CODE WARS: Press-Connect Fittings VS. Brazing for Refrigeration
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There has been a “code war” raging over eliminating the use of listed press-connect fittings for refrigeration currently allowed by the Uniform Mechanical Code (UMC). ACCA’s Codes Subcommittee has been diligently monitoring this development and speaking in support of the continued use of press connect fittings as a viable and safe option to brazing.
Requirements for Refrigerant Connections
For the last two editions (2018 & 2021), the UMC has allowed press-connect fittings for copper or copper alloy pipe joints, in addition to brazing and other approved methods. Such fittings are also required to comply with UL Standard 207, which requires laboratory tests to verify robustness under extreme operating conditions to ensure safe performance.
Past Crusades Against Press-Connects for Refrigeration
During the development of the 2018 and 2021 UMC editions there have been numerous requests submitted to IAPMO to delete press-connect fittings from the UMC’s list of acceptable options. These submittals have come from a single individual representing a testing organization offering brazing testing and certification. Such activity has been supported by various California pipe trades including the United Association. All attempts to delete this option have been rejected by the UMC Technical Committee (TC), and appeals to the IAPMO Standards Council were also denied. Those opposed to allowing press-connects claim that such fittings may leak over time due to potential deterioration of the elastomeric O-ring seal after several decades. However, to date there has been no evidence or field data presented, even anecdotally, to suggest such fittings have a problem.
ASHRAE Research Concludes Press-Connects Are Safe
There is accepted industry research which concludes that press-connect fittings are one of the most reliable methods for joining refrigerant piping. This conclusion is contained in ASHRAE Research Project (RP-1808). The report concluded that press-connects were 400 percent tighter than the definition of a hermetically sealed joint per ISO Standard 14903.
ACCA’s Position on Brazing vs. Press-Connects
ACCA’s Codes Subcommittee has supported the UMC’s option of allowing listed press-connect fittings for refrigeration, in addition to brazing. Many HVAC professionals find the press connect fittings increase their company’s productivity. Additionally, in some situations, brazing does not always represent a viable option due to several factors:
- Confined spaces without proper ventilation
- Lack of a “fire spotter” (cannot braze alone)
- Combustible construction or materials at the job site
- Locations where open-flames are prohibited
It should be pointed out that listed press-connect fittings must be connected with a manufacturer-specified tool according to installation instructions. Just as with any product, improper installation can lead to failures, which is also the case if brazing is not properly conducted and verified by a trained qualified person.
Press-Connect Opposition for A2L Refrigerants
In preparation for the 2024 UMC edition, comprehensive coverage has been proposed for A2L “mildly flammable” refrigerants for use in home comfort systems. As before, attempts are being made to only allow brazed joints. In response, ACCA and the HVACR industry are strongly opposed to elimination of press-connects, even for A2L refrigerants, citing the above ASHRAE research’s conclusions.
May 2022 – The Next Battle
ACCA anticipates that those opposed to press-connects will submit public comments to once again try to convince the UMC TC that such fittings should be eliminated from the UMC. The TC will meet in May 2022 to review public comments submitted on its proposals and make their final recommendations for the 2024 UMC. We anticipate that the opponents will file an appeal with the IAPMO Standards Council, who has the final say on approving what will appear in the 2024 edition. “It ain’t over ‘til it’s over,” to quote Yogi Berra.
ACCA will issue field reports from the “front lines” after the above May 2022 meeting and beyond. If you have any questions or comments, please contact ACCA’s Manager of Codes & Standards at david.bixby@acca.org.
ACCA is fighting for you!
Posted In: ACCA Now, Safety, Technology
