Diagnosis of Tumble Dryer Problems

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TUMBLE DRYER DIAGNOSIS

While you can always dry freshly washed laundry on a clothesline or a drying rack, a gas or electric clothes dryer has become a staple in most homes. When it stops working correctly, here are several common dryer problems that you may be able to solve yourself without calling a repair technician.

 

Problem: Dryer Won’t Heat

Solutions:

If you have a gas dryer, check the supply line valve. It must be fully open to operate properly.

Electric dryers use two household fuses or circuit breakers. The drum can still turn if just one fuse is blown, but there will be no heat. You may need to replace both fuses or reset both circuit breakers.

If the dryer’s thermal fuse has blown due to a power surge or other mechanical problem, the dryer won’t heat. These fuses are easy and inexpensive to replace. Locate your user or repair manual, and you can find replacement parts at online retailers.

Problem: Dryer Cuts off After a Short Period

Solution:

When a dryer shuts off abruptly after “working perfectly,” it is usually a problem with either the thermostat, the thermal resistor, or the thermal fuse that turns off the dryer to prevent overheating. You can check each of these parts with a voltage meter to determine if they are working properly or if they need to be replaced.

 

Problem: Dryer Making Unusual Noise

Solutions:

If you hear a thumping sound or see vibrations, the dryer may not be level. Each leg of the dryer can be adjusted and it should be leveled front to back and side to side.

Check for small items caught in the dryer drum. Coins, buttons, or paper clips can get caught between the drum and the front or rear of the dryer. Use a flashlight to inspect the drum and remove any objects. Always check and empty pockets before loading a washer or dryer.

If you hear loud thumping, the clothing may be knotted or balled up. You may not be loading the dryer correctly. Remove the knotted items and give them a shake before reloading to complete the drying cycle.

If you have a gas dryer and hear a clicking sound, this is normal. It is the gas valve opening and closing.

Problem: Dryer Won’t Start

Solutions:

The door latch may not be engaging. Check the latch for lint and clean it completely so that the door closes properly. When the lint is removed, use a bit of rubbing alcohol on a cotton swab to clean metal contact areas.

Check the power supply, including fuses and circuit breakers. When replacing a fuse, be sure to use a time-delay fuse.

Check the dryer’s internal thermal fuse. If it is blown, the dryer will not start.

If you have a push start knob, it may not be engaging correctly. Remove the knob and clean behind it, removing any dirt and lint.

Problem: Clothes Take Forever to Dry

Solutions:

Clean the lint filter. A filter loaded with lint reduces the airflow necessary for quick drying. You can recycle the lint for crafts.

Clean the outside exhaust vent. If the outside vent is not opening and closing properly, moisture is trapped inside the dryer drum. Run the dryer for five or 10 minutes. Go outside and hold your hand under the outside exhaust hood to check air movement. If you do not feel air coming from the vent, it is blocked with lint and must be cleaned thoroughly. Remove any snow or leaves that may be blocking the vent. Also, make sure the dryer vent duct is clean.

Check the dryer vent exhaust pipe. Be sure it is connected properly and has no kinks. If you are using a flexible hose, replace it with a rigid system.

Reduce the size of each load. An overcrowded dryer does not allow clothes to tumble freely and receive heat evenly.

Be sure the dryer is in a room that is above 45 F. A dryer cannot work efficiently in a room that is too cold.

Check the air circulation around the dryer. If your dryer is in a closet, there must be ventilation openings at the top and bottom of the door. The front of the dryer requires a minimum of one inch of airspace and the back should have at least five inches.

Do not allow fabric softener dryer sheets to block the airflow into the lint trap or grill. Never use more than one sheet per load.

Problem: Clothes Are Covered With Lint

Solution:

Clean the lint screen. If the screen is full and cannot hold any more lint, then the lint is going to stay on your clothes.

 

Problem: Clothes Aren’t Dry After Automatic Timed Cycle

The load may not be connecting with the moisture sensor strips because there are not enough clothes in the drum or the dryer is not level. Small loads should be dried on timed dry rather than automatic dry.

Clean the moisture sensor strips. The moisture sensors are usually two metal strips located inside the front edge of the dryer drum. If they become coated with residue from fabric softener sheets, they won’t work properly. Clean them with a cotton ball and rubbing alcohol.

 

COMMON DRYER PROBLEMS AND HOW TO FIX THEM

This list of common dryer problems can help you troubleshoot and find the reason your dryer isn’t working as it should. Of course, there may be other issues, but these are the most common problems. Some are simple fixes that won’t even require a screw driver and other solutions may fall outside of your comfort level and you may choose to hire a professional to do the work. Whatever you decide always put safety first and removes the power source to the dryer before troubleshooting or attempting repairs. If you need to purchase new parts, be sure to know the manufacturer and model number of your dryer. Although some parts may be universal, there’s nothing more frustrating than having the right part for the wrong model.

 

 Common Dryer Problems

  • Tumble Dryer is Won’t Turn On
  • Noisy Tumble Dryer
  • Wrinkled Clothes from Tumble Dryer
  • Does Not Tumble
  • No Heat
  • Tumble Dryer Takes Too Long for Clothes to Dry
  • Dryer Too Hot

We highly recommend taking detailed notes or photos as you remove panels, parts and especially wiring. What may seem obvious while you are removing the parts may seem less clear when the time comes to replace the pieces. The time you spend upfront will be saved in the end and you’ll likely be far less frustrated. Beyond a screw driver and a few other common tools you likely have in your tool box, you’ll need a Multimeter to perform many of the troubleshooting tasks. If you don’t already have one, they are an inexpensive and handy device that you’ll find yourself using whenever you have an issue with an appliance.

 

#1 – Dryer Won’t Turn On

If your dryer won’t start there’s a number of different things that could be causing the problem. You’ll likely need to do a little troubleshooting to identify the cause. But as simple as it may sound, first check your control settings to ensure that all buttons are fully depressed and that the settings are correct. Also, check that the start button was either pressed or turned enough to activate the dryer.

  • Power

Check the power supply first to ensure that electricity is reaching your dryer. Use your multimeter to check the voltage at the outlet. If power is not flowing to your dryer, check your home’s electrical panel to see if any breakers may have been tripped.

If the breakers haven’t been tripped, it’s possible that the outlet needs to be replaced. If this is your problem it’s probably a good idea to contact an electrician unless you are comfortable working with electricity.

If the breakers haven’t been tripped, it’s possible that the outlet needs to be replaced. If this is your problem it’s probably a good idea to contact an electrician unless you are comfortable working with electricity.

If your outlet checked out with the multimeter and your dryer is getting electricity, the problem could be the power cord. Dryer power cords are prone to fraying due to movement and age.

  • Terminal Block

The power will need to be ON for this test, so be extremely careful. If you are uncomfortable working with electricity, this may not be something you will want to undertake and you should call an experienced repairman. Remove the power cord access panel and use your multimeter to check the voltage at the terminal block.  Replace the terminal block if it is faulty. Unplug the dryer and unscrew the mounting screws to disconnect power wires from the terminal block. Use a flathead screwdriver to remove the terminal block from the casing. Install a new terminal block.

  • Door Switch

The door switch will keep the dryer from starting if the door is open. Frequently lint or other debris collects around the door gasket or switch. This build-up can prevent the door from completely closing and engaging the switch. If this is your problem, it’s an easy fix and something you can clean regularly to prevent future occurrences.

If you suspect the door switch is faulty, you may need to open the cabinet in order to troubleshoot and replace the switch depending on your model and manufacturer.

 

  • Thermostat

There are a number of different thermostats in your dryer with the single job of regulating the internal temperature. Which thermostat being used is determined by which drying cycle is selected. The cycling thermostat is generally located in the air flow path as it leave the drum. It is frequently inside the venting/exhaust system or on the blower wheel housing. A thermostat is about 1-1/2″ long and is oval shaped. Be sure to label the 2 wires when you remove them so you can reconnect them in the same way.  When the thermostat is at room temperature test with your multimeter set to RX1 and touch the probes to each terminal. If the thermostat is still in working order it will give a reading of zero since we are testing for continuity. If you receive anything other than a zero reading it will need to be replaced.

 

  • Start Switch

If the start switch is faulty your dryer obviously won’t start. To troubleshoot this problem remove the knob from the start switches and opens the control panel. Set your multimeter to RX1 and remove the leads to the switch. Clip the probes to the terminals of the switch. You should have a reading of infinity. Next press the start button and check the reading. It should now read zero. The start switch is faulty and will need to be replaced if this was not the case.

  • Thermal Fuse

Some dryers are designed with a thermal fuse that is within the exhaust duct in the rear panel. Once the thermal fuse is tripped the dryer will not operate (or it may simply stop heating). There is not a way to reset this fuse so it will need to be replaced if it tripped.

 

#2 – Noisy Dryer

There are many moving parts on a dryer and as they show signs of wear, they often begin to make noise. There’s squeaking, squealing, humming and even thumping. Many of the noises a dryer makes are a sign that something in your dryer needs attention. Read our extensive article on troubleshooting a noisy clothes dryer for a more comprehensive list. Below are a few of the more common issues:

  • Glides

Dryers often have plastic glides located in the front end of the drum. Over time, these glides show signs of wear and need to be replaced.

  • Blower Wheel

Although problems with the blower wheel can frequently require the part to be replaced, sometimes the fix can be as simple as cleaning out the blower. Often lint or other objects find there way into the blower wheel.

  • Drum Support Roller

Drum support rollers are used to support the drum. When they show signs of wear they can become very noisy. If yours needs to be replaced, be sure to replace all of the support rollers as they tend to wear evenly.

  • Belt

The main belt wraps around the drum and causes it to turn. As it wears out the belt will begin to make a thumping sound against the drum.

 

 

#3 – Wrinkled Clothes

If you find that your clothes are wrinkled after using your dryer, there are a couple things that may be the cause.  All of which are easy to fix and won’t even require you to use a screw driver!

Possible Cause:

  • Clothes not promptly removed from the dryer.
  • No fabric softener.
  • Too large or too small of load.
  • Incorrect water level.
  • Water is the wrong temperature (too hot) for the clothing.
  • Laundry not properly sorted.
  • Incorrect wash and dry cycles.

Solution:

Promptly remove clothing from the dryer and either fold or hang immediately.

The permanent press cycle will help reduce wrinkling by having a cool down cycle before it finishes. Don’t dry multiple loads at the same time. This will put too many clothes in the dryer at the same time. Don’t combine heavy and light clothing items together.

 

#4 – DOES NOT TUMBLE

Although there are a number of reasons the dryer’s drum won’t tumble, the most common cause is a defective belt, particularly if the motor is running.

  • Belt

When the dryer’s belt is worn or broken it won’t be able to turn the drum. You’ll need to replace the belt to get your dryer working again. Be sure you purchase the correct belt for your model. Then place the belt on the drum where to old belt had been and wind it onto the idler pulley and the motor pulley.

If the belt isn’t broken or worn, check that it’s in place on the drum and is properly fed thru the pulley configuration. The problem may be as simple as the belt being out of place.

If you need to replace your dryer’s belt, it’s a best practice to also install a new idler pulley at the same time. As the idler pulley wears out, it places unnecessary stress on the belt which shortens it’s service life. The original problem may not have been the belt, but rather the idler pulley. Failure to change the idler pulley may mean you end up replacing your new belt much sooner than you expected.

  • Drum Support Rollers

The dryer drum sits on top of drum support rollers and over time the rollers become worn and need to be replaced. Although this isn’t too difficult of a repair, you will need to remove the drum in order to reach the rollers.

  • Seized Motor or Support Parts

If the belt or idler pulley is the issue the motor should be running. However, when the dryer is on and you hear a buzzing or no sound at all there’s a good chance that your motor has seized. It’s possible that you’ll be able to replace the motor’s start capacitor, but don’t be surprised if you need a new motor!

  • How to Test for a Seized Motor (and other Part Issues):​

First, remove the belt and inspect the blower fan housing for blockages.​

Then, hand turn the motor shaft. If it doesn’t turn or it’s extremely difficult, there’s a good chance it is has seized and you’ll need a new motor.

If the motor turns with ease, turn ON the motor and allow it to run for a few seconds before installing a new belt. If the motor appears to run fine, the problem may be with the drum rollers or idler pulley. Next, rotate the drum by hand. If it’s difficult to turn, the problem is most likely the idler pulley, drum rollers or drum glides.

You can test each of these parts or simply replace them all since you have the dryer open.

 

#5 – No Heat

If your dryer isn’t producing any heat but it’s tumbling, there’s a couple of issues that could cause this problem. However, look for the obvious first by checking your dryer’s settings. Be sure that you have the appropriate settings for the clothes that you are drying. The fabric temperature and timer selections are all key to the performance of your dryer.

  • Thermal Fuse

Many dryers have a safety feature called a thermal fuse which protects the dryer from over-heating. The thermal fuse is generally in a white plastic housing and it’s located in the exhaust duct in the back panel of the dryer. The thermal fuse will “trip” and prevent your dryer from working if it gets too hot. There’s not a way to reset the fuse, so if this is your problem you’ll need to replace the thermal fuse with a new one. Best Practice: Inspect your dryer’s vents for lint build-up. It’s not uncommon for the thermal fuse to blow due to trapped heat within the vents. If this was the reason your fuse blew, it will likely happen again if not cleaned.

  • Heating Element (Coils)

A heating element is a coil made from nichrome (nickel-chrome alloy). They can be found behind the back panel of the dryer. Look for broken or burned areas by visually inspecting the heating element. Use a multimeter to check for continuity. Set the multimeter to RX and press the probes to the terminals of the element (remove the leads from the element first). The element is defective and needs to be replaced if you receive a reading of zero.

  • Temperature Switch

Access the temperature switch by removing the knob to the switch and opening the control panel. Set your multimeter to RX1 and remove the leads before touching the probes to the switch’s terminals. You should see a reading of zero or infinity. Next, test again after turning the switch. The reading should change. If in the first test your result was zero, you should see infinity. If you saw infinity the first time, you should see zero. With any other results you’ll need to replace the switch.

  • Thermostat

The thermostat is located in the back panel of the dryer. Set the multimeter to RX1 and remove one lead from the two outside terminals on the thermostat. Press the probes to the terminals. You should see a reading of zero if the thermostat needs to be replaced.

  • Timer

The timer is located in the control panel. Set your multimeter to RX100 and remove the leads from the timer motor. Clip the probes to the leads, if you receive a reading of infinity you’ll need to replace the timer motor.

  • Power Cord

Electric dryers draw a lot of power to operate. They should always be plugged directly into an outlet . . . never use an extension cord. Unplug the dryer and check the plug and cord for broken connections, burns or scorching. If there is a broken connection it’s possible that the dryer will continue to operate, but it won’t be able to deliver heat.

 

  • Ignitor (Gas Dryers)

If your dryer is powered by gas, check to see if the ignitor is cycling. If it is, yet the burner is NOT engaging, then you may have defective electrical coils in the gas valve. The electrical coils have wires coming from the top of a black cylinder and they are located near the burner valve assembly. The coils will open and supply gas to the burner when supplied with power.

Another thing to check is to visually see if your ignitor glows. If it doesn’t, look for a yellowish or white discoloration. There may also be a break in the ignitor.

Replace the ignitor if you notice a visible problem. If you don’t see anything obvious such as a burnt area or a break, check for continuity.

The issue could also be originating from somewhere else in the burner system or the control area.

  • Burner (Gas Dryers)

Check the flame. If the burner flame is burning clean and blue it’s functioning properly.

#6 – Takes Too Long for Clothes to Dry

If you notice your clothes are taking forever to dry, the problem may be simpler than you think!

  • Lint

It might surprise you that this annoying problem can be fixed by simply cleaning your lint filter. A dryer’s lint filter is designed to catch the lint and allow the air to flow. However, if you don’t clean it in a timely manner, it will force your dryer to work harder than necessary.

The air won’t be able to flow freely and it will not only take longer to dry your clothes, but it will often leave little specks of lint on your clean clothes. There can also be serious consequences since it could even cause a fire!

#7 – Too Hot

If you suspect your dryer is getting too hot it’s critical that you troubleshoot and resolve the problem as soon as possible. When a dryer experiences high operating temperatures it can become a very dangerous situation. Be sure to keep your personal safety a priority and be aware that the parts within the dryer may need to cool before handling as they may be extremely hot.

  • Thermostat

Check your thermostat by following the instructions listed above under “No Heat”.

  • Heating Element (Coils)

The instructions under “No Heat” for testing your heating elements are listed above.

  • Vent

Remove and clean the lint trap. If you have excessive lint build-up it could create a problem. It’s a good idea to clean the lint trap with every load, or at least every several loads.

Check the vent that runs from the dryer to the outside of the house. When this vent is obstructed you run the risk of your dryer overheating, but also a build-up of carbon monoxide. Once cleaned you should check it periodically to ensure that the problem has been resolved and it doesn’t clog again.