My van is squealing after a recent harmonic balancer and accessory belts replacement.

Sometimes spring-loaded tensioner pulleys get rusted tight and don't properly tighten the belt once they have been moved to loosen the belt for some other service. Sometimes belt-driven items like power steering pumps and generators are mounted turned sideways just a little but that is enough to make the belt slide across the pulley as it goes around it. That will set up a squeal. The belt could also be worn in such a way that it doesn't match the grooves in the new harmonic balancer pulley exactly. A new belt will usually solve that.

Recheck the belt adjustment. For V-ribbed belts there is a tendency for tension to be under adjusted.

Thank you yes the power steering pulley is a little loose and the belt does not have an odd wear yet how do i adjust the tension i see there are some bolts i can slightly looses and put the power streering tighter?

Under the power steering pump there is a adjusting bolt that is held by a nut. Loosen the nut and turn the adjuster clockwise until the desired tension is achieved and retighten the locking nut.

Hope it is not the crank pulley that is not correctly torqued.