Capacity/Size Mode FinishedTroubleshooting Heating Sequence of Operation Call for FIRST−STAGE HeatCall for SECOND−STAGE Heat Call for Heat SatisfiedCall for Heat Satisfied FIRST−STAGE Heat SECOND−STAGE Heat 2ND Stage HeatTroubleshooting Cooling Sequence of Operation Call for CoolingTroubleshooting Continuous Fan Sequence of Operation Call for FAN
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