FieldBench
York codes

York

4 red

Protect

Limit open

Airflow or overfire. Also check the board fuse.

Walk 4 red in Diagnose

5 plates — walk the one on the cabinet

First check

1 Airflow before you touch the limit

On York TM8T a limit is airflow or overfire until proven otherwise. Do not replace the limit first. Filter, blower wheel, A-coil, and the heat-speed setting for THIS motor (tap, model plug, or communicating CFM — not a sister SKU chart). TM8V: VS heat CFM menu. TM8X/Y: taps if that is the motor in the cabinet.

Expect: Rise in the rating-plate window. Static vs this cabinet’s blower chart.

The rest of the walkthrough is Diagnose.

On the plates

  • This is TM9V: heat CFM lives in the VS menu. Do not look for TM9T taps.
  • Filter, blower wheel, A-coil, return size, total external static vs the TM9V blower chart.
  • Also check the automotive fuse on the IFC — 4-red on this family includes an open board fuse.
  • Manifold low and high vs the rating plate.
  • Read the heat tap on the motor / IFC harness and match it to the TM9T tap chart and the rise range on the plate.
  • Do not open a TM9V CFM menu — there isn’t one.
  • Filter, wheel, coil, return, TES. A new media cabinet on a low heat tap will 4-red all winter.
  • Board fuse on the IFC — 4-red includes an open fuse on this JCI family.

Plates that use 4 red