Register loose damaged missing Register screws often come loose allowing the register to dangle and endanger those below. Registers also often stick in an opened or closed position, or somewhere in between. Usually loose registers can be repaired with screws that are longer or larger than the existing ones. Often the existing ones are simply loose and can be tightened. Sticking registers can often be loosened with oil or the like, but let the oil sit on the joints for several days before trying to break them loose. Replacements for missing registers can usually be purchased at building supply outlets or at air conditioning supply dealers. Take the measurement of the opening with you when attempting to purchase a new one. Noisy registers can often be replaced with ones that let more air pass through thereby reducing the noise of restricted air movement. A sheet metal contractor or an air conditioning contractor may be consulted for additional opinions. It is likely simple solutions can be found for all the above problems as they are generally not complicated situations.