Building Advisor Case Study Rooftop Units

Building Advisor diagnostics and reporting were deployed to provide ongoing commissioning on newly installed rooftop units at a one-story community center housing offices, a gymnasium, and community rooms. Five RTUs were connected to the cloud-based system for monitoring and diagnostics. Almost immediately, several problems with RTU scheduling, compressor cycling, and simultaneous heating and cooling demands were found leading to controls adjustments to reduce energy consumption and costs. Only 10 HVAC sensors and settings on each RTU (a total of 50 points) were set up for monitoring: compressor status, cooling demand, gas valve status, heating command, outside air temperature, power status, return air temperature, suction line temperature, supply air temperature, and fan status. Despite the low level of instrumentation, several key issues were diagnosed.