FieldBench
Wiring

ComfortBridge inverter AC

1/2 data — or 24V Y

1/2 data — or 24V Y

GXV9S / AXV9S / GSXV class. Outdoor drive, no reversing valve. Communicating indoor on 1/2. 24V indoor gets Y and C only.

Written circuit description only — FieldBench does not redraw maker schematics. Example: R to W closes on a heat call; verify 24V at W1 before you change the IFC.

Open manufacturer PDF

ComfortBridge indoor

GMVC / AMVC / AVPTC requesting capacity on 1/2.

ComfortBridge pair

Indoor 1 and 2 to outdoor 1 and 2. Polarity matters. This is not 24V Y.

  • 1DataData
  • 2DataData

Outdoor line — inverter drive

208/230 into the drive. No contactor slam. DC bus can stay live after the disconnect.

  • L1Line to the driveLine
  • L2Line to the driveLine
  • GNDEquipment groundLine

Landing

  • DataIndoor 1/2outdoor 1/2

    Data. Capacity is serial.

  • LineL1 / L2drive

    208/230. No contactor.

24V indoor

GR9T96 / AR9T96 / any conventional Y.

Wall thermostat

Conventional 24V. One cool stage.

  • R24V hot from indoor transformer24V
  • C24V common24V
  • YCool call — one stage24V
  • GIndoor fan24V
  • WHeat. Stays at the indoor.24V

Indoor IFC / AHU

Y in from the stat. Y out to the outdoor contactor. Same transformer.

  • RTransformer hot — feeds the stat24V
  • CTransformer common — must reach the outdoor24V
  • YStat Y in24V
  • YoutTo outdoor contactor coil24V
  • GBlower / cool tap24V
  • WHeat only24V

Outdoor — contactor coil

Y is a call to the drive, not a contactor coil you listen for.

  • YContactor coil. ~24 VAC to C under a call.24V
  • CContactor coil common24V

Outdoor line — inverter drive

208/230 into the drive. No contactor slam. DC bus can stay live after the disconnect.

  • L1Line to the driveLine
  • L2Line to the driveLine
  • GNDEquipment groundLine

Landing

  • 24VStat Yindoor Youtdoor Y

    ~24 VAC call. Drive ramps. No slam.

  • 24VC throughout

    Common

Prove it

  • Drive LEDs / display. There is no contactor to chase.
  • Charge is weigh-in + line-set.

Do not

  • Do not throw a dual run cap.
  • Do not ohm a defrost sensor. That is GSZC / ASZC.

Same 1/2 pair as GSXC18. The outdoor is a drive, not a two-stage scroll board.

Plates on this landing