Is it cheaper to use a window unit other 2 rooftops ?

bushnell wrote:
Would it be cheaper go with a window unit or just use the two roof top units already on unit?

Define cheaper?

Do you have the window unit or will you be buying? After buying a new unit any savings will disappear.

Are you trying to save electricity?

Keep in mind that window units are usually 5,000 to 8,000 BTU which is substantially smaller than the rooftop unit.

If two units have the same efficiency, a smaller unit running constantly will use less electric than a larger one running occasionally.

A smaller unit running constantly will also reduce humidity better than a large unit running occasionally.