I would be happy to help you out.
May I have the model # XXXXX your dryer?
I am going to say that it sounds like you have a plugged vent. Whether its on the outside of the dryer or the inside. If the air cannot escape the dryer, it will build up heat to quickly and shut the burner off. This is why clothes start to take forever to dry.
The best thing to check first with this type of problem are the vents. Start with the tube that the lint filter goes into. Remove the back of the dryer and pull the vent off where the blower wheel is. There are a series of screws around the cover. You will find that this is more than likely jammed up with all kinds of stuff.
If you have anymore questions, please feel free to ask.
You problem sounds like a venting issue. On this model dryer, the blockage tends to be where the lint filter goes into the dryer. Cleaning this with a lint brush will not get the area you need to clean.
Again, take the back off the dryer, remove the piece the lint filter slides into and clean that out. You will see what I mean when you get that off.
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