Lennox Split & Multi-Split

Lennox Error Code E426

Split & Multi-Split: Air conditioner (outdoor)

What It Means

  • Excessive inverter alarms

Causes & actions from Lennox

How it shows
  • Outdoor control 7-segment display: E426

After ten faults within one hour, control is locked out, indicating poor system operation. Review history of alarms to resolve system setup. Check condenser fan motor, TXV, indoor unit blower motor, over-charge, undercharge, or clogged refrigerant filter. To clear, disconnect power to the indoor unit (24VAC power source to the outdoor control) which will power off the outdoor control and will open the outdoor unit contactor, which interrupts power to the inverter and then re-apply power. Inverter alarms 12 to 14 and 53 do not count toward this lock out condition.

Other manual wording

EL18XCV, EL18XCV-024, EL18XCV-036, EL18XCV-048, EL18XCV-060, EL18XPV, EL18XPV-024, EL18XPV-036, EL18XPV-048, EL18XPV-060, EL22KCV,…

After ten faults within one hour, control will lock out. Indicates poor system operation. Review history of alarms to resolve system setup. Check condenser fan motor, TXV, indoor unit blower motor, stuck reversing valve, over- charge, undercharge, and clogged refrigerant filter. To clear, disconnect power to the indoor unit (24VAC power source to the outdoor control) which will power off the outdoor control and will open the outdoor unit contactor, which interrupts power to the inverter and then re-apply power. Inverter alarms 12 to 14 and 53 do not count towards this lock out condition.

Applicable models & manual sources
  • EL18XCV

    Excessive inverter alarms

    EL18XCV, EL18XCV-024, EL18XCV-036, EL18XCV-048, EL18XCV-060

    EL18XCV manual, page 37

  • EL18XPV

    Excessive inverter alarms

    EL18XPV, EL18XPV-024, EL18XPV-036, EL18XPV-048, EL18XPV-060

    EL18XPV manual, page 38

  • EL22KCV

    Excessive inverter alarms

    EL22KCV, EL22KCV-024, EL22KCV-036, EL22KCV-048, EL22KCV-060

    EL22KCV manual, page 41

  • SL25KCV

    Excessive inverter alarms

    SL25KCV, SL25KCV-024, SL25KCV-036, SL25KCV-048, SL25KCV-060

    SL25KCV manual, page 37

  • SL28XCV

    Excessive inverter alarms

    SL28XCV, SL28XCV-024, SL28XCV-036, SL28XCV-048, SL28XCV-060

    SL28XCV manual, page 31

  • EL18XCV

    Excessive inverter alarms

    EL18XCV, EL18XCV-024, EL18XCV-036, EL18XCV-048, EL18XCV-060

    EL18XCV manual, page 76

  • EL18XPV

    Excessive inverter alarms

    EL18XPV, EL18XPV-024, EL18XPV-036, EL18XPV-048, EL18XPV-060

    EL18XPV manual, page 79

  • EL22KCV

    Excessive inverter alarms

    EL22KCV, EL22KCV-024, EL22KCV-036, EL22KCV-048, EL22KCV-060

    EL22KCV manual, page 76

  • SL25KCV

    Excessive inverter alarms

    SL25KCV, SL25KCV-024, SL25KCV-036, SL25KCV-048, SL25KCV-060

    SL25KCV manual, page 71

  • SL28XCV

    Excessive inverter alarms

    SL28XCV, SL28XCV-024, SL28XCV-036, SL28XCV-048, SL28XCV-060

    SL28XCV manual, page 65

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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