The objective of this project is to develop and demonstrate an accelerated test and measurement capability for rapidly assessing heating, ventilation, and air conditioning (HVAC) coil coatings durability and corrosion rate, provide informed corrosion mitigation strategies, and utilize the test on a set of commonly available HVAC coil coatings and novel galvanic aerospace coatings. Specifically, this project will:

1. Quantify baseline corrosion of HVAC-relevant metals and geometries under laboratory and outdoor exposures, as well as measure corrosion parameters of operational HVAC systems.
2. Assess available HVAC coil coatings, as well as a novel galvanic aerospace coating, based on durability within realistic severe environments and the coatings’ ability to reduce ice adhesion, as well as electrochemical, thermal, and mechanical properties.
3. Rank the performance of the investigated coatings, determine the economic value proposition of utilizing coatings, propose a standardized testing procedure for future testing, and provide guidance for additions to the Unified Facilities Criteria and SMS BUILDER® for severe environments.

The project team will tailor and utilize improved dynamic accelerated corrosion tests to more accurately predict HVAC coil corrosion in harsh environments. Accurate laboratory corrosion testing requires a specific understanding of the relationship between environmental variables and modes of HVAC coil corrosion failure. This requires studies of baseline corrosion events to relate environmental parameters to actual conditions at the surface of the tube, fin and frame metals, and how those conditions specifically affect corrosion and protection. Findings will be applied to identify controlling factors for different corrosion modes. The relationships between exposure parameters and the resulting corrosion damage will then be used to tailor an accelerated test method that can be standardized and will result in corrosion damage of HVAC coils more like that observed in actual field conditions than currently used standard tests. Finally, a test standard will be written and proposed to a consensus-based standard organization and additions to Unified Facilities Criteria guide specifications and Condition Index (CI) grading for SMS BUILDER® will be developed.

The chief benefit of this project will be more durable, efficient, longer lasting coils for DoD HVAC systems in harsh/seacoast environments, ultimately resulting in reduced electric demand and longer equipment service life. The ability to develop, test, qualify, and evaluate new corrosion prevention coatings for HVAC coils has the potential to reduce testing costs and more easily introduce better technologies as they are developed. Currently, prospective technologies are developed much faster than they can be tested and qualified. Since the highest maintenance costs for DoD HVAC equipment results from corrosion, a gain in implementation of new coatings and the informed assessment of CI and corrosion risk will be beneficial to DoD. Coatings that prevent coil corrosion have the potential to reduce DoD energy intensity by 600 kWh per thousand GSF¹ and energy and equipment repair costs by $100 million per year. Along with energy savings, a considerable improvement in reliability and cooling & heating performance can also be expected. (Anticipated Project Completion - 2027)

¹ Energy Information Administration, data for 2012; released 2016, https://www.eia.gov/consumption/commercial/data/2012/c&e/cfm/e5.php