All major HVAC components in an aging building, including chillers, cooling towers, and boilers, eventually reach the end of their useful life and require replacement or tie-in to a campus central utility system. Major equipment replacement can be very disruptive to building occupants during the construction process. An important part in planning temporary utilities is a detailed interview with both the building occupants and the maintenance team that manages the building. Oftentimes utility demands in buildings change during the lifespan of a large piece of equipment. All of these components play a role in the building’s energy use and should be considered in designing both the temporary and permanent installations. Temporary thermal utilities can be served either by rental equipment or temporary connection to the campus utility loop. The correction factor for 140 degrees F operation is 22 percent for PVC and 50 percent for CPVC. At 180 degrees F, PVC is not an acceptable option, as the maximum PVC operating temperature is 140 degrees F. CPVC only has 25 percent of its published pressure at 73 degrees F. Typically, a temporary chiller or boiler doesn’t just “Plug-in,” so unless taps are available in the existing piping, a short shutdown or weekend outage may be required to set up the mechanical room for a tie-in to temporary equipment or the district loop.
Read more on facilitiesnet.com/hvac/article/H….