Error Code Continuous ON

Trane TUD1B080A9H31B Error Code Continuous ON: Replace IFC

TL;DR
The LED stays on continuously without blinking, indicating the Integrated Furnace Control (IFC) board has failed and must be replaced.
Disclaimer
This article is for informational purposes only and does not guarantee the accuracy or completeness of the information provided. Always turn off power and gas supply before attempting any repairs. If you smell gas, leave immediately and call your gas company. Consult a licensed HVAC technician for diagnosis and repair. Any actions taken based on this information are at your own risk.

What Does Code Continuous ON Mean?

The LED stays on continuously without blinking, indicating the Integrated Furnace Control (IFC) board has failed and must be replaced.

When to Call a Professional

Contact a licensed HVAC technician if:

Sources

  1. ManualsLib - Trane AUD1A040A9H21B Installer's Manual (18-CD21D1-12), which explicitly covers *UD1B080A9H31B where * = A or T. (page 24). Also available as Trane TUD1B080A9H31B Installer's Manual: