yes, if the paper feels warm after sitting in the tray for half an hour then you will more than likely have tray heaters.
In the tray adjust set the air assit to maximum. On the left hand side of the tray there is a blue thumb screw, loosen this push it to one side then tighten again. Put one sheet of the paper you are trying to feed in the tray. Push the tray in, wait for it to elevate and pull it out. The deck should have stayed at the top. There should be a 1/2mm gap between your sheet and the paper guides. Adjust to this and loosen the thumb screw again and move it back to the orignal postion.
Try and feed a run again. If it continues to jam pull the tray out and have a look on the left hand side by the feed tyres there is a pressure adjustment pin. Move this to each extreme and see if this works.
If it still jam's take the paper out and put it on a desk or platen glass, how flat is it? If it has quite a bow in it I would say you will need a modified guide plate as it has a bevel to guide bowed stocks.
