Carrier 59CU5A Installation, Start-up, Operating And Service And Maintenance Instructions

59CU5A: Installation, Start-up, Operating and Service and Maintenance InstructionsManufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.273. Secure power cord to J-Box bracket with a strain relief bushing or aconnector approved for the type of cord used.4. Pull furnace power wires through 1/2-in. (12 mm) diameter hole inJ-Box. If necessary, loosen power wires from strain—relief wire-tieon furnace wiring harness.5. Connect field ground wire and factory ground wire to green groundscrew on J-Box mounting bracket, see Fig. 38.6. Connect power cord power and neutral leads to furnace powerleads, see Fig. 40.7. Attach furnace J-Box cover to mounting bracket with screwssupplied in loose parts bag. Do not pinch wires between cover andbracket, see Fig. 38.BX Cable Installation in Furnace J-Box1. Install J-Box mounting bracket to inside of furnace casing, seeFig. 38.2. Route BX connector through 7/8-in. (22 mm) diameter hole incasing and J-Box bracket.3. Secure BX cable to J-Box bracket with connectors approved for thetype of cable used.4. Connect field ground wire and factory ground wire to green groundscrew on J-Box mounting bracket, see Fig. 38.5. Connect field power and neutral leads to furnace power leads, seeFig. 40.6. Attach furnace J-Box cover to mounting bracket with screwssupplied in loose parts bag. Do not pinch wires between cover andbracket.24-V WiringMake field 24-v connections at the 24-v terminal strip, see Fig. 42.Connect terminal Y/Y2, see Fig. 76, for proper cooling operation. Useonly AWG No. 18, color-coded, copper thermostat wire.NOTE: Use AWG No. 18 color-coded copper thermostat wire forlengths up to 100 ft. (31 M). For wire lengths over 100 ft., use AWG No.16 wire.The 24-v circuit contains an automotive-type, 3-amp. fuse located on thecontrol. Any direct shorts during installation, service, or maintenancecould cause this fuse to blow. If fuse replacement is required, use ONLYa 3-amp. fuse of identical size, see Fig. 42.ThermostatsA single stage heating and cooling thermostat can be used with thefurnace. The furnace control board CPU will control the outdoor unitstaging. A 2-stage thermostat can also be used to control the two-stagecooling. For 2-stage thermostat control of a 2-stage outdoor unit, removethe ACRDJ jumper from the furnace control board. Refer to typicalthermostat wiring diagrams and the Sequence of Operation section foradditional details. Consult the thermostat installation instructions forspecific information about configuring the thermostat. , see Fig. 42 andThermostat wiring)ACCESSORIES1. Electronic Air Cleaner (EAC)Connect an accessory Electronic Air Cleaner (if used) using 1/4-in.female quick connect terminals to the two male 1/4-in.quick-connect terminals on the control board marked EAC-1 andEAC-2. The terminals are rated for 115VAC, 1.0 amps maximumand are energized during blower motor operation.2. Humidifier (HUM)The HUM terminal is a 24 VAC output, energized when the bloweris operating during a call for heat. Connect an accessory 24 VAC,0.5 amp. maximum humidifier (if used) to the 1/4-in. malequick-connect HUM terminal and COM-24V screw terminal on thecontrol board thermostat strip.NOTE: : If the humidifier has its own 24 VAC power supply, anisolation relay may be required. Connect the 24 VAC coil of theisolation relay to the HUM and COM/24V screw terminal on thecontrol board thermostat strip, see Fig. 42.3. Communication Connector (communication connection) Thisconnection is used when the furnace is controlled by an optionalcommunicating User Interface instead of a standard thermostat. Thecommunication plug is supplied with the User Interface. Refer tothe instructions supplied with the User Interface for completedetails, see Fig. 42.4. Outside Air Thermistor (OAT)The OAT connection is used in conjunction with communicatingUser Interface. It is not required when the furnace is controlled by astandard type thermostat. Refer to the instructions supplied with theUser Interface for complete details.Alternate Power SuppliesThis furnace is designed to operate on utility generated power which hasa smooth sinusoidal waveform. If the furnace is to be operated on agenerator or other alternate power supply, the alternate power supplymust produce a smooth sinusoidal waveform for compatibility with thefurnace electronics. The alternate power supply must generate the samevoltage, phase, and frequency (Hz) (Table 13) or the furnace rating plate.Power from an alternate power supply that is non-sinusoidal maydamage the furnace electronics or cause erratic operation.Contact the alternate power supply manufacturer for specifications anddetails.WARNING!FIRE, EXPLOSION, ELECTRICAL SHOCK, ANDCARBON MONOXIDE POISONING HAZARDFailure to follow this warning could result in dangerous operation,personal injury, death, or property damage.Do not drill into blower shelf of furnace to route control wiring. Routeany control or accessory wiring to the blower compartment throughexternal knockouts on the casing.