CHANTILLY, Va. - The Sheet Metal and Air Conditioning Contractors' Association recently released a paper titled Temporary Uses (Early Start-Up) of HVAC Systems In Building Construction Projects. According to the paper, permanent HVAC systems are specifically designed to provide comfortable, clean air conditioning for a tightly enclosed, soundly constructed building and not buildings under construction.

Except for rare circumstances, it is not in the best interest of the building's owner to operate a permanent HVAC system for temporary heating or cooling purposes during construction. When using the permanent HVAC system for temporary heat construction, filter failures can cause insufficient protection of the permanent HVAC system, leaving excessive amounts of construction dust in the system.

Permanent HVAC systems are also not designed or constructed to dry wet surfaces. This misuse can result in subsequent indoor air quality problems associated with mold and other related airborne contaminants.

Early startup may void the warranty on the system's equipment and possibly reduce equipment life and operating efficiencies. According to SMACNA, total energy costs will generally be higher than the cost to use temporary heating, cooling, and dehumidification equipment currently available in the marketplace.

The paper is free to SMACNA members at

Publication date: 12/26/2005