Error Code No R-to-O Output for Heat Pump
Lennox SLP98UHV Error Code No R-to-O Output for Heat Pump: No R-to-O Output for Heat Pump
TL;DR
No 24 volts detected between R and O terminals with a non-communicating outdoor unit. The heat pump reversing valve relay configuration link needs to be cut. 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 No R-to-O Output for Heat Pump Mean?
No 24 volts detected between R and O terminals with a non-communicating outdoor unit. The heat pump reversing valve relay configuration link needs to be cut.
When to Call a Professional
Contact a licensed HVAC technician if:
- Basic troubleshooting did not resolve the error
- You smell gas at any point during the process
- You are not comfortable working around gas lines or electrical components
- The unit needs a gas valve, control board, or motor replacement