Clothes are not getting dried.

Check your dryer ducting.  If you have not cleaned your dryer ducting recently, it may be time to do so.  In order for a dryer to work correctly, it needs proper air flow.  A lot of people don't realize that just seeing the heating element glowing and the air blower fan running isn't enough to get your clothes dry.  If the dryer does not have a proper exhaust the air has no where to go.  All that air that is normally exhausted out of the dryer vent carries all the moisture from your clothes with it.  If the exhaust is clogged, all that moisture stays in the dryer and the dryer works harder to try to heat.  Your clothes stay wet and, eventually, your thermal cut-out and/or heating element will blow.  You could also have a clog somewhere inside the air baffle in the dryer.  This is where the exhaust fan is.  Lint can get trapped in this area clog up your dryer.  Here's a simple test you can perform:

1. Remove the exhaust ducting from the back of the dryer and dry one load in this manner, letting the dryer exhaust freely into your laundry room or garage.  Feel the air leaving the exhaust port on the back of the dryer.  The air should eventually heat up and be rather forceful.  If your clothes dry faster, then you know you have a clog somewhere in the ducting.  You will need to trace it all the way to where it leaves your home at the exhaust vent outside.  If it is run in a crawl space, make sure it is suspened from the rafters and not on the ground.  Leaving it on the ground makes it susceptable to rodents wanting to chew through to get inside your dryer.  Dryers provide a great source of warmth and bedding material (lint) and mice love them.  Also ensure thre are no sags in the line that will create areas for lint to collect.  If you find that your clothes are drying better, take care of the problem immediately.  Running a dryer for extended periods of time exhausting in your home can add unwanted humidity, dust and potential mildew.

2.  If your dryer still is not drying sufficiently, or you have very weak air flow coming out of the rear exhaust port.  You will need to remove the air baffle housing and check for clogs.  I experienced a home where a dryer would not heat, but the ducting was clear all the way to the exterior vent.  The heating element was also heating properly.  When I removed the ducting, however, there was barely any air coming out of the dryer.  When I inspected the air baffle housing I found a mouse nest as big as a shoe box and compacted to the point that I had to disassemble the unit to get it out.  You will find that MOST insufficient drying problems are directly related to the cleanliness of your dryer interior and your dryer ducting.  Not to mention, the potential for house fires if you do not maintain a dryer properly.  I have also found situations where lint became so backed up in a dryer that there was evidence of multiple fires inside the dryer.  Take the time to double check your dryer venting and replace those old plastic worn out vent hoses with new semi-rigid metal hoses.  They resist crimping and crushing and will not clog as easily.

NOTE: It is normal for the heating element to cycle on and off.  This is actually a symptom of a "healthy drying cycle".

I hope this information is helpful to you.  If you find no obvious signs of clogs or obstructions, let me know.  You may have something else causing your problem.