News & Updates

Some interpretation requests have been sent to ASHRAE SSPC 15 regarding paragraph 7.5.1.2 on VRF or Split DX equipment (piping, fan coil units, VRF distribution boxes) located above the ceilings of public corridors and lobbies. As a result, ASHRAE recently published a clarification in the form of a formal interpretation (IC-15-2002-13) found here.

The interpretation agrees that refrigerant components such as VRF distribution boxes located ABOVE a false ceiling are not considered to be "IN" the corridor or lobby, and are thus allowed. As a result, components such as refrigerant piping, fan coil units, and distribution boxes can continue to be installed above corridor and lobby pathways. There was confusion surrounding the use of the work "in" [corridors or lobbies], however, "in" is not the same as "above".

The history of this paragraph has always dealt with refrigerated equipment entirely located on the floor of a lobby or corridor, such as vending / ice machines or water-coolers, or equipment that could impede someone's avenue to exit a building. These systems must be "Unit Systems," defined as self-contained systems where all the components of the system were factory assembled and charged at the factory. With some of these vending / ice machines and water-coolers now turning to ultra-low GWP refrigerants such as R-290 (Propane), ASHRAE SSPC 15 felt it necessary to limit the amount of any Class A2, 2, or 3 refrigerants in those types of systems.

North Central Texas Council of Governments (NCTCOG) has recently approved Regional Amendments to the 2024 International Mechanical Code that are favorable for R-32 DX Split systems and R-32 Variable Refrigerant Volume (VRV) installations. Per the NCTCOG’s website, they state: “NCTCOG's Regional Codes Coordinating Committee (RCCC) and its five advisory boards conducted multiple meetings to review the latest editions of the model codes and develop regional amendments. Their review and recommendations are endorsed by NCTCOG's Executive Board. NCTCOG encourages jurisdictions in North Central Texas to adopt the following model construction codes along with their respective regional amendments as expeditiously as their local code adoption process will allow.

ASHRAE Standard 15 has released Addendum A to the 2024 standard, further clarifying ASHRAE's position regarding vertical A2L refrigerant piping, and the fact that they do not need to be installed in rated ventilated shafts. The new Shaft Alternative clarifies that, as long as the refrigerant piping has been tested to section 9.13, a shaft is not required. Section 9.13 of ASHRAE 15 has requirements that are very similar to conventional manufacturer requirements for refrigerant piping, and therefore should not impact installations. DXS does recommend that engineers and installers review section 9.13 to ensure compliance, as not all manufacturers may have requirements up to that standard.

On November 12^th, 2024, the Board of Building Regulations and Standards (“BBRS”) issued an advisory document pertaining to HVAC equipment utilizing A2L refrigerants. The document reiterates that the published version of the 10th edition code did adopt the latest referenced standards pertaining to A2Ls, including ASHRAE 15 and 34 2022, as well as UL/CSA 60335-2-40 2022, but admits that there are still conflicts between these standards and certain provisions of IMC 2021, which BBRS is working through (referring to the remaining DXS code change proposals still making their way through the process).
 
However, BBRS then advises that HVAC installations abiding by these updated standards, including ASHRAE 15 2022, are approvable by inspectors pursuant to 780 CMR 104.11. The document concludes with this statement: “BBRS is of the opinion that equipment utilizing A2L refrigerants when installed in compliance with the updated safety and design standards, is legal and appropriate for installation in Massachusetts based upon the 10th Edition Building Code”.
 
This advisory document is key to the progression of A2L adoption in Massachusetts, allowing designers to use the latest and safest language surrounding A2Ls, which is ASHRAE 15. This solves key conflicts with IMC 2021, such as R-32 and R-454B being classified as A2 refrigerants, the dated language requiring ventilated shafts, the lack of proper formulas for EDVC quantities, and more. This compliance path will eventually be officially written into the 10^th Edition Building Code as an amendment to Chapter 28, but in the meantime, this advisory document allows project teams to begin designing with A2L refrigerants. Note that the 9^th Edition Building Code, based on IMC 2015 and ASHRAE 15 2013, remains an issue for HVAC equipment of all types using A2L refrigerants.

The tenth edition building code was filed with the Secretary of State on Tuesday, September 24, 2024, and became effective on October 11, 2024. Concurrency with the 9^th Edition of the Building Code has been extended until June 30^th, 2025. However, the 9th Edition, being based on IMC 2015 and ASHRAE 15 2013, does not have references or allowances for A2L refrigerants. Projects wishing to use HVAC equipment with A2L refrigerants will need to adhere to the 10^th Edition Building Code or attempt to petition BBRS under a 9^th Edition compliance.

TSSA has adopted the new version of CSA B52-2023, and here is a link to their website that includes their code adoption document along with additional details. TSSA will allow the industry to take advantage of the new code from the publication date (August 15, 2024), meaning that applications submitted with reference to CSA B52-2023 will now be accepted and considered during inspections.

Consistent with our commitment to decarbonize buildings with high-efficiency heat pumps, ventilation, and automation, DXS Service is also committed to supporting the circular economy of refrigerants. Transitioning to lower GWP refrigerants such as R-32 is key for new systems moving forward, however, there are millions of pounds of R-410A refrigerant currently sitting in HVAC equipment on existing buildings across North America. One of the most important steps that we can take as an HVAC industry to reduce emissions from refrigerants, is to ensure that as many of those pounds of R-410A get properly removed from the field (at end of life or during repairs) and taken to certified reclaim facilities. Doing so properly prevents that refrigerant from being leaked into our atmosphere, but it also reduces the amount of new virgin refrigerant that must be manufactured, and the energy and emissions required to do so.

On July 9^th 2024, BBRS voted in favor of the remaining 6 of 8 DXS code change proposals submitted in March (see previous news segments below). As a result, BBRS has now voted in favor of all DXS code change proposals, almost in their entirety, with only a few modifications. Below is an overview of the accepted proposals:

As anticipated, the EPA plans on providing a one-year sell-through extension for VRF systems, similar to the one-year sell-through extension already in place for mini/multi-splits and other air-conditioners and heat pumps. As a result, VRF systems using R-410a can be installed through 2026, so long as they were manufactured in the U.S. or imported into the U.S. prior to 1/1/2026. This rule is out for proposals with a 30-day public comment period but is expected to be put in place as-is.

The International Code Council (ICC) voted on multiple items for the 2024-2026 Code Development Cycle during the April 2024 Committee Action Hearing (CAH1). ICC has unanimously voted (14-0) to update the language of IMC clause 1109.2.5 Refrigerant Pipe Shafts to better align with ASHRAE 15 2022, where exception (2) to the requirement for shafts is no longer limited to only A1 refrigerants. The change allows A2L refrigerants to be run in wall cavities instead of being forced to run in shafts, so long as the refrigerant concentration limits are met in any occupied space through which the piping passes.