RectorSeal-090913-body.jpgRectorSeal has developed the SlimDuct RD-Series and the PD-Series, commercial rooftop ducting and support systems that are designed for multiple linesets as used with variable refrigerant flow and multi-split systems or any other conventional air-conditioning and refrigeration systems. The company says both series save more than 75% in labor when compared to the alternative of custom-fabricated galvanized sheet metal lineset ducting or other labor-intensive fabrications. The RD-Series comprises 20-gauge, roll-formed rectangular sheet metal lineset duct and fittings. It features a proprietary, anti-corrosive, scratch-resistant hot-dipped and chromium-free ZAM® coating (zinc, aluminum, and magnesium) a more durable and lighter weight alternative to galvanized steel. Widths for the RD-300, RD-450, RD-600, and RD-900 are 12, 18, 24 and 36 in, respectively and all are 5-1/8-in high. Based on a 3/8-in by 3/4-in lineset with 1/2-in insulation on both lines, the RD-Series can accommodate the following number of linesets: RD-300 (8), RD-450 (12), RD-600 (19), and RD 900 (25).   

The PD-Series is designed for smaller installations which do not warrant the larger metal lineset duct. It also serves as a transition to protect the lineset from where it exits the VRF condenser until it enters the RD-Duct. The PD-Series differs from the RD-Series in that it consists of UV, fire, and weather-resistant  ivory-colored extruded PVC round duct in 2 sizes only, PD-90 (3.5-in diameter) and PD-120 (4.7-in diameter), and is available in 39 in and 60 in lengths.