MSC Revives Old System to Provide Temporary Cooling on Reno Project

On a recent lab and office renovation project, it quickly became clear that the fast-track project schedule was in jeopardy. Floors, case work, and other finishes were due to be installed, but the new HVAC system was not yet in place. Many manufacturer warranties require specific climate conditions at installation because temperatures and humidity that are too high or too low can adversely affect the finished product.

Concerned project managers considered their options. Rental air conditioning units would be prohibitively expensive, not only for their high leasing fees but for the cost to provide power and temporarily duct them into the building. Smaller spot coolers can only cool individual spaces, and having many of them would, again, require power and ducting for heat rejection, and condensate buckets would have to be constantly emptied. For their third option, PMs turned to several HVAC DX package units that had been disconnected and slated for removal, but were still in place. Even though the old duct work had already been removed, could these units be temporarily brought back to life to provide cooling? MSC was called in to find out.

MSC technicians were able to get the units up and running with a bit of work and cleaning. They devised a way to tie in to the new duct system with a few temporary cross-connects to get cooling where it was needed. The units were controlled by return air temperature back at the unit. Extra MERV 8 filter media was used to keep coils free of construction dust and debris. The filter media was changed and units were checked on a weekly basis while floors, case work, and finishes were installed, along with the new HVAC equipment. Once the new units were ready to go online, the duct work spool pieces were disconnected and the old units removed. Though there was some added expense, revival of the old HVAC system saved many thousands of dollars, not to mention the project end date.