FieldBench
Trane codes

Trane

PS open / closed

Lockout

Single pressure switch (door decimals)

One switch, one hose, 96% collector/trap. Open = will not prove. Closed/shorted = already made with inducer off. Use the decimals printed on THIS door — do not import S9V2 E3.1/E3.3 or a second-stage pair.

Walk PS open / closed in Diagnose

4 plates — walk the one on the cabinet

First check

1 Unplug the switch with the inducer off

On Trane S9B1 this code is the switch made when the inducer is not running. Unplug that switch only. Trap and collector first. A drowned 96% will not make the single prove.

Expect: Code changes when the harness is open.

If fail: Wrong switch, or the IFC input is shorted.

If pass: Switch/hose path. Go to step 2.

The rest of the walkthrough is Diagnose.

On the plates

  • Two hoses, two switches. A tee is a miswire.
  • Trap, collector, PVC, wind, ice — 96% will not make pressure with a full trap.
  • Does the inducer actually change speed on W2?
  • Unplug the suspect switch: code change = switch/hose; no change = IFC input.
  • Trap and collector first. A drowned 96% will not make the single prove.
  • Inducer spinning? Hose on the only port, not left over from an S9X2 two-hose install.
  • Unplug the switch: code change = switch/hose; no change = IFC input.
  • Vent/intake ice, wind, slope back to the collector.

Plates that use PS open / closed