Error Code 29

EC29 or Error Code 29

An error code 29 indicates a problem draining the condensate¹ from the unit. This code only applies to our high efficiency condensing models. Just like if you leave a cold can of soda out in a warm area and condensate forms on the outside, a condensing unit creates condensate when cold water passes through the secondary heat exchanger and is heated. Due to the use of the hot exhaust to pre-heat the water before it enters the primary heat exchanger, the condensate is acidic and generally needs to be run into a neutralizer² before going into a floor drain or other drainage system if it has metal pipes. Local code will stipulate whether or not you need to neutralize the condensate.

The condensate draining from the unit does not have any pressure behind it and relies on gravity to allow if to flow out of the unit, through the piping and into it’s final drain area. The condensate drain line from the unit must be no smaller than 1/2″ inner diameter and must be a plastic material. Additionally the drain line should be as short and direct as possible and always sloped towards the end drain point.

There should be no additional traps in the condensate drain line as the units have a trap internally. If the condensate is run to the outside in areas that freeze, the line could become frozen causing a backup and a 29 code. Either route the line to an area that will not freeze or take preventative measures to prevent it from freezing.

For further technical assistance call 866-766-7489 or use our Contractor Locator to find a local service representative.

Article Definitions

condensate¹
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.

neutralizer_²
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.