Lennox Split & Multi-Split

Lennox Error Code DS2 FAST Flash, DS1 FAST Flash (Alternating)

Split & Multi-Split: Heat pump (outdoor)

What It Means

  • Coil Sensor Problem

Causes & actions from Lennox

How it shows
  • defrost control ds2 ds1 led: DS2 FAST Flash, DS1 FAST Flash (Alternating) (ds1: flashing (fast), ds2: flashing (fast))

Sensor being detected open or shorted or out of temperature range. Demand defrost control will not perform demand or time/temperature defrost operation. (System will still heat or cool.)

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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