Building Owners & Managers



Building owners and managers worldwide are continually incurring excessive property damage and degraded indoor air quality caused by the failure to successfully remove condensate (water) from air conditioning units.  These conditions are the direct result of commonly used faulty condensate drain systems. Condensate drainage is not a simple process since the pressure inside the units is generally lower (negative – a partial vacuum) than the pressure outside.  Attempts to control drainage of condensate with p-traps are costly failures. The most authoritative assessment of the condensate trap for drainage control is included in ASHRAE [American Society of Heating, Refrigerating and Air Conditioning Engineers] Standard 62-89R, paragraph 5.6.4, which reads as follows:

“Condensate traps exhibit many failure modes that can impact on indoor air quality.  Trap failures due to freeze-up, drying out, breakage, blockage, and/or improper installation can compromise the seal against air ingestion through the condensate drain line.  Traps with insufficient height between the inlet and outlet on draw-through systems can cause the drain to back-up when the fan is on, possibly causing drain pan overflow or water droplet carryover into the duct system.  The resulting moist surfaces can become sources of biological contamination. Seasonal variations, such as very dry or cold weather, may adversely affect trap operation and condensate removal.”


Consequences of Trap Failures

Despite this assessment of the condensate trap, it remains the choice of the industry as a means of drainage control. The building owners and managers suffer the consequences. Some of the many trap failure modes identified by ASHRAE are illustrated in Figure 1.  These failure modes, which occur frequently, allow condensate blowing and flooding as illustrated—causing property damage and air contamination.  Since all the air in a building passes through the air conditioning unit at a rate of several times per hour, the circulated health threatening pathogens inevitably expose occupants to degraded indoor air quality, as indicated in Figure 2.


Failed P-Trap Examples - Figure 1 Consequences of Trap Failures - Figure 2

The air conditioning units in your buildings are, undoubtedly, equipped with condensate traps. If they have been in operation at least 5 years the p-traps have probably failed several times; and have been removed, cleaned, or replaced. And the units will likely exhibit conditions like those illustrated.  If so, this deterioration can be stopped by having your service personnel install the CostGard™ Condensate Drain Seal described in the opening video.  In new construction, simply instruct designers to specify this drain seal. See: Specification and Drawings

Benefits for Building Owners and Managers

By replacing condensate traps with the CostGard™ Condensate Drain Seal, building owners and managers can realize immediate and tangible cost benefits, including reduction in:


In terms of life cycle costs, these saving are enormous since the price of the CostGard™ Condensate Drain Seal is often less than one service call to clean or replace a p-trap—not including all the other property damage and health threatening conditions that accompany trap failures.

Furthermore, it is a reality that no level of truly “sustainable green building” is possible unless draw-through air conditioning systems are equipped with the CostGard™ Condensate Drain Seal or its equivalent, and we know of no equivalent.

As you evaluate the use of the CostGard™ Condensate Drain system, you will note that building owners and managers are the only entities involved in the air conditioning industry that benefit from the cost reduction provided by reliable drain systems. Others are not enthusiastic, for good reasons. Your savings come from eliminating maintenance and service of failure-prone p-traps, which reduce the contractor’s work and business level.* And, reduced damage to air conditioning equipment, which is estimated to increase equipment life about 5 years, will have a significant impact on the manufacturer’s future production. This amounts to a reduction in production rate of about 25% percent or more. See Reference 1: New Drain Seal Replaces The P-Trap Acrobat

*The significance of this issue is indicated by the warranty contractor's often place on drain systems with p-traps. For example, contractors’ drain system warranty is commonly 60 days, while compressors and coils carry 5 to 10-year warranties. See 60 Day Warranties Acrobat

Reference 1: Trent, W. & Trent, C. (2000, November). New Drain Seal Replaces The P-Trap. Facilities Design and Management, 46-48.

Other topics on this website provide additional information about the functioning of this drain seal and are under the headings listed below: