My dryer heats to dry clothes intermittently. Some days it works other days it drys 2 loads then won't heat up to dry after that. The dryer tumbles but no heat. My husband took apart the dryer and thoroughly vacumed all the lint out so that is not the problem.
Any thoughts

My dryer heats to dry clothes intermittently. Some days it works other days it drys 2 loads then won't heat up to dry after that. The dryer tumbles but no heat. My husband took apart the dryer and throughly vacumed all the lint out so that is not the problem.
Any thoughts
Verify the exit outside... sometimes birds can get it and lay their nests and this can compromise the ventillation... which is your problem, a ventilation problem. Also, how long is the hose that goes to the outside? Sometimes when it's too long and has many "elbows" that could be a problem too. To test, detach the part of the hose that is in the wall, try drying something heavy like jeans or towels on the timed drying selection. Make sure the hose is pointed towards the window so the air can ventillate outside or else your room will get all humid. If it works, then you know that the problem is with the ventillation. Good luck

My dryer vents out the side wall of the house so bird nests are not an issue for me. I don't have a window in this room so doing that test would be problematic. There are only two elbows at most.

Each elbow is worth about 10 feet extra... still... check the exit, make sure it is free of lint or any obstacles. Oooooor you can contact a tech or the manufacturer for technical advice.