What It Means
- STRIKE 3 SUPPLY DUCT PRESSURE LIMIT
Lennox Unit controller
Lennox Unit controller Error Code 109
Unit controller
Causes & actions from Lennox
How it shows
- M4 alarm code: 109
• Check sensor and wiring. • Unit controller shall “lock out” a unit operation after the Max Static Duct Pressure Occurrences have occurred of Supply Static Pressure Sensor Error (alarm 107) and/ or High Supply Static (Duct) Pressure (alarm 108). • User shall be able to clear supply static pressure lockout and alarm via User Interface. Supply Static Pressure lockout and alarm shall be cleared after the unit controller reset. • The number of strikes is three by default. this can be changed using Parameter 43. Optional occurrence setting is 1 to 7.
Applicable models & manual sources
- MODEL L - M4 UNIT CONTROLLER
STRIKE 3 SUPPLY DUCT PRESSURE LIMIT
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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