Applicable Systems
Serie
Symptoms
The dryer drum does not rotate. The motor hums but does not start, or it starts and then stops with a burning smell.
Possible Causes
- Drum belt broken or slipped off the pulley, preventing drum rotation
- Motor start capacitor failed, preventing the motor from reaching running speed
- Motor seized from bearing failure or lint buildup around the motor
- Drum support rollers seized, causing excessive load on the motor
Troubleshooting Steps
- Step 1: Open the dryer and inspect the drum belt for breakage
Replace the belt if broken; check the idler pulley for free rotation - Step 2: If the motor hums but does not start, test the start capacitor
Replace if the capacitance is below 90% of the rated value - Step 3: Rotate the drum by hand to check for binding
If the drum does not turn freely, inspect the support rollers and glides - Step 4: If the motor is seized, replace it with an OEM motor
Clean the motor housing area of lint to prevent recurrence
How to Reset
Reset: After replacing the faulty component, the dryer operates normally. No reset is required.
Common Replacement Parts
- Drum belt: Serpentine, 1800-2000mm length (Match to dryer model)
- Motor start capacitor: 5-10 microfarad, 250V AC (Match to motor rating)
- Drum support rollers: Pair, nylon with steel bearing (Replace both rollers)
Frequently Asked Questions
- Q: How long do dryer belts last?
Typically 5-10 years. Inspect annually for cracks or fraying. Replace proactively if the belt shows wear.
- Q: How do I know if the capacitor is bad?
The motor hums but does not reach speed. Test with a multimeter on the capacitance range; replace if below 90% rated.
- Q: What causes drum binding?
Worn support rollers, seized idler pulley, or foreign objects between the drum and the housing. Inspect the entire drive path.
Source: OEM Service Manual
Category: Air Dryer