Carrier 48EZ(N)-A Installation Instructions Manual

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Contents

12Step 10 — Install Electrical ConnectionsELECTRICAL SHOCK HAZARDFailure to follow this warning could result in personal injuryor death.The unit cabinet must have an uninterrupted, unbrokenelectrical ground. This ground may consist of an electricalwire connected to the unit ground screw in the controlcompartment, or conduit approved for electrical ground wheninstalled in accordance with NEC, NFPA 70 National FireProtection Association (latest edition) (in Canada, CanadianElectrical Code CSA C22.1) and local electrical codes.! WARNINGUNIT COMPONENT DAMAGE HAZARDFailure to follow this caution may result in damage to the unitbeing installed.1. Make all electrical connections in accordance with NECNFPA 70 (latest edition) and local electrical codesgoverning such wiring. In Canada, all electricalconnections must be in accordance with CSA standardC22.1 Canadian Electrical Code Part 1 and applicablelocal codes. Refer to unit wiring diagram.2. Use only copper conductor for connections betweenfield--supplied electrical disconnect switch and unit. DONOT USE ALUMINUM WIRE.3. Be sure that high--voltage power to unit is withinoperating voltage range indicated on unit rating plate. On3--phase units, ensure phases are balanced within 2percent. Consult local power company for correction ofimproper voltage and/or phase imbalance.4. Insulate low--voltage wires for highest voltage containedwithin conduit when low--voltage control wires are insame conduit as high--voltage wires.5. Do not damage internal components when drillingthrough any panel to mount electrical hardware, conduit,etc.! CAUTIONHigh--Voltage ConnectionsWhen routing power leads into unit, use only copper wire betweendisconnect and unit. The high voltage leads should be in a conduituntil they enter the duct panel; conduit termination at the ductpanel must be watertight.The unit must have a separate electrical service with afield--supplied, waterproof disconnect switch mounted at, or withinsight from, the unit. Refer to the unit rating plate, NEC and localcodes for maximum fuse/circuit breaker size and minimum circuitamps (ampacity) for wire sizing.The field--supplied disconnect switch box may be mounted on theunit over the high--voltage inlet hole when the standard power andlow--voltage entry points are used (See Fig. 2 and 3 for acceptablelocation).NOTE: Field supplied disconnect switch box should bepositioned so that it does not cover up any of the unit gascombustion supply air louvers.See unit wiring label (Fig. 14 and 15) and Fig. 9 for referencewhen making high voltage connections. Proceed as follows tocomplete the high--voltage connections to the unit.Single phase units:1. Run the high--voltage (L1, L2) and ground lead into thecontrol box.2. Connect ground lead to chassis ground connection.POWERSUPPLYFIELD-SUPPLIEDFUSED DISCONNECTHIGH VOLTAGEPOWER LEADS(SEE UNIT WIRINGLABEL)EQUIP GRCONTROL BOXSPLICE BOXLOW-VOLTAGEPOWER LEADS(SEE UNITWIRING LABEL)WYGRCWHT(W1)YEL(Y)GRN(G)RED(R)BRN(C)THERMOSTAT(TYPICAL)OORN(O)GRA (Y2)BLU (DH) DH3-PhaseOnlyA09067Fig. 9 -- High and Control--Voltage Connections3. Locate the black and yellow wires connected to the line sideof the contactor.4. Connect field L1 to black wire on connection 11 of thecompressor contactor.5. Connect field wire L2 to yellow wire on connection 23 ofthe compressor contactor.Three--phase units:1. Run the high--voltage (L1, L2, L3) and ground lead into thecontrol box.2. Connect ground lead to chassis ground connection.3. Locate the black and yellow wires connected to the line sideof the contactor.4. Connect field L1 to black wire on connection 11 of thecompressor contactor.5. Connect field wire L3 to yellow wire on connection 13 ofthe compressor contactor.6. Connect field wire L2 to blue wire from compressor.Special Procedures for 208--V OperationELECTRICAL SHOCK HAZARDFailure to follow this warning could result in personal injuryor death.Make sure the power supply to the unit is switched OFF beforemaking any wiring changes. Tag the disconnect switch with asuitable warning label. With disconnect switch open, moveblack wire from transformer (3/16 in.) terminal marked 230 toterminal marked 200. This retaps transformer to primaryvoltage of 208 vac.! WARNINGELECTRICAL SHOCK AND EXPLOSION HAZARDFailure to follow this warning could result in personal injuryor death.Before making any wiring changes, make sure the gas supplyis switched off first. Then switch off the power supply to theunit and install lockout tag.! WARNING48EZ -- A