DENVER - There are a lot of horror stories about permanent HVAC equipment that was operated while the building was under construction, and the resulting damage to the system. The question of whether a permanent system should be used at all during construction was pondered during a forum at the 2005 American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE) Annual Meeting.
The answer was no, it shouldn't be used during construction. Most of the talk centered on why.