FieldBench
Rheem codes

Rheem

45 / 57

Lockout

Draft at a firing rate

Modulating inducer / pressure did not prove at the commanded %. Not a simple two-switch tee like R96TA or the VA 45/46 split.

Walk 45 / 57 in Diagnose

2 plates — walk the one on the cabinet

First check

1 Prove inducer and the live code

Do not pull power — that clears the Rheem R98MV active code. Write 45 / 57. Is the inducer spinning on this call? Silent inducer is not a pressure switch. Vent, trap, collector, inducer throughout the rate, pressure hose / transducer path.

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

  • Vent, trap, collector, inducer throughout the rate, pressure hose / transducer path.
  • Do not replace ‘the low PS’ off an R96TA card.
  • Watch whether the fault appears only at higher % — that is vent capacity, not a dead switch.

Plates that use 45 / 57