Continuous ON
Replace IFC
This code typically points to
- Internal IFC fault
Next checks to confirm
- Verify power; if present, replace IFC
Escalation
Control-board level
Reset behavior
Persistent until board replaced.
Urgent
Fix now
Fault Code Lookup
HVAC Sales Master
Source
Trane 18-CD19D5-21 Installer's Guide, p.35-37