Fault Code Lookup

HVAC Sales Master
3 flashes
Inducer or pressure switch error
This code typically points to
  • Blocked vent or intake
  • Weak inducer or inducer failure
  • Split or blocked pressure tubing
  • Bad pressure switch

Next checks to confirm
  1. Verify inducer operation
  2. Inspect venting and pressure tubing
  3. Verify actual negative pressure during operation

Escalation
If draft proves good but switch never closes or behaves erratically, switch or board input becomes more likely.
Reset behavior
Stored in memory; auto-erased after 14 days.
Urgent
Fix now
Cross-generation conflict
Source
Emerson 50V64-743 diagnostic features