Lennox International Inc SL280UH070V36A Call for SECOND−STAGE Heat, Call for Heat Satisfied

Page 69

Troubleshooting: Heating Sequence of Operation (Continued)

CALL FOR SECOND−STAGE HEAT

2

 

CALL FOR 2ND STAGE HEAT

1

 

 

 

 

(HIGH FIRE)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

2 STAGE THERMOSTAT

 

 

 

 

 

 

 

 

 

RECOGNITION DELAY

 

 

(30 SECONDS)

ONLY FOR 1ST EXPIRED?

REQUEST FOR

 

 

 

2ND STAGE HEAT

 

YES

 

 

 

 

 

 

 

SINGLE STAGE THERMOSTAT 2

2ND STAGE ON DELAY EXPIRED?

YES

INDUCER SWITCHED

TO HIGH SPEED

HIGH

 

 

 

 

 

 

 

PRESSURE SWITCH

 

 

 

 

INDUCER SWITCHED

 

 

 

NO

 

 

CLOSED WITHIN 10

 

 

 

TO LOW SPEED

 

 

 

 

 

 

SECONDS?

 

 

 

 

 

 

 

YES

2ND STAGE GAS VALVE

ENERGIZED

INDOOR BLOWER ENERGIZED

ON HIGH HEAT SPEED

3

CALL FOR HEAT SATISFIED

5 MINUTE DELAY

3

(ERROR CODE FLASHES)

1SYSTEM WILL ALWAYS LIGHT ON LOW FIIRE, EVEN IF 2ND STAGE HEAT IS IN PLACE.

2WHEN USED WITH A SINGLE STAGE THERMOSTAT, SET SW1 TO THE ON POSITION IN DIP SWITCH S4.

3IF THE HIGH FIRE PRESSURE SWITCH DOES NOT CLOSE WITHIN 5 ATTEMPTS, THE SYSTEM WILL OPERATE AT LOW FIRE FOR THE REMAINDER OF THE CALL FOR HEAT REQUEST.

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Contents Table of Contents Installation Instructions SL280UHVReturn air from both sides Unit Dimensions − inches mmSide Return Air Opening Either SideAccess Panel Blower Assembly Parts ArrangementSight Glass Safety Information SL280UHV Gas FurnaceShipping and Packing List General Use of Furnace as Construction HeaterAir Handler Unit EvaporatorCombustion, Dilution & Ventilation Air Space ALL AIR from Inside Equipment in ConfinedEquipment in Confined Space ALL AIR from Outside Equipment in Confined SpaceEquipment Confined Space ALL AIR from Outside Setting Equipment BottomBlower Motor Rigid LEG Furnace Front 20 X 25 XIndoor AIR Return AIR BaseRight Horizontal Application Installation Clearances Top LeftEnd Bottom Typical Horizontal ApplicationDuct System FiltersUpflow Position VentingTop Vent Discharge Left Side Vent DischargeHorizontal Left Position Horizontal Right PositionSide Vent Discharge Disconnected Vent Common Venting Using Metal−Lined Masonry ChimneySticker Vent PipeThrough an unused masonry chimney flue is not considered Vent Connector102 127 −1/2 152 178 10−1/2 MIN MAX Feet FAN + FAN FAN + NAT 130 Carbon Monoxide Poisoning Hazard − In some localities, codes may require the installation Ers or straps. Install a drip leg in vertical pipe runs toGas Piping Every 8 to 10 feet 2.44 to 3.01 m with suitable hangHorizontal Application Left−Side Air DischargeRight−Side Air Discharge Electrical Interior MAKE−UP BOX InstallationElectrostatic Discharge ESD BOXCommunicating Non−CommunicatingIcomfortt Integrated Control Outdoor Unit Icomfort Touch Communicating System Wiring NON−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 Integrated Control RS−BUS Link TB82, future use+ = Data High Connection − = Data LOW Connection −10% approx OFF On−Board Links 985 1045940 880SL280UH090V36B Blower Performance less filter 1220 12801155 10951235 12951170 11101230 13601165 11001225 12901160 1380+18% 1605 SL280UH110V60C Blower Performance less filter +18% 1785 SL280UH135V60D Blower Performance less filter Operating Sequence Thermostat energizes Y2 CompressorUnit Start−Up For Your Safety Read Before LightingWhite Rodgers GAS Valve Honeywell GAS ValveGAS Meter Clocking Chart Gas Pressure AdjustmentProper Combustion DialHigh Altitude Heating Sequence of Operation Other Unit AdjustmentsHeating Operation with TWO−STAGE Thermostat Heating Operation with Single Stage ThermostatSEC Electrical SHOCK, Fire Or Explosion Hazard Service13− To clean the combustion air inducer visually inspect SL280UHV BURNER, Combustion AIR Inducer Assembly11− Back wash using steam. Begin from the burner opening 17− Reinstall burner box, manifold assembly and burner boxSL280UHV NOX Inserts Repair Parts List Planned ServiceIntegrated Control Diagnostic Codes Integrated Control Diagnostic ModesFurnace / air handler. Clears after fault recovered Normal operation 5 seconds after fault recoveredPower at the thermostat. Alert stops all services Equipment is unable to communicate. IndicatesMissioning and Execute ’Set Factory Default mode’ Reconfigure the system. Replace control if heatingControl will still operate on default parameter set Ate feature will be set as ’installed’ and that couldSumes normal operation after fault is cleared Low pressure switch failed openFault is cleared Tion after fault is clearedOut. Clears when flame has been proven stable Open or not within specifications −hour soft lockSoft lockout or reset To flame failureIs not running. Check power to outdoor unit. Clears Pair/add duct. Cleared after the current service deError after current is sensed in both RUN Vice is removed, or after power resetSor run cycle, or after power reset Finished Program Unit Capacity/Size ModeCall for FIRST−STAGE Heat Troubleshooting Heating Sequence of OperationCall for Heat Satisfied Call for SECOND−STAGE Heat2ND Stage Heat Call for Heat Satisfied FIRST−STAGE Heat SECOND−STAGE HeatCall for Cooling Troubleshooting Cooling Sequence of OperationCall for FAN Troubleshooting Continuous Fan Sequence of Operation
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