You’re loading wet clothes into the dryer and doing it quickly so you can get back to the kitchen now that you hear the pot of water you placed on the stovetop beginning to boil. You close the dryer door, adjust the heat setting, and press the start button. But wait. Instead of the dryer starting up and the drum turning, all you’re hearing is a humming noise. If you’re one of those do-it-yourselfers who can’t stand to leave a non-working appliance idle for long, you better turn off that stovetop burner. Tonight’s pasta dinner can wait; you need to determine if your dryer’s drive motor has failed!
What does a dryer drive motor do?
That humming noise you’re hearing when you press the dryer’s start button is a strong indicator that the drive motor is malfunctioning. In this article, we’ll present the steps Repair Clinic recommends you take to troubleshoot the problem. As always, it’s a good idea to familiarize yourself with exactly what a dryer drive motor does before you begin troubleshooting.
The drive motor rotates the drum
It doesn’t matter if you use a gas or an electric dryer to dry your clothes, towels, and linens, the unit’s drive motor has the same two functions. The first function is to rotate the drum to tumble the laundry so the load can dry evenly. The belt that is looped along the outside of the drum is also looped onto a drive pulley attached to one end of the motor’s drive shaft. As the motor drive shaft turns, this pulley drives the belt. A second pulley, known as an idler pulley, applies tension to the belt so it will properly grip the outside of the drum in order to rotate it.
The drive motor also spins the blower wheel
The drive motor’s second function is to spin a blower wheel. The blower wheel is attached to the opposite end of the motor shaft so when the motor is running, the drive shaft will rotate both the drive pulley and the blower wheel at the same time. The spinning blower wheel will circulate the heated air throughout the inside of the dryer drum as the laundry is being tumbled.
Dryer drive motor troubleshooting steps
Before you begin troubleshooting the dryer’s drive motor problem, confirm the appliance’s power cord is unplugged. You will also need to disassemble the dryer to reach the drive motor and blower wheel. This will usually require removing a top panel along with a front panel and, if applicable to the model, a bulkhead. You may also need to remove the drum for better access.
The first troubleshooting step is to inspect the blower wheel
Your first troubleshooting step is to inspect the blower wheel for an obstruction such as lint or a small article of clothing. The obstruction could be what’s preventing the blower wheel and the motor shaft from turning. Once you’ve confirmed there is no obstruction, try turning the blower wheel by hand. The blower wheel should turn freely. A blower wheel that does not turn freely is a strong indicator that the drive motor bearings have seized and the existing motor will need to be replaced with a new one.
The next step is to test the drive motor for electrical continuity
If the blower wheel does turn freely by hand, you can take the next step and use a multimeter to test the drive motor for electrical continuity – a continuous electrical path present in the part. This will help determine if the motor is defective or not:
1) If applicable, document the location of the wires connected to the motor, then disconnect those wires or the motor’s wire harness connector.
2) Using the appliance’s wiring diagram, determine where the motor’s start and run windings are.
3) Isolate the start and run windings, if possible, by detaching the wires.
4) Rotate the multimeter’s range selection dial to the lowest setting for ohms of resistance.
5) Contact the black meter lead to the motor protector terminal and the red meter lead to the start winding wire terminal.
6) If the meter display shows two to five ohms of resistance, the drive motor’s start winding has electrical continuity.
7) Keeping the black meter lead on the motor protector terminal, move the red meter lead to the run winding wire terminal to determine what the ohms of resistance are for the run winding.
8) If both windings show two to five ohms resistance, the motor has electrical continuity and should be functioning properly. If the display doesn’t change when testing either the start or run winding, the motor has no continuity and you’ll know it’s defective.
Test the motor’s thermoprotector for voltage input
You can also use the multimeter to test the motor’s thermoprotector to confirm the motor can receive the voltage it needs to run:
1) Disconnect the wires from the thermoprotector terminals.
2) Contact the black meter lead to one of the thermoprotector’s terminals and the red meter lead to the other terminal.
3) The multimeter display will indicate close to zero ohms of resistance if the thermoprotector has proper continuity.
If the multimeter indicates that the thermoprotector has no continuity, the entire motor will need to be replaced with a new one.
Additional repair guidance can be found at Repair Clinic
If you need help accessing the dryer’s drive motor, enter the full model number of the appliance in the “Videos & Articles” search bar on the Repair Clinic website. The Repair Clinic content library has the repair guidance you need to fix your dryer, including hundreds of dryer “Disassembly” and “Part Replacement” videos such as one which takes you through replacing a drive motor on a Whirlpool Alpha Electric Dryer (Model WED85HEFW0) or one that shows you how to install a new drive motor on a Frigidaire Washer/Dryer Combo Laundry Center (Model FFLE3900UW1). You’ll also find step-by-step guides, diagrams, and schematics to assist you in repairing all of your other major home appliances, lawn & garden equipment, and heating and cooling units.
When replacing a drive motor, or any other component on a dryer, Repair Clinic recommends using only genuine manufacturer parts. By installing genuine OEM dryer parts from manufacturers such as Bosch, Electrolux, GE, Kenmore, LG, Maytag, Samsung, Speed Queen, or Whirlpool, you’ll be extending the life of the appliance by using a part specifically designed to work with that particular model. To find the exact part you need, enter the full model number of your dryer in Repair Clinic’s search bar. The resulting list will be all the parts compatible with your model. From there, you can use the “Part Category” (example: “Motor”) and “Part Title” (example: “Drive Motor”) navigation filters to narrow the full list down to identify just the part you’re looking for.