Error Code 29

EC29 or Error Code 29

A 29 error code indicates a neutralizer2 drainage failure. The neutralizer2 is designed to drain condensate1 away from the heater. If the neutralizer2 and/or drain becomes blocked up, the unit will flash the 29 error code to prevent the burner from being flooded.
 Common issues related to the 29 error code include: 

  1. Blockage in the condensate1 drain line
  2. Incorrect condensate1 line piping (e.g. upward sloping of drain line, trapped drain line, incorrect size piping)
  3. For NRCP or CB models: Restriction or obstruction in the intake or exhaust venting.

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Article Definitions

Liquid water that forms when the water vapor, developed as a product of combustion, contained in exhaust gases cools enough to change into a liquid.

A device used to raise the pH of acidic condensate to a value close to 7 (neutral).

Applicable Models

  • Models: All high efficiency condensing unit that utilize PVC, CPVC or PP venting.
Updated on April 12, 2021

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