Nu-Calgon - A/C Re-New, formerly Zerol® Ice, has been used successfully for many years to improve the performance of air conditioning and refrigeration systems. A/C Re-New provides significant saving in energy use. It also quiets noisy systems and extends the life of the system. It is a lubricant that blends with the systems oil, lasting for the life of the equipment.A/C Re-New can be used in air conditioning and refrigeration applications. The pressurized package, 4057-50, is designed specifically for R-22 applications. This canister is pressurized with R-22 to assist in installation for systems up to 5 tons. Multiple cans should be used to treat larger commercial systems such as packaged units, split system or larger refrigeration systems. For other refrigerants such as R-410A, use the unpressurized package, 4057-55. It can be easily installed using the A/C Re-New Injector.