FieldBench
Lennox codes

Lennox

Drain

Protect

Condensate / float

Float switch or tripped condensate opened 24V.

Walk Drain in Diagnose

2 plates — walk the one on the cabinet

First check

1 Float and the pan

On Lennox LGH a drain / float code is water until proven otherwise. Pan full? Float stuck? Secondary drain piped? Roof drain pan, trap, and the overflow to the roof — not a furnace collector.

Expect: Pan dry after you clear it. Float moves freely.

The rest of the walkthrough is Diagnose.

On the plates

  • Roof drain pan, trap, and the overflow to the roof — not a furnace collector.
  • A clogged pan on a curb soaks the deck. Fix the drain before the board.

Plates that use Drain

Same number, other makers

Drain on Lennox is not the same code on these plates.