Tappan packaged air conditioner Model P7RD utilizes R-410A refrigerant and all-aluminum microchannel condenser coil technology. According to the manufacturer, advantages of microchannel coils include lighter weight, smaller size, better durability, and greater reliability in corrosive environments. The 13 SEER packaged air conditioner features a small footprint for ease of installation. A wire coil guard coated with Earth-friendly epoxy and a never-rust mesh hail guard protect the coil from being damaged by balls, lawnmowers, hail, etc. Optional backup heat is provided by an electric heat strip, which provides up to 20 kW of heat output. The unit is composed of galvanized steel with a polyester urethane finish. The 950-hour salt spray finish is 1.5 mil thick and resists corrosion 50 percent better than standard finishes, claims the company. The P7RD model features a 10-year all-parts warranty and 10-year Tappan Tough Quality Pledge to replace the unit if the compressor fails (product registration required).