For maximum control of indoor air conditions, SARAVEL offers the Triple-Deck Multizone. With this system a bypass plenum is added in conjunction with the conventional hot and cold air plenum. The mixture of return air and outside air is split after the supply fan and can either be heated, cooled, or go through the bypass plenum.

Multiple sets of mixing dampers, each consisting of a hot, cold, and a bypass damper, will be controlled by thermostats in the conditioned species. As an illustration, for a conditioned space demanding full cooling, the cold air damper will open and the bypass and the hot air dampers will close.

As the cooling load in the conditioned space reduces, the cold air damper will modulate closed and the bypass air damper will modulate open while the not air damper remains in the closed position. As the cooling load is reduced to zero, the cold air damper will close completely and the bypass air damper will open fully.