FieldBench
Trane codes

Trane

Draft / PS

Lockout

Metal-vent pressure / draft (door decimals)

Inducer running, metal-vent prove failed — or the switch is already made. If the door prints S9-looking E-decimals, confirm the line here. Physics are chimney/inducer, not collector drown.

Walk Draft / PS in Diagnose

4 plates — walk the one on the cabinet

First check

1 Prove inducer and the live code

Do not pull power — that clears the Trane S8B1 active code. Write Draft / PS. Is the inducer spinning on this call? Silent inducer is not a pressure switch. This is Category I metal vent. There is no 96% collector or PVC trap to prime.

Expect: 120 VAC at the inducer on a heat call. Wheel turning.

If fail: 120 VAC missing → IFC / door switch / incoming power. Voltage + dead motor → inducer.

If pass: Inducer running + this code → trap, hose, switch, vent (step 2).

The rest of the walkthrough is Diagnose.

On the plates

  • Liner, cap, common-vent tables, chimney termination. Spillage at the inducer inlet is a fail.
  • Inducer wheel intact and spinning. Hose to the inducer housing — flue condensate in a long metal run can still fill a hose, but it is not a 96% collector.
  • Do not cut or dump a PVC trap. There isn’t one.
  • S8X2: low vs high draft path if two switches exist. S8X1: one switch.
  • This is Category I metal vent. There is no 96% collector or PVC trap to prime.
  • Cap, liner, common-vent tables, inducer wheel, hose on the inducer housing.

Plates that use Draft / PS