Knocking noise when the dryer is running

Knocking noise when the dryer is running No dryer can operate silently. The hum is caused by the rotation of the drum, the operation of the fan and other processes. Normally, the noise level of the machine should not exceed 70 dB, the figure will depend on the model of the device.

Acceptable sounds include a uniform hum during operation of the device. When exactly the dryer knocks is not considered normal. Let's figure out what can cause the rumble and what parts of the dryer will need to be checked.

Let's figure out the reasons for the “bad” sound

First you need to determine the nature of the knock. If it is a uniform, barely perceptible hum, then everything is fine with the machine. When the dryer knocks distinctly, and the process is accompanied by vibration of the housing, diagnostics should not be postponed.

In fact, your dryer can knock for a variety of reasons. We'll have to check every guess.

The washing machine is not level. If installed incorrectly, the dryer will knock, vibrate, and move out of place. That’s why it’s so important to level the housing before you start using the “home assistant.”
Overload When using a dryer, it is very important to comply with the manufacturer's maximum load weight. If the drum is designed for a maximum of 6 kg of laundry, you should not try to stuff more things into it. This will eventually lead to failure. And at the moment the dryer will knock loudly.
Imbalance. During the drying process, large items may clump together. The “ball” of laundry will jump inside the machine, hit the walls of the drum and knock. In this case, the solution to the problem will be to distribute the laundry evenly inside the dryer.
Foreign object inside the drum.Coins, keys, or hairpins forgotten in a pocket can easily end up in the machine and cause a knock. In this case, there is no need to worry - just take the loud items out of the dryer.
Object stuck between tub and drum. This case is the worst outcome of the situation described above. For example, a bra wire, bobby pin, or stud can easily fall even deeper and end up in the dryer tank.
Stretched drive belt. When the rubber band breaks, the dryer stops working and the drum stops rotating. If the strap stretches, the machine will continue the cycle, but will make loud, whistling sounds.
Damage to support rollers. This happens when the machine sits idle for a long time. Then the elements are deformed and become flat. The solution to the problem is to replace components.
Bearing wear. In such a situation, there is a strong knocking and grinding noise when the dryer operates. Especially when the drum rotates at maximum speed. To replace the bearing assembly, you will have to almost completely disassemble the dryer.

If you notice that your dryer drum is knocking, check the most basic things first. See if the “home assistant” is standing straight and if things are not out of alignment. Also make sure there is no foreign object inside causing noise.

Diagnostics of the dryer is carried out from simple to more complex.

You can also check the drive belt, and, if necessary, replace it yourself. The work does not require any special knowledge or skills. In the case of bearings and support rollers, it is better to seek help from a specialist.

Changing the belt yourself

This is one of the problems that is easy to deal with on your own, at home.The rubber band spins the dryer drum, allowing it to rotate. When the drive belt stretches, the operation of the mechanism is disrupted, and the dryer begins to knock and squeak.

To check the condition of the drive belt:

turn off the power to the dryer;
if the machine is connected to a sewer, unhook the drain hose;
move the dryer away from the wall;
remove the top cover of the CM housing by unscrewing the bolts securing it;
Unscrew the screws holding the side or rear wall (depending on the SM model), move the panel to the side.

Inspect the drive belt. Its stretching is noticeable to the naked eye. The elastic band will dangle and may also appear frayed. The solution to the problem is to replace the element.

The algorithm of actions will be as follows:

Unhook the shock-absorbing spring from the dryer motor;
remove the drive belt from the motor pulley;
remove the strap from the drum;
press on the drum, moving it slightly back (due to this, a small gap is formed between the front wall of the housing and the drum);
insert a new drive belt into the slot;
pull the elastic through the rollers, gently rotating the drum by hand;
slide the drive belt into its place (closer to the middle of the drum) and pull it onto the engine pulley;
Replace the shock absorber spring.

To check the operation of the drive mechanism, rotate the drum by hand. The container should rotate smoothly, without any extraneous noise or squeaking. If all is well, the dryer body is reassembled in the reverse order.

If you notice that your dryer is knocking, you don’t need to immediately call a technician. Often extraneous noise is caused by trivial reasons: overload, foreign object getting into the drum, imbalance. These problems can be easily fixed with your own hands.

You can also remove the foreign object from the dryer tank yourself and replace the drive belt. If the bearing assembly wears out, the machine will need to be completely disassembled, so it is better to contact a specialist.