25LB R448A (R-448A) Refrigerant Gas | 5 Cylinders

Five cylinders is shelf stock, not job stock. It suits the independent outfit with a couple of trucks and a run of convenience stores, restaurant walk-ins and small rack systems — enough on hand to cover scattered service calls for a stretch without raising a purchase order every time the phone rings. One cylinder rides in each van, the rest wait in the cage. When the shelf is down to its last pair, order again.

Commercial refrigeration is where it lives: supermarket and convenience-store racks, display cases, reach-ins, walk-in coolers and freezers, low and medium temperature alike. It went in as the service and retrofit answer for R-404A and R-507 equipment, and turns up in converted R-22 machines too — US production of R-22 has ended, so those boxes get retrofitted or replaced. New build has moved on to carbon dioxide and the mildly flammable blends, so the work here is the installed base.

Charge it as liquid. The blend is zeotropic with appreciable glide, so a vapour draw shifts both the composition left in the cylinder and what reaches the system. Pull liquid however the cylinder valve in front of you allows, then throttle into the low side. Read dew point for superheat and bubble point for subcooling. After a leak, recover and weigh in a full charge rather than topping up. POE oil throughout. Pressures sit in R-404A territory, considerably above R-22, so match hoses, gauges and recovery kit to that.