If your clothes dryer turns off too soon, or shuts down after running for a short while before your load is fully dried, check the following parts: dryer filter, venting, moisture sensor, high limit thermostat, blower wheel and the motor.
The first thing to check is to make sure that the dryer filter and venting is free from lint-build up. Lint buildup can restrict the air flow from your dryer, causing the high limit switch to cut out and the sensors to operate improperly. Check your lint filter and clean any lint from it.
Over time, residue from dryer sheets can coat the dryer filter, which can cause an increase in drying times and other problems. Try running the filter under water and if the water beads up instead of passing through the filter, then you know you have residue lingering on your filter. Run your filter under some hot water and use a soft toothbrush to remove any residue.
Check the dryer venting and make sure that it’s free from lint build up as well. Lint accumulation inside dryer venting can lead to a fire and also makes your dryer work harder and less energy efficient . Clean the dryer venting easily by using a dryer vent cleaning brush.
Clean the inside of the dryer by removing the outer casing and panels to vacuum up any lint of dust inside the dryer, especially any lint covering or surrounding the motor. A Refrigerator and Crevice Cleaning Tool Vacuum Attachment can easily reach underneath the dryer drum and into all the crevices inside the dryer. This same attachment can be used to clean underneath refrigerators and other appliances, so it’s a good multi-purpose cleaning tool.
The moisture sensors inside your dryer can become dirty or defective over time. Try locating the moisture sensor bars and cleaning them using a cotton ball and rubbing alcohol. If cleaning them does not work, consider replacing that part.
The high-limit thermostat monitors the air temperature inside the dryer drum, exhaust vent and the incoming air supply. If the dryer gets too hot, this safety device turns off the heating element. Over time, this part can become defective. Locate and test this part for continuity by removing the wires from the thermostat terminals. Replace if necessary.
The blower wheel moves air from the heating element to the dryer drum. If this part is damaged, air will not circulate through the dryer properly and the dryer might be overheating and switching off. Take the dryer apart and make sure there are no objects obstructing the blower wheel from functioning. This part may also need to be replaced.
The motor might be overheating and turning off on its own. It might be overheating due to excessive lint build-up surrounding the motor or restricted air flow caused by a faulty blower wheel or clogged dryer ducts. If the dryer venting is clean and the blower wheel is functioning properly, then the motor itself is faulty and will need to be replaced.