A dryer that tumbles clothes but blows cold air is one of the most common repair calls. The good news: in most cases, the fix is a $15-40 part and a 30-minute repair. Here are the 7 most common causes, in order of likelihood.
The thermal fuse is a one-time safety device that opens the circuit if the dryer overheats. Once it blows, it stays open. The dryer will tumble but never heat.
Location: On the exhaust duct or near the heating element housing.
Test: Disconnect power. Unplug the thermal fuse. Set multimeter to continuity. A good fuse reads 0 ohms. A blown fuse reads OL (open). Replace if open.
Fix: Replace the thermal fuse ($10-15). But find out WHY it blew — usually a blocked exhaust vent.
Important: Do NOT bypass the thermal fuse. It's a safety device. Clear the vent and replace the fuse.
The heating element burns out from thermal cycling. It's the most common wear part in a dryer.
Location: In the heating assembly at the back of the dryer (electric) or in the airflow path.
Test: Disconnect power. Unplug the element wires. Set multimeter to ohms (200 ohm range). Measure across the two terminals. A good element reads 10-30 ohms. An open circuit (OL) means the element is burned out.
Fix: Replace the heating element ($20-40). While you're in there, check the element housing for cracks and replace the heat-sensitive resistor if needed.
The high-limit thermostat (hi-limit) is a safety switch that cuts power to the heating element if the temperature gets too high. When it fails open, the element never gets power.
Location: On the heating element housing or in the airflow path.
Test: Disconnect power. Unplug the thermostat. Set multimeter to continuity. At room temperature, it should read 0 ohms (closed). If it reads OL, it's failed open.
Fix: Replace the high-limit thermostat ($10-20). Also check the low-limit thermostat at the same time.
The low-limit thermostat cycles the heating element on and off to maintain temperature. When it fails open, the element never gets power.
Location: On the heating element housing.
Test: Same as the high-limit. Should read 0 ohms at room temperature.
Fix: Replace the low-limit thermostat ($10-20).
The thermistor measures the temperature of the exhaust air and sends a signal to the control board. When it fails, the control board may not activate the heating element.
Location: On the exhaust duct or near the heating element.
Test: Disconnect power. Unplug the thermistor. Set multimeter to ohms. At room temperature (70F/21C), a typical 10k thermistor reads 20-25k ohms. Compare to the manufacturer's table.
Fix: Replace the thermistor ($10-25).
If the motor isn't spinning fast enough, the centrifugal switch may not close, cutting power to the heating circuit. Or the belt may be slipping, causing the drum to turn slowly.
Test: Listen for the motor running. Check the belt for wear, stretching, or breakage. Check the drum for obstructions.
Fix: Replace the belt ($15-30) or the motor ($80-250).
The control board sends power to the heating element via a relay. When the relay fails, the element never gets power.
Test: If all the above components test good, the problem is the control board. Listen for the relay clicking when the dryer enters the heat cycle.
Fix: Replace the control board ($80-200). This is the most expensive repair, so rule out the other 6 causes first.
For step-by-step repair procedures with safety warnings, see our Dryer Not Heating Repair Guide.
For component identification and test procedures, see our Component Reference.