A HVAC system (100) includes a housing (10) with at least one first inlet (20) and at least one second inlet (30) formed thereon, at least one first door (20a), at least one second door (30a) and an intermediate door (40). The first inlet (20) and the second inlet (30) is for ingress of a first fluid stream and a second fluid stream inside the housing (10). The first door (20a) and the second door (30a) moves with respect to the first inlet (20) and the second inlet (30) respectively to define an open configuration, a closed configuration and a partially open configuration thereof. The intermediate door (40) is disposed between the first inlet (20) and the second inlet (30) and moves between a deployed and an un-deployed configuration to respectively disrupt and allow fluid flow there across. The intermediate door (40) is a sliding door.