FieldBench
York codes

York

PS

Protect

Pressure switch

Inducer ran (or should have) and the draft switch did not make.

Walk PS in Diagnose

Sign in for the next measurement

First check

1 Prove inducer and the live code

Do not pull power — that clears the York ZF active code. Write PS. Is the inducer spinning on this call? Silent inducer is not a pressure switch. Inducer spinning. Wheel packed with rust / nest.

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

  • Inducer spinning. Wheel packed with rust / nest.
  • Hose on the inducer tap, not cracked, not full of water. Roof units collect condensate in the hose.
  • Flue / heat-exchanger restriction. Birds and insulation in the collector are a rooftop classic.
  • Switch ohms with inducer forced. Do not leave it jumped.

Plates that use PS

Same number, other makers

PS on York is not the same code on these plates.