System Diagnosis
Low-Heat Pressure Switch Did Not Close or Reopened. Low-heat pressure switch input failed to close on a call for low heat, or opened during low heat.
Troubleshooting guide for the Carrier Furnaces system fault 32.
A repeatable stop in the heating sequence at the same safety or prove step.
Weak grounding, marginal flame signal, or venting issues can produce inconsistent code behavior.
ACLogics walks you through Carrier Furnaces diagnostics step-by-step — so you confirm the cause before swapping parts.