Heat transfer is an important consideration when selecting a protective coating for HVAC-R condensers or evaporators. A protective coating, when applied properly, can extend the life of HVAC-R coils by preventing corrosion with negligible impact on heat transfer.
In 2017, we participated in a wind tunnel test for our P-413 baked phenolic epoxy coating. This test was conducted by an OEM using their own coils.
The test procedure followed ASHRAE Standard 33-2000 (Methods of Testing Forced Circulation Air cooling and Air Heating Coils)*:
- The uncoated coil was tested in the OEM’s wind tunnel.
- Air flow rate, inlet air temperature, water flow rate, and inlet water temperature were measured.
- The coil was coated by Heresite and returned to the OEM for testing.
- The coil was tested in the OEM’s wind tunnel under nearly identical conditions.
The results:
- The air flow rate, inlet air temperature, water flow rate, and inlet water temperature were within the margin of error of the testing.
- At the same testing condition, the test was not able to statistically discern a difference between the uncoated coil and the coated coil.
What it means for you:
While P-413 has demonstrated its ability to provide superior protective performance in the ISO 20340 test, the coating does not impact heat transfer in any material way (<1%).
If you have questions about this test or selecting the coating that is recommended for your environment, please give us a call.
* ASHRAE Standard 33 presents a method of test for use in laboratory testing of forced circulation air-heating and air-cooling coils. The 2016 edition of this standard was updated with assistance from the members of the product subsection Forced Circulation Air-Cooling & Air-Heating Coils (ACHC) at Air-Conditioning, Heating and Refrigeration Institute (AHRI). This method of test is used in conjunction with the performance metrics in AHRI Standard 410 as part of AHRI’s ACHC certification program. This standard was prepared by ASHRAE Standard Project Committee (SPC) 33. The cognizant technical committee is ASHRAE TC 8.4, Air-to-Refrigerant Heat Transfer Equipment.