There's a big difference between a dryer that doesn't heat up at all and one that just doesn't get hot enough to dry your clothes. In the first instance, the problem is usually a defective part, and things should be back to normal after you replace it. In the second instance, the problem is caused by restricted air flow, and you need to clear the lint filter and vents and take steps to prevent lint build-up. If you don't, you'll use more energy for drying than you need and the dryer may continue to malfunction. Worse, you may have a dryer fire.
If there is good airflow and the heater is working correctly, the thermal fuse should not burn out.
Thermal fuses burn out to prevent fires. All dryers have a high limit safety thermostat that cuts power to the element at a lower temperature than the thermal fuse burnout temperature. In addition, the dryer may have a thermometer and temperature control or a simple thermostat. So there are three temperature sensors in most dryers, and the thermal fuse is the last.
Dryer issues caused by venting, Longer drying times are an indication that airflow in your dryer vent is constricted. Inadequate airflow can be the result of a clog or obstruction in your dryer vent system. Excess dryer lint is a major fire hazard, it can cause your dryer to become damaged and reduces the efficiency of your dryer.
Lint behind dryer
It’s usually the vent not your dryer. An accumulation of excess lint behind your dryer can be the result of a clogged dryer vent. Since a clogged vent restricts airflow so that the air cannot move the lint to the outside of your home, it forces the lint into the area behind your dryer.
Dryer repeatedly stops, turns off during a cycle.
If your dryer stops repeatedly during a normal drying cycle, it is typically due to the dryer overheating. A dryer vent clogged with lint or other obstructions will force the dryer to work harder, causing the unit to overheat. The overheat shutoff is the dryer’s last attempt to prevent a fire.
There is excess lint left on your clothing.
Excess lint on clothing after a dry cycle is a sign of accumulation of lint in your dryer vent. A dryer vent cleaning clogged with lint is a fire hazard and an energy hog.
Clothes are very hot after a dry cycle.
The cause for this problem could be poor ventilation caused by a dryer vent clogged with lint, a bad vent connection, or a dryer vent joint that is not secure. These problems are not only a fire hazard, but also the overheating can damage the clothing as well as the dryer.
Clothes have a moldy smell after dry cycle.
When a dryer vent is clogged, the humidity removed from your wet clothes cannot exhaust through the vent so it back is out in the and collects in the duct creating the perfect growing conditions for mold and mildew. If you notice a moldy smell in your laundry room, have your dryer vent inspected immediately.
Water stains in the wall near the dryer appliance.
If the dryer duct runs behind the wall where you see water marks, it could be a clogged duct and condensation is leaking through the duct connections.
Complete list of dryer vent problems symptoms of a full of lint dryer vent is:
Dryer is getting warm or hot to the touch, the problem is NOT your clothes dryer.
Clothes taking longer to dry
Clothes still damp after a cycle
Appliance stops working during cycle
Laundry room gets hot or humid
You see lint around or behind the dryer,
lint screen gets full quickly
But your dryer is at a greater risk if:
Clothes are hot but still damp after one cycle.
If your dryer takes more than one cycle to dry
Dryer is hot to the touch
Laundry room is humid or warm when dryer is in use
Musty smell coming from dryer