A building’s hydronic HVAC system is rarely just the sum of its parts. The system is comprised of chillers, boilers, pumps, VFDs, AHUs, and valves that create a loop through which water is circulated to control the building’s temperature and its occupants’ comfort. In this loop, each component is a node that has an effect not just on the one next to it but on every other one, regardless of how far they are from each other. In fact, the nodes furthest from each other may impact each other the most. Variable speed pumps, for example, surrender much of their part-load efficiency if the wrong balancing valves are installed at the terminal units. Too often, systems are designed and components specified as though this loop is made of discrete nodes. Consequently, building owners continue to install inefficient systems and then struggle to find lasting solutions to chronic problems like hot spots, high utility bills, and constant maintenance calls.
A system composed of synergistic components, on the other hand, enhances the efficiency of the entire loop. Pressure independent control valves (PICVs) installed at the AHUs tightly control the water temperature entering and exiting the unit’s coils, allowing the chiller’s oil-free variable speed compressor to work as efficiently as possible. VFDs on the pumps supply only as much water as is demanded to take advantage of part-load conditions to save energy. All the while, each component collects valuable data on energy usage, flow, pressure, and temperature for the BMS to aggregate and use to make decisions about predictive maintenance, fault detection, and comfort.