How do you change a fan belt on a t reg transit van?

To change the fan belt on a T-reg Transit van, first ensure the engine is off and cool. Remove any covers obstructing access to the belt, then loosen the tensioner using a wrench to relieve tension on the belt. Carefully slide the old belt off the pulleys, noting the routing, and then install the new belt in the same configuration. Finally, adjust the tensioner back to apply proper tension to the new belt before reassembling any covers.