FieldBench
Bryant codes

Bryant

COMM OUT

Lockout

No communication with outdoor

Outdoor dropped off ABCD.

Walk COMM OUT in Diagnose

Sign in for the next measurement

First check

1 Data pair, not 24 V

On Bryant 935CA indoor/outdoor comm is a data pair (AB, S1/S2, U, ComfortBridge, ComfortLink — whatever THIS plate uses). It is not a 24 V Y. Check polarity, continuity, and that nobody landed it on R/C. Same ABCD pair at the outdoor.

Expect: Pair continuous, not shorted to chassis, polarity per the diagram.

The rest of the walkthrough is Diagnose.

On the plates

  • Same ABCD pair at the outdoor.
  • Contactor-only outdoor will never talk.
  • Setup outdoor ID vs plate.

Plates that use COMM OUT

Same number, other makers

COMM OUT on Bryant is not the same code on these plates.