Dryer quit heating. Tested thermal cut-off, thermastats, element, cleaned the dryer and made sure air flow was good. Thermal cut- off was bad replaced it and the dryer heated for 15-20 minutes and quit thermal cut-off was bad agian.now what?
ANSWER Hello Billy,
The thermal fuse is just that.....Thermal. This means that it is opened by temperature. Logically thinking, if the unit cannot get rid of the heat it produces, the thermal cutout will open to prevent a fire. If the thermal fuse continues to open, this means that there is too much back pressure from the exhaust duct. The only way to correct the situation is to correct the duct. I know you said you had checked it, but if it is flexible, this may be the only issue. Check the exhaust for crimps or clogs as this is the most probable cause and the most denied by customers. Remember the duct should be as short and straight as possible while being a full 4 inches for proper air flow even in the turns. Flexible ducting is insufficient as it has the ridges through the full length which slows the air flow. Plastic PVC piping is insufficient as the interior diameter is only 3 1/2 inches. The only ducting recommended by all of the manufacturers is the 4 inch aluminum dryer exhaust duct. For a 90° angle, they make the elbows in the aluminum and you should always duct tape the sections together as screws will catch lint and clog the new duct.
The dryer drum rides on seals made of felt. Since they are made of felt, they cannot hold pressure. If the unit has a ducting issue, it will build back pressure and blow past the felt seals and back into the cabinet with the thermal fuse.
Answered by AppliancePartsPros.com | Wednesday, August 29, 2012