Lennox Unit controller

Lennox Unit controller Error Code 17

Unit controller

What It Means

  • HIGH PRESSURE STRIKE 3 - COMPRESSOR 3

Causes & actions from Lennox

How it shows
  • M4 alarm code: 17

• Compressor lockout. Check charge, fans and coil. Use CORE Service application RTU > SERVICE menu to clear lockouts. • User will be able to clear high pressure switch compressor lockout and alarm through the user interface. High pressure switch compressor lockout and alarm will be cleared after the CORE Unit Controller reset. • High pressure switch compressor lockout and alarm is cleared on removal of cooling demand. Default is 3 occurrences and can be set between 1 and 7 occurrences.

Applicable models & manual sources
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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