FieldBench
Trane codes

Trane

No mod

Protect

Damper not modulating

Damper is two-position (0 or 100) instead of tracking 2–10 V. Title 24 FDD class.

Walk No mod in Diagnose

2 plates — walk the one on the cabinet

First check

1 Damper position vs command

On Trane YHC look at the economizer before the compressor. Commanded open? Blade actually open? Linkage off the shaft is a rooftop weekly. 2–10 V at the actuator while OA is in the window. 0 V or 24 V only = module output or a two-position actuator installed by mistake.

Expect: Blade matches the module command. Stuck open = overventilation. Stuck closed = no free cooling.

The rest of the walkthrough is Diagnose.

On the plates

  • 2–10 V at the actuator while OA is in the window. 0 V or 24 V only = module output or a two-position actuator installed by mistake.
  • JADE set for 2-position vs modulating. Direct-coupled actuator vs a 24 V floating that someone landed on analog.
  • Stuck at 50% is a failed actuator, not ‘modulating.’

Plates that use No mod

Same number, other makers

No mod on Trane is not the same code on these plates.