Lennox International Inc G24-200 Cooling Sequence Of Operation, For Two Condensing Units

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COOLING SEQUENCE OF OPERATION

COOLING SEQUENCE OF OPERATION

FOR TWO CONDENSING UNITS

FOR A SINGLE CONDENSING UNIT

THERMOSTAT CALLS FOR COOLING

(Y1 POWERED)

COOLING CONTACTOR OF FIRST-STAGE CONDENSING UNIT CLOSES AND SYSTEM BLOWERS START.

HAS ROOM AIR TEMPERATURE CONTINUED

TO RISE ABOVE THE THERMOSTAT"S

Y2 SET POINT?

YES

COOLING CONTACTOR OF SECOND-STAGE

CONDENSING UNIT CLOSES.

IS Y2 DEMAND SATISFIED?

YES

SECOND-STAGE COOLING

UNIT CONTACTOR OPENS

IS Y1 DEMAND SATISFIED?

YES

FIRST-STAGE COOLING UNIT

CONTACTOR OPENS AND B3

SYSTEM BLOWERS OFF.

THERMOSTAT CALLS FOR COOLING

(Y1 POWERED)

COOLING CONTACTOR OF CONDENSING UNIT

CLOSES AND SYSTEM BLOWERS START.

IS Y1 DEMAND SATISFIED?

YES

COOLING UNIT CONTACTOR

OPENS AND B3 SYSTEM

BLOWERS OFF.

MANUAL FAN OPERATION

MANUAL FAN SELECTION MADE AT THERMOSTAT.

THE BLOWERS RUN CONTINUOUSLY WITH OR WITHOUT A CALL FOR HEATING OR COOLING.

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Contents INSTALLATION INSTRUCTIONS G24-200 2P0805P504613M WHAT TO DO IF YOU SMELL GASG24−200 Unit Dimensions − inches mm PageG24−200 Filter Box Dimensions − inches mm SIDE VIEWBACK VIEW TOP VIEWPage G24−200 Parts ArrangementG24−200 HEAT SECTION AND CABINET Page G24−200 Parts Arrangement ContinuedG24−200 BLOWER SECTION Shipping and Packing List SafetyG24−200 Gas Furnace setting General Combustion, Dilution & Ventilation AirCements and glues EQUIPMENT IN CONFINED SPACE ALL AIR FROM INSIDE Setting Equipment Return Air Plenum / Filter Box InstallationBOTTOM RETURN AIR FILTER BOX INSTALLATION PageBlower Motor / Drive Installation Duct SystemVenting Venting Using a Masonry Chimney Page Page SERVING A SINGLE CATEGORY I APPLIANCE PageSERVING A SINGLE CATEGORY I APPLIANCE PageVENT CONNECTOR CAPACITY SERVING TWO OR MORE CATEGORY I APPLIANCESSERVING TWO OR MORE CATEGORY I APPLIANCES COMMON VENT CAPACITYPage CARBON MONOXIDE POISONING HAZARD Page FOR INSTALLATIONS IN THE USA AND CANADAVENT TERMINATION CLEARANCES Horizontal Venting Gas Piping FIRE OR EXPLOSION HAZARD Electrical G24−200 FIELD WIRING DIAGRAM 120V SINGLE PH 60HZ Alternate make-upbox right side Alternate make-upG24-200FIELD WIRING DIAGRAM G24−200 FIELD WIRING DIAGRAM G UNITS − 460V 3PH 60HZJ UNITS − 575V 3PH 60HZ Alternate make-upFIGURE Page WIRING SCHEMATIC DIAGRAM FOR G24−200 P UNITS − 208/230V 1PH 60 HZY UNITS − 208/230V 3PH 60HZ G UNITS − 460V 3PH 60HZUnit Start−Up Heating Sequence of Operation High Altitude Information Gas Pressure AdjustmentOther Unit Adjustments and Operation Temperature Rise Setting blower CFM Page TABLE ACCESSORY AIR RESISTANCETABLE DRIVE KIT SPECIFICATIONS Repair Parts List G24−200 Start−up and Performance Check ListTroubleshooting NORMAL HEATING MODEABNORMAL HEATING MODE Page3 − OFF NO POWER OR DETECTED FAULT NORMAL HEATING MODEABNORMAL HEATING MODE LED CODESPOWER ON THERMOSTAT CALLS FOR HEAT W1 ENERGIZED IS THE S10 S99 HIGH LIMIT CLOSED? YES COOLING SEQUENCE OF OPERATION FOR TWO CONDENSING UNITSFOR A SINGLE CONDENSING UNIT MANUAL FAN OPERATION