Primary / Secondary Pumping
Some large buildings have areas occupied during different time cycles, such as perimeter offices, interior zone areas, or restaurants.
To reduce operating costs, a primary / secondary pumping system may be used. The hydraulic system of each secondary circuit is isolated. Flow in a secondary circuit, such as the core areas, may be shut off along with the associated heat pumps, during unoccupied periods. Shutting off such a secondary pumping loop will not disturb the hydraulics of the system.