Some lenses behave erratic meaning they may or may not make IR hot spots. It all depends on lens/camera combination, aperture setting, whether the filter is internal (in camera, over sensor), rear- or front-mounted over the lens; the filter type, and the general conditions under which IR shooting takes place. Plus of course the kind of post processing conducted on the RAW files later. Some zoom lenses, such as AFS 17-35/2.8, AFS 24-79/2.8, or AFS 17-55 (DX) are typical examples. Amongst the older Nikkors, the 25-50/4 or 28-45/4.5 comes to mind.
One simply has to try and make the best of the situation. Not stopping down too far often helps. Some lenses can cope with f/8, are doubtful at f/11, and hotspots badly at f/16 and beyond.