FIELD NOTE · SUPPLEMENTAL SET
The R-410A install deadline is still live until July 27
ISSUEDJULY 11, 2026DRAWN BY THE NIGHTLY SWEEP
The January 1, 2026 installation deadline for R-410A equipment stops existing on July 27, 2026, and nothing at all replaces it. EPA removed it outright.
The final rule sits at 91 FR 31284, published May 26, 2026 and effective July 27, and what it does to 40 CFR 84.54(c)(1) is a deletion rather than another extension. Residential and light commercial systems whose specified components were manufactured or imported before January 1, 2025 may then be installed with no end date at all.
EPA says so in section III.H without hedging: "The EPA is finalizing, as proposed, the removal of the deadline for installing residential and light commercial AC/HP systems when using equipment that was domestically manufactured or imported into the United States before January 1, 2025." There is no replacement date.
So the deadline the trade planned around was itself already an extension. The 2023 Final Rule at 88 FR 73098 barred installing these systems above 700 GWP starting January 1, 2025, and an interim final rule published December 26, 2023 at 88 FR 88825 pushed the installation date out a year. That extension took effect on schedule and governed roughly seven months of 2026, which means every bulletin and plan check table written in that window was right when it was written.
The number the trade prints for R-454B is 466, and it is repeated across trade coverage, OEM white papers and distributor material. EPA's own reference table says 465, and that table is what the 700 threshold gets measured against. The difference changes no outcome. It changes where the number in a submittal came from.
R-454B is 68.9 percent HFC-32 and 31.1 percent HFO-1234yf, and both it and HFC-32 are classified A2L under ASHRAE Standard 34, low toxicity and mild flammability. Trane, Carrier, Lennox and Rheem went to R-454B in US residential split systems, and Daikin is the major US OEM using HFC-32. The manufacturer picked the refrigerant. It did not pick the schedule.
Neither was granted. Section III.F.2 reads: "In this final rule, the EPA is not making any changes to the treatment of new condensing units in the residential and light commercial AC/HP subsector." Condensing units stay one of five specified components, outside the manufacture, import, sale, distribution and export restrictions, so that "a homeowner can choose to replace their failed condensing unit rather than purchase a whole new system."
None of the reasoning is about refrigerant performance. The rule states that "The AIM Act is inherently inflationary," and the condensing unit discussion leans on a Presidential Memorandum on emergency price relief, citing its direction to eliminate requirements that raise the cost of home appliances. Cost of living decided this one, and the equipment followed.
A2L refrigerants "are sold in re-designed 20-pound cylinders rather than the traditional 30-pound cylinders used for other refrigerants," per that memo, and Worthington Enterprises is "the sole domestic cylinder manufacturer in the United States." EPA names three factors rather than one: demand above forecast, the service cylinder shortage, and possible tariff effects. The same memo records that there was sufficient R-454B overall while the field could not get it in service cylinders, and that Honeywell separately said its own domestic production was not enough to meet demand.
Honeywell announced a 42 percent surcharge on R-454B in April 2025, a figure EPA carries from trade press rather than from anything filed. By August, EPA observed online retail R-454B running 50 to 60 percent below June prices, and Carrier said orders were being fulfilled within two weeks.
Which standard governs turns on how many dwelling units one system serves. ASHRAE 15.2-2022 applies to A2L systems serving a single dwelling unit, one to one, high-rise and low-rise multi-residential alike. ASHRAE 15-2022 takes commercial space, nonresidential or common space in a multi-residential building, and any system serving more than one dwelling unit.
That split is where the most quoted sentence in the guideline gets misread. Asked whether A2L systems under 6.6 pounds of charge are exempt from EDVC calculations, LADBS answers "No. For A2L systems covered under ASHRAE 15, EDVC calculations (per Sec. 7.6) are required regardless of the system charge." The answer then continues: "For A2L systems covered under ASHRAE 15.2, please refer to the charge limit compliance flow path in Sec. 9." Most residential replacement work is one to one and runs that Sec. 9 flow path.
The worked examples want the same care, because LADBS did not run them all on the same refrigerant. The ASHRAE 15 Equation 7-8 sample is R-454B: 110 square feet at an 8 foot ceiling gives 880 cubic feet, and against the LFL of 18.5 pounds per 1,000 cubic feet that LADBS reproduces from ASHRAE 34 Table 4-1, and with the concentration factor of 0.5 and occupancy factor of 1.0 that LADBS applies, the EDVC comes out at 8.14 pounds. The system charge in that example is 4.75 pounds. It passes.
Sample calculations B1 and B2 look like the same problem and are not, though not in the way the numbers first suggest. B1 is the R-454B case: a 3.75 pound charge against an m1 of 4.1 lbm drawn from Table 9-1, and LADBS works it out to a pass. B2 runs R-32 at 4.75 pounds, fails that same 4.1 lbm trigger, and carries on to an m2 of 35.1 lbm. So 4.1 lbm is the trigger both of those worked examples run against. Only the 35.1 lbm figure belongs to the R-32 example alone.
LADBS also makes the refrigerant a drawing set problem: "Approved plans using A1 refrigerant systems shall be re-submitted and re-approved by Building and Safety, Mechanical Plan Check to accommodate another refrigerant type if the A1 refrigerant is not available at the time of construction." Revising previously approved plans means resubmittal, approval and "all additional plan check fees," with responsibility for full compliance on the owner. Not every A2L install lands in plan check, though: LADBS says that "If the installation meets the express permit qualifications, an express permit can be obtained."
On the equipment side, CARB's fact sheet ties its compliance dates to when the equipment was manufactured, not to when it is sold or installed.
The federal leak repair rule keeps getting attached to residential work as well. Requirements at 40 CFR 84.106 began January 1, 2026 on appliances holding 15 pounds or more, and EPA's January 2026 fact sheet on them carves out this trade in one sentence: "Refrigerant-containing appliances used in the residential and light commercial air conditioning and heat pumps subsector are not covered under these requirements."
VRF got nothing from the May rule either. LADBS Table 1 gives VRF a manufacture and import date of January 1, 2026 and an installation compliance date of January 1, 2027, with installation permitted until January 1, 2028 where a building permit with an approved A1 system was issued before October 5, 2023.
The final rule sits at 91 FR 31284, published May 26, 2026 and effective July 27, and what it does to 40 CFR 84.54(c)(1) is a deletion rather than another extension. Residential and light commercial systems whose specified components were manufactured or imported before January 1, 2025 may then be installed with no end date at all.
EPA says so in section III.H without hedging: "The EPA is finalizing, as proposed, the removal of the deadline for installing residential and light commercial AC/HP systems when using equipment that was domestically manufactured or imported into the United States before January 1, 2025." There is no replacement date.
So the deadline the trade planned around was itself already an extension. The 2023 Final Rule at 88 FR 73098 barred installing these systems above 700 GWP starting January 1, 2025, and an interim final rule published December 26, 2023 at 88 FR 88825 pushed the installation date out a year. That extension took effect on schedule and governed roughly seven months of 2026, which means every bulletin and plan check table written in that window was right when it was written.
2,088 against a limit of 700
EPA's Technology Transitions GWP Reference Table lists R-410A at 2,088 and R-454B at 465, both calculated, with HFC-32 at 675 on IPCC 2007. The threshold in 84.54(c)(1) is a global warming potential of 700 or greater. Which means R-410A never sat marginally over that line: 2,088 divided by 700 is 2.98, so the equipment this rule protects carries a refrigerant about three times the limit written to keep it out of new systems.The number the trade prints for R-454B is 466, and it is repeated across trade coverage, OEM white papers and distributor material. EPA's own reference table says 465, and that table is what the 700 threshold gets measured against. The difference changes no outcome. It changes where the number in a submittal came from.
R-454B is 68.9 percent HFC-32 and 31.1 percent HFO-1234yf, and both it and HFC-32 are classified A2L under ASHRAE Standard 34, low toxicity and mild flammability. Trane, Carrier, Lennox and Rheem went to R-454B in US residential split systems, and Daikin is the major US OEM using HFC-32. The manufacturer picked the refrigerant. It did not pick the schedule.
Two petitions to close the condensing unit path, and both lost
The trade also believes that a failed outdoor unit on an R-410A system now forces a whole system changeout. EPA had that question in front of it twice. A chemical manufacturer petitioned to close the replacement path, and a coalition of trade associations petitioned to have condensing units designed for use with a single condenser and a single evaporator treated as new system installs, narrowed by a supplemental letter dated April 30, 2024 to units under 65,000 BTUs, which EPA cites in the rule.Neither was granted. Section III.F.2 reads: "In this final rule, the EPA is not making any changes to the treatment of new condensing units in the residential and light commercial AC/HP subsector." Condensing units stay one of five specified components, outside the manufacture, import, sale, distribution and export restrictions, so that "a homeowner can choose to replace their failed condensing unit rather than purchase a whole new system."
None of the reasoning is about refrigerant performance. The rule states that "The AIM Act is inherently inflationary," and the condensing unit discussion leans on a Presidential Memorandum on emergency price relief, citing its direction to eliminate requirements that raise the cost of home appliances. Cost of living decided this one, and the equipment followed.
The service cylinder went from 30 pounds to 20
EPA's Stratospheric Protection Division wrote up the 2025 shortage in a memo dated September 18, 2025, and the memo puts the contractor at the center of it rather than the OEM: "the impacts of the shortage have affected contractors the most since material was scarcely available in service cylinders for use in the field." Equipment ships pre-charged from the factory. The field portion comes off a service cylinder, which is the exact point that jammed.A2L refrigerants "are sold in re-designed 20-pound cylinders rather than the traditional 30-pound cylinders used for other refrigerants," per that memo, and Worthington Enterprises is "the sole domestic cylinder manufacturer in the United States." EPA names three factors rather than one: demand above forecast, the service cylinder shortage, and possible tariff effects. The same memo records that there was sufficient R-454B overall while the field could not get it in service cylinders, and that Honeywell separately said its own domestic production was not enough to meet demand.
Honeywell announced a 42 percent surcharge on R-454B in April 2025, a figure EPA carries from trade press rather than from anything filed. By August, EPA observed online retail R-454B running 50 to 60 percent below June prices, and Carrier said orders were being fulfilled within two weeks.
Los Angeles is still printing a deadline that ends on July 27
LADBS Guideline P/MC 2026-007, "Guideline: HVAC Systems Using A2L Refrigerants," reference CMC 1104.6, took effect 07-01-2024 and was revised 01-01-2026, and its Table 1 still carries January 1, 2026 as the installation compliance date for field charged systems, which is the residential replacement row. The guideline is still correct today. It stops being correct on July 27, when the federal rule takes effect underneath it, and the plan check engineer reading a submittal in Los Angeles will still be working from the guideline.Which standard governs turns on how many dwelling units one system serves. ASHRAE 15.2-2022 applies to A2L systems serving a single dwelling unit, one to one, high-rise and low-rise multi-residential alike. ASHRAE 15-2022 takes commercial space, nonresidential or common space in a multi-residential building, and any system serving more than one dwelling unit.
That split is where the most quoted sentence in the guideline gets misread. Asked whether A2L systems under 6.6 pounds of charge are exempt from EDVC calculations, LADBS answers "No. For A2L systems covered under ASHRAE 15, EDVC calculations (per Sec. 7.6) are required regardless of the system charge." The answer then continues: "For A2L systems covered under ASHRAE 15.2, please refer to the charge limit compliance flow path in Sec. 9." Most residential replacement work is one to one and runs that Sec. 9 flow path.
The worked examples want the same care, because LADBS did not run them all on the same refrigerant. The ASHRAE 15 Equation 7-8 sample is R-454B: 110 square feet at an 8 foot ceiling gives 880 cubic feet, and against the LFL of 18.5 pounds per 1,000 cubic feet that LADBS reproduces from ASHRAE 34 Table 4-1, and with the concentration factor of 0.5 and occupancy factor of 1.0 that LADBS applies, the EDVC comes out at 8.14 pounds. The system charge in that example is 4.75 pounds. It passes.
Sample calculations B1 and B2 look like the same problem and are not, though not in the way the numbers first suggest. B1 is the R-454B case: a 3.75 pound charge against an m1 of 4.1 lbm drawn from Table 9-1, and LADBS works it out to a pass. B2 runs R-32 at 4.75 pounds, fails that same 4.1 lbm trigger, and carries on to an m2 of 35.1 lbm. So 4.1 lbm is the trigger both of those worked examples run against. Only the 35.1 lbm figure belongs to the R-32 example alone.
LADBS also makes the refrigerant a drawing set problem: "Approved plans using A1 refrigerant systems shall be re-submitted and re-approved by Building and Safety, Mechanical Plan Check to accommodate another refrigerant type if the A1 refrigerant is not available at the time of construction." Revising previously approved plans means resubmittal, approval and "all additional plan check fees," with responsibility for full compliance on the owner. Not every A2L install lands in plan check, though: LADBS says that "If the installation meets the express permit qualifications, an express permit can be obtained."
The date on the service truck is January 1, 2030
California runs its own schedule and the AIM Act does not preempt it. Health and Safety Code 39735(b), added by SB 1206 in 2022, caps bulk HFCs and bulk blends sold or distributed in California at 2,200 GWP from January 1, 2025, then 1,500 from January 1, 2030, then 750 from January 1, 2033. R-410A at 2,088 clears the first and fails the second. Reclaimed HFCs are excepted under 39735(d)(1)(A).On the equipment side, CARB's fact sheet ties its compliance dates to when the equipment was manufactured, not to when it is sold or installed.
The federal leak repair rule keeps getting attached to residential work as well. Requirements at 40 CFR 84.106 began January 1, 2026 on appliances holding 15 pounds or more, and EPA's January 2026 fact sheet on them carves out this trade in one sentence: "Refrigerant-containing appliances used in the residential and light commercial air conditioning and heat pumps subsector are not covered under these requirements."
VRF got nothing from the May rule either. LADBS Table 1 gives VRF a manufacture and import date of January 1, 2026 and an installation compliance date of January 1, 2027, with installation permitted until January 1, 2028 where a building permit with an approved A1 system was issued before October 5, 2023.