Dryer warm but not hot takes for ever to dry cloths

Either of these:
1. Air flow is blocked
2. Heating element is not working totally or not at all.
Check airflow for strong flow. If not. Unblock
check airflow for heating. If hot then heating element is working. If not hot, check heating element issue,ie, reset hi temp thermistor, check other thermistors, check heating element for continuity.
Report back what you find.

The thermostat which is a round 2 wire control on the blower box on the back of the dryer controls the heat on all dryers. always shut off power when checking any electrical appliance. Clothes dryers are wired with 2 voltages, The 240 volt supply is for the heating element only, while the 120 volt supply gives power to the timer and motor that spins the drum and powers any lights and switches. If the heating element is coming on, try replacing the thermostat. As always unplug the dryer first.

it could be the element burnt or restricted venttube or maybe even a burnt wire from the pigtail take the cover off where the pigtail goes into the dryer and see if one of the wires burnt

Clothes not drying? Thats it? Does the dryer turn on at all? Does it tumble the clothes but doesn't get warm? If it turns on and tumbles but takes a long time to dry, then your heating element is not working. There is a thermal fuse right before the heating element that will open up if the vent becomes clogged and its gets too hot. The thermal fuse is not resettable and will have to be replaced. If the thermal fuse is o.k. then your heating element could be burned out. These two items almost require an electrical meter to read continuity to check them. Make sure the dryer is unplugged before checking these items.

2 things are needed to dry clothes. 1 is good air flow. Check to make sure that the dryer vent is not clogged or partially clogged with lint. Also make sure there are no kinks in the vent hose. With the dryer running you should feel good air flow blowing out of the outside house vent. The 2nd thing a dryer needs heat. Check to see that the dryer feels warm to hot when you reach in to tough the clothes. It is possible that the heat element has partially failed. Another thing to investigate is how well the laundry machine is spinning out the water in the spin cycle. This spin cycle is used to get as much water out as possible prior to placing the clothes in the dryer. The wetter the clothes when they come out of the laundry, the longer it takes to dry them.

Getting hot when not started is a great concern.
I have a few ideas why, but this is a fire hazard and I would suggest unplugging and either getting help or replacing.
That said, there here are a few suggestions.
1) if the element is shorted to ground, it will get power to one side of the element and heat though ground. This, again, is serious.
2) if it heats forever and doesn't get warm enough to dry, this is another indication of an element that is not working up to power. Not getting 230 across the entire element and not getting hot enough to dry.
3) Many times when a dryer runs too long, the air flow if blocked by the vent being plugged or some plug withing the dryer itself.

Again, I am very concerned about this problem and suggest you not use it until it is repaired. If you want to check the element, it is fairly easy, but unit will need disassembled.

Mr Boo

Most common cause of this is a clogged venting going to the outside to test this remove the vent from the back of the dryer and run a load if it drys ok them you know you have a venting issue and will need to be cleaned out if not plz repost and we can look deeper into it

My dryer has been taking longer and longer to dry my clothes. Sometimes it takes multiple cycles before the clothes become dry. They seem to be getting warm, but are not drying as quickly as they use to.

umplug your vent and run dryer see if that will make a different when dryer your clothe if not may be gas coils

Either the heater element is breaking or is loose and getting only 110V instead of 240V.  First I would check the wall outlet with a voltmeter for 240V between Line1 and Line2.  Also check the connections and continuity for the heater element.