Mde4000ayw  It runs and hot air comes out the exhaust but clothes take for ever to dry. Help?

two possible problems
the air blower is not running properly
too many clothes being dried restricting air flow

This is the classic symptom of "poor air flow". Another symptom you didn't mention (but I bet is happening) is that the top of the dryer gets VERY hot. OK, don't move your dryer yet... get a flashlight and look behind there. See the flexible vent connecting the dryer to the wall? It must have SMOOTH, FLOWING turns. No crushing allowed. If it's crushed/pinched, you found the problem. It's "choking" off the air flow... not allowing the hot air to escape and containing all of it in the dryer cabinet. If this is the problem, pull the dryer away from the wall about 8" and make sure the vent isn't pinched off anymore. Leave your dryer this far out, it'll ensure that this doesn't happen again. If the flexible vent is OK, there is a blockage in your house's internal dryer duct work somewhere. Turn the dryer on and go outside to where the exhaust is. Check air flow. Check the exhaust vent for debris (I've seen birds build nests in the outside exhaust, incubates the eggs...but your clothes won't get dry!). If your dryer location and the exhaust location are quite a distance (20' or more) from each other, you should hire a professional to come out and thoroughly clean it out for you. In this case, you should have this done once a year as part of routine Home maintenance. To test and verify my solution to this, you can remove the dryer vent from the wall and cover the end of it with a pair of old pantie hose. Then run the dryer as usual (the pantie hose will act as a secondary lint trap). You'll see that the dryer will be happy again and the clothes will dry in no time at all.

If the dryer is getting hot (the heater element is working) but the clothes aren't drying, it suggests that there is insufficient air flow through the dryer. Remove the exhaust tube from the back of the dryer. With the tube removed and the dryer running, check for hot air (lots of it) flowing out the exhaust vent of the dryer. If there is good air flow, check the exhaust tube for lint build-up or a clog that is blocking the air from flowing through the tube. If there is no air coming out of the exhaust vent with the exhaust tube removed and the dryer running, it suggests that the problem is with the exhaust fan inside the dryer.

Check the exhaust vent when running and be sure there is a good flow of air. You may have to clean the exhaust pipes all the way through. Dryers require a good flow of air for proper operation.

Remove the back of the dryer and chek the lint filter area from the lint catching filter to the exhaust tube. There is a blockage in airflow even though you feel the air at the exhaust there still insn't enough air flow to allow the proper drying of the clothes. This symptom that you gave clothes being hot but not dry the only cause for this is improper air flow

Dave

sounds like an air flow problem meaning the dryer is not exhausting the hot air. Best way to check is to disconnect exhaust tubing from dryer and run a cycle. If the clothes dry normally the vent to the outside is plugged. Hope this helps

Check your dryer venting for obstruction.  Take the vent hose off and run the machine,  If it works with the venting disconnected, It is between your wall and the outside of the house.  If it still has the same problem it is somewhere in the exhaust.  If the dryer can't circulate air, nothing will dry.

Check to see that the lint filter and exhaust duct are clear all the way to the outlet. If the moist hot air is not being exhausted the clothes will not dry. If the vent path is clear and you are using auto-dry the sensor may be at fault.

An easy way to check dryer function is to check the airflow on the outside of your home at the exhaust the vent. While the dryer is running, and hot, put your hand near the outlet. The air coming out should be hot and forceful. If not, there is most likely an obstruction, and the whole airway should be cleaned. Keeping the airway clean and clear can dry clothes faster and save you money.

Another possibility is the blower,(fan) which can become encrusted with lint, preventing it from moving air. This is much less likely, but still a possibility.

A couple of possibilities to check. First, is the lint trap empty? If so, then the symptoms point to hot air bypassing the drum. Look for broken or misaligned plastic ducting inside the dryer itself. Check the exhaust air for moisture, as that is a better indicator than temperature. Don't forget that towels hold an enormous amount of water, & can be extremely long in drying, especially if not spun enough.