Lennox Ducted Heating

Lennox Ducted Heating Error Code 5 Flashes

Ducted Heating

5 Flashes means different things on different Ducted Heating models. Enter your model number to see only your reading, or find your model below.

What It Means

  • G24M: Flame Sensed Without Demand
  • ML296UHV: Not used
  • ML180UH: Rollout switch open.
  • ML196UHE: Watchguard - burner failed to light, exceeded maximum number of retries/ recycles, 1 hour lockout
  • LF24, TUA*S(N,L)(A,S)F: Flame sensed and gas valve not energized

Causes & actions from Lennox

Flame Sensed Without Demand

Models: G24M

How it shows
  • a3 diagnostic led: 5 Flashes

Combustion Air Blower: On Gas Valve: Off Supply Air Blower: On

Applicable models & manual sources

Not used

Models: ML296UHV

How it shows
  • Integrated control red LED: 5 Flashes

This manual entry does not list further causes or actions.

Applicable models & manual sources

Rollout switch open.

Models: ML180UH

How it shows
  • integrated control single led: 5 Flashes

This manual entry does not list further causes or actions.

Applicable models & manual sources

Watchguard - burner failed to light, exceeded maximum number of retries/ recycles, 1 hour lockout

Models: ML196UHE

How it shows
  • Integrated control red LED: 5 Flashes

This manual entry does not list further causes or actions.

Applicable models & manual sources
  • ML196UHE

    Watchguard – burner failed to light, exceeded maximum number of retries/ recycles, 1 hour lockout

    ML196UHE manual, page 41

Flame sensed and gas valve not energized

Models: LF24, TUA*S(N,L)(A,S)F

Unit heater (indoor)

How it shows
  • integrated control single led: 5 Flashes

This manual entry does not list further causes or actions.

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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