New refrigerants are exposing undersized ducts in Texas houses

On September 11, 2026, ACHR News published a field report by Paolo Weston on the move to A2L refrigerants. New residential systems use R-454B or R-32 instead of R-410A, under the EPA limit that applied to equipment manufactured from January 1, 2025. Weston’s point is that the new equipment is less willing to hide an undersized duct system, a charge that was guessed from a gauge, or a condenser and coil that were never matched.

Dallas–Fort Worth has a lot of the housing he is describing: equipment and ductwork in a hot attic, often resized one box at a time. Greater Austin adds long flex runs in newer suburbs and older houses that were never ducted well. A high-efficiency system on those ducts can run and still leave a back bedroom behind. The article’s practical test is to measure static pressure and airflow before the equipment is chosen, weigh the refrigerant charge for the line length, and confirm the indoor and outdoor units are an AHRI-matched pair.

Ask whether anyone measured the ducts, not only the square footage. Ask whether the factory charge covers your line set. Ask for the matched-system rating and for startup numbers written down. ACHR News noted that a missed match, a skipped manufacturer A2L training record, or a line set the instructions do not allow can put the parts warranty at risk, and that the denial often shows up years later when a major part fails.

None of that is a reason to replace a system that only needs a repair. It is a reason to treat a replacement in this climate as a duct-and-equipment decision. If the attic cannot move the air, you should hear that before the equipment is sold.