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B Y J O H N B U F F A P lanning, selecting and installing mechanical insulation for commercial HVAC systems entail a variety of mechanical applica- tions. Commercial HVAC systems require properly installed mechanical insulation on pipes, ducts, tanks and equipment. The mechanical insulation on these systems controls the tempera- ture variation that helps limit heat gain or loss on surfaces operating above or below ambient temperature. It is within an HVAC system that some of the largest energy savings can be attributed. Specific insulation or accessory prod- ucts are specified and the mechanical in- sulation contractor must thoroughly un- derstand the requirements for installing the products. According to the National Mechanical Insulation Committee, the mechanical insulation contractor must obtain and review the Material Safety Data Sheets for all materials used on the project. Although code requirements are the responsibility of the design profes- sional, a knowledgeable mechanical insulation contractor should understand the code requirements, as well. PRE-WORK CONSIDERATIONS, PLANNING A mechanical insulation system is designed to operate under a given set of operating and environmental conditions. If the design team does not perform its due diligence to gather the necessary in- formation to develop the correct design conditions for the specific application, there is a good chance the system will fail at some time during the operation. The project team should consider access to the area of installation. Close coordination with other trades to minimize congestion in the work area is required. Project readiness is also sometimes an issue for installing mechanical insulation. Some products such as adhesives, tapes, mastics and coatings require that they be applied above a certain temperature. Whether the HVAC system is indoor or outdoor, the mechanical insulation contractor should be aware of the limitations and make the other trades aware so they can coordinate and schedule around the weather. INSULATION MATERIALS Due to a wide variety of pipe insulation options available, mechanical system engineers are in the unique position to choose the specific type of insulation system best suited for the needs of the individual application. This type of individualized selection maximizes the benefits and minimizes any potentially negative consequences that a lack of proper insulation could create. Common mechanical insulation ma- terials include fiberglass, mineral wool, rigid or flexible foam, polyethylene or other polyurethane-based insulation types, calcium silicate, cellular glass and aerogel. This range of material is able to offer the ideal solution for any type of mechanical system. THERMAL RESISTANCE AND HEAT LOSS Increasing the thickness of an insulat- ing layer increases thermal resistance. To calculate the R-value of a multi- layered installation, one must add the manufacturer's recommended R-values of the individual layers. Manufacturer R-values only apply if the insulation is installed properly. According to the 2012 IECC Section C404.5, hot water piping should be insulated with at least one-inch thick of insulation having a conductivity not exceeding 0.27 Btu per inch/h × ft2 × F. The first eight feet of piping in a non-hot water supply temperature maintenance system served by equipment without integral heat traps should be insulated with .5-inch thick of insulation material having a conductivity not exceeding 0.27 Btu per inch/h × ft2 × F. INSTALLING MECHANICAL INSULATION Mechanical insulation is commonly installed on HVAC piping including chilled water piping, condenser water piping, heating hot water piping, steam piping, refrigerant piping and conden- sate drains. Each product requires a specific type of insulation for optimal performance. 1. Piping located outside that is partially covered with fi berglass, an aluminum jacket, PVC fi tting covers and insulation covering the valves. 2. Water piping with fi berglass insulation without corners covered with aluminum jacketing. 3. HVAC piping located in a mechanical room with a fi berglass pipe covering. PVC fi tting covers and valves are covered with Armafl ex insulation. 4. Heat-traced cooling tower water piping with fi berglass insulation and aluminum jacketing. Peak Performance Keeping HVAC systems in top shape with properly installed, maintained insulation 2 1 HVACPproducts.com HVAC & Plumbing Product News \ Summer 2017 16