FieldBench
Carrier codes

Carrier

COMM

Lockout

ABCD / outdoor drop

Drive or bus. Wall control loses the outdoor.

Walk COMM in Diagnose

6 plates — walk the one on the cabinet

On the plates

  • R to C at the control. 0 VAC = missing C, not a dead furnace.
  • A/B polarity. D is not W.
  • One SYSTX-class control on the bus. A 59TP6 hanging this stat will never talk.
  • R to C. A/B polarity. D is not W.
  • One control on the bus.
  • 59TP6 + this stat is the wrong bus — load 59TP6, not this plate.
  • ABCD landing and polarity, outdoor board power, inverter comms harness.
  • C still required at the wall control.

Plates that use COMM

Same number, other makers

COMM on Carrier is not the same code on these plates.