The HVAC discipline's auto-fitting options satisfy four distinct conditions:

1. Transition: The transition condition solves scenarios where route segments transition between shapes and sizes.
2. Elbow: The elbow condition solves scenarios where routes change direction and transition between shapes and sizes.
3. Branch: The branch condition solves scenarios where side branches are routed from existing runs.
4. Linear: The linear condition determines which catalog type and item are used for routing.