The Model 400 is designed to work as a standalone HVAC control system or work in conjunction with the TELSEC ESB2 Environmental Controller to provide a comprehensive monitoring and control system for telecom/broadband facilities. Multiple HVAC units can be grouped by the area they serve to provide lead/lag/standby functionality per zone. HVAC systems with economizers can take advantage of Quest’s patented economizer control algorithm to maximize the amount of time outside air can be used to maintain the temperature in each zone. The Model 400 provides the necessary redundancy for critical facilities while providing optimization that reduces the energy consumption of HVAC equipment. Up to 16 Model 400 HVAC Controllers can be networked to the TELSEC ESB2.