Carrier FA4ANF Service Manual

weights (clips) on blower wheel vanes. Do not drop or bendwheel as balance will be affected.To reassemble unit, proceed as follows:1. Place motor with mount attached on flat, horizontal surfacewith shaft up.2. Set inlet ring on top of motor mount grommets. Center inletring flush on all 3 grommets.3. Slide blower wheel onto motor shaft with setscrew upwardand aligned with shaft flat portion. Vertically position wheelalong shaft to position marked during disassembly.NOTE: If previous shaft was not marked or if replacing previousmotor, set blower wheel position by sliding blower wheel alongmotor shaft to 1-1/8 in. above rubber grommets. (See Fig. 34.)4. Hold blower wheel in place and carefully tighten setscrew.5. Position motor and blower wheel assembly to blower housingas originally oriented.6. Secure motor mount to blower housing using bolts previouslyremoved.7. Attach green wire to blower housing with screw.8. Connect electrical and capacitor leads to original terminals.9. Replace blower access door and tighten all 4 screws.10. Reinsert disconnect pullout only after blower access door issecured. Test blower for proper operation.FD3A SERVICE AND TROUBLESHOOTINGBefore installation or servicing system, always turn off mainpower to system. There may be more than 1 disconnectswitch. Turn off accessory heater power if applicable. Elec-trical shock can cause personal injury or death.Step 1—Fan MotorThe motor is 2-speed direct drive. High-speed lead is black,low-speed lead is red, and common lead is yellow.NOTE: Unused fan speed leads must be tapped off to preventdirect short to cabinet surface.The motor is turned on through 2 different routes. The first occurswhen thermostat calls for the fan in cooling, heat pump, orfan-only mode. A 24-vac signal is sent to relay, causing relay toclose its normally-open contacts, turning fan on. The secondoccurs when there is a call for electric heat. A 24-vac signal is sentto heater sequencer, causing it to close, directing 230v through thenormally-closed contact of fan relay, turning fan on. The fanremains on until sequencer opens. Refer to FD3A typical wiringdiagram. (See Fig. 35.)Step 2—Electric Heater ServiceService can be completed with heater in place. Shut off powerbefore servicing.LIMIT SWITCHRefer to Electric Heater Function and Troubleshooting section ofthis manual.SEQUENCERRefer to Electric Heater Function and Troubleshooting section ofthis manual.TRANSFORMERA 60-VA transformer supplies 24-v power for control circuit.Check for 208/230-v on primary side of transformer. If present,check for 24-v on secondary side. Replace transformer if faulty.NOTE: Transformer is fused. Do not short circuit.FAN RELAYRelay coil is 24 volts. Check for proper control voltage. Replacerelay if faulty.HEATER REMOVALDisconnect wiring, remove 2 sheet metal screws, and pull heaterout through open hinged access panel. When replacing heater,ensure orientation of heater element is same as when removed.Step 3—Cleaning or Replacing RefrigerantFlow-Control Device1. Pump down outdoor unit. Close service valves at outdoor unit.Fig. 34—FF1A/FF1B/FF1C Motor, Inlet Ring, and Blower Wheel AssemblyA86006GROMMETBLOWERWHEELINLETRINGMOTOR1 1⁄8″43