What It Means
- CONFLICTING TSTAT INPUT
Lennox Unit controller
Lennox Unit controller Error Code 86
Unit controller
Causes & actions from Lennox
How it shows
- M4 alarm code: 86
Check thermostat inputs for simultaneous heat and cooling wiring. Once condition is corrected, unit controller will resume operation after error time off day has expired.
Applicable models & manual sources
- MODEL L - M4 UNIT CONTROLLER
CONFLICTING TSTAT INPUT
MODEL L - M4 UNIT CONTROLLER, M4 Unit Controller
Disclaimer: This information is for general reference. Code wording and instructions vary by model. Always follow the service manual for your exact unit.
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