I have just change the heating eliment on my white knigt tumble dryer and now both sides of the eliment seem to be getting hot but the air coming from the vent is cold i'm not 100% sure if the wires are connected correctly as my piece of paper disappered that i wrote the connections on
looking at the machine from the front the left hand side should have 2 black wires the middle will have a red wire and the right will be blue. But if you elements are getting hot you mite have a blockage.