R448A retrofit advisor: what should replace your R404A, R22 or R407C?

Not outright banned, but heavily restricted. Under retained F-Gas Regulation 517/2014, virgin R404A (GWP > 2,500) can't be used to service equipment with a charge of 40 tonnes CO₂ equivalent or more (≈ 10 kg of R404A) since January 2020. Reclaimed gas is still legal for service until 2030.

Almost never for R404A → R448A or R449A. The oil chemistry (POE) is the same, the operating pressures are close enough, and the compressor envelope tolerates the swap. The filter dryer is always replaced.

R448A and R449A run slightly more efficiently than R404A in MT applications (2-5% energy reduction is typical). The real saving usually shows up in the gas itself: reclaimed R404A prices are rising while R448A is in steady supply.

Both are excellent low-GWP options for new equipment but usually impractical as a retrofit. R290 is A3-flammable so the kit has to be designed for it. CO₂ runs at much higher pressures and needs completely different piping. For an existing R404A pack, R448A / R449A are nearly always the right answer.

R448A and R449A are zeotropic blends. The constituent gases boil and condense at different temperatures, so the refrigerant has a temperature "glide" of around 4-5 K across the evaporator. Two practical consequences: always charge as liquid, and the TXV superheat target shifts down slightly.

For a single MT cold-room condensing unit, typically 4-6 hours of downtime. We schedule retrofits early-morning or overnight on hospitality and retail sites so stock loss is minimal.