How to Diagnose and Fix Your Broken Dryer (A Comprehensive Troubleshooting Guide)

This is a complete diagnostic guide for an American household electric or gas dryer. I built it around the symptoms you’d actually describe over the phone — “won’t come on,” “won’t heat,” “won’t tumble,” “won’t shut off,” “makes a noise,” “element keeps glowing with the door open,” “runs for a few minutes then quits.” Walk through the section that matches your problem and you’ll narrow it down to the failed component without taking the whole machine apart.

I’m Chip Knowles. I run Harper & Knowles Washing Machine and Dryer Repair in Oakdale, Louisiana. Watch the full tutorial below, then read on for the symptom-by-symptom breakdown.

Watch the full tutorial

How to diagnose and fix your broken dryer

Before You Diagnose Your Broken Dryer

Unplug the dryer. Always. Don’t trust the off switch.
For gas dryers, shut off the gas valve behind the machine.
You’ll need a multimeter — Buy on Amazon . Set it to AC voltage for power checks, and to ohms (the Ω symbol) for continuity checks. Most of the diagnostic process is “does this component pass continuity, yes or no.”

Symptom 1: Dryer won’t come on at all

Work through this list in order. Stop when you find the failure.

1. Check the power at the wall. For electric dryers, you need 240V across the two outer terminals where the power cord connects, and 120V from the center (neutral) to each outer hot. With your multimeter on AC voltage, jump your leads across the two outside terminals first, then center-to-outside on each side. If you have 240 but only one side reads 120, one of your home’s two breakers for the dryer circuit is tripped — go to the breaker panel and check both. A 240V dryer is fed by two 120V breakers. Sometimes they’re tied together, sometimes they’re separate. Some houses also have a separate dryer breaker on the outside of the home.

For gas dryers, check that the wall outlet is delivering a clean 120V. Older homes sometimes have failing outlets.

2. Check the door switch. Open the door, close it firmly, and listen for the click. No click usually means a bad switch. To confirm, you’ll need to disassemble the top and run a continuity check on the switch terminals. GE, Samsung, and Whirlpool all use slightly different door switches but the test is the same.

3. Check the timer knob (GE / Hot Point dryers especially). A common GE failure: the plastic timer knob cracks at the D-slot and the customer is turning the shaft of the knob without turning the actual timer. Pull the knob off and look at where the D-slot bites into the plastic. If it’s cracked, the timer never actually advances out of the OFF position. The replacement knobs now come with a metal ring around the D-slot to prevent this.

4. Check the belt and idler pulley tension switch. Once you’ve ruled out external causes, pull the cabinet apart. If the drum spins freely with no resistance, the belt is broken. Many Whirlpool dryers also have an idler pulley tension switch that opens the circuit when the belt is broken or slack — test it for continuity by pushing the microswitch arm while reading across the two terminals.

5. Check the low-limit thermal fuse. Found on the blower side (not the element side). Long and white on Whirlpool/Maytag/Kenmore; round button-style on Samsung, LG, and some others. Run continuity across it — if it’s open, replace it. And find out why it blew, because the fuse is the symptom, not the cause (see the airflow guide for the usual culprits).

6. Check the start switch. Push-to-start switches on Whirlpool, turn-to-start on some GE models. Continuity should close when you press the button.

7. Check the timer points. Last resort for “won’t come on.” Pull the timer, take the back plate off, look at the internal points for burning or pitting. A burned set of points means the timer is done — replace it.

Symptom 2: Dryer runs but won’t heat (electric)

1. Verify both legs of 240V power. Same check as above. If only one 120V leg is feeding the dryer, the motor will run but the element won’t have the second leg of power. This is the #1 cause of “runs but doesn’t heat” — half the power got lost between the breaker panel and the dryer.

2. Inspect the element wires. Open the back of the dryer and look at the wires bolted to the heating element. I’ve seen them burned right off the terminal for no apparent reason — common on older Whirlpool-style machines.

3. Check the high-limit thermal fuse (one-time, found on the element shroud, usually rated around 309°F) for continuity. Open = blown, replace it. Like the low-limit fuse, find out why it blew or you’ll be replacing it again.

4. Check the high-limit thermostat (resettable, mounted on the element shroud, typically a 250°/80° unit — meaning it opens at 250°F and resets when it cools 80° back down). Continuity test across the two terminals.

5. Test the heating element. Two things to check: continuity end-to-end (open = broken element), and resistance from each element terminal to the frame (any continuity to frame = grounded element, replace it).

6. Check the cycling thermostat. Located on the blower next to the long thermal fuse on Whirlpool-style machines. This is the one that controls the dryer’s actual run temperature — it opens at a set temperature (commonly 155°F), cools 25° back down, and closes again. If it’s stuck closed, your dryer overheats and blows fuses. If it’s stuck open, the element never energizes. Test note: if your multimeter has an audible continuity beeper, the cycling thermostat’s internal coil sometimes won’t beep even when it’s good. Use the digital ohms reading instead.

7. Check the timer points (the set that controls the element circuit).

8. Last resort: motor switch. The motor has a centrifugal switch inside that only sends power to the element after the motor spins up to speed. If that switch fails, the element never gets power. Replacing the motor switch is rare but I’ve seen it.

Symptom 3: Dryer runs but won’t heat (gas)

Check in this order:

Low-limit thermal fuse (continuity). On a gas dryer, a blown low-limit fuse still lets the motor run but kills the ignition circuit — the drum turns and no flame.
Igniter — does it glow? Visual check.
Gas valve coils — test continuity on both coils. The two-terminal coil checks across the two posts. The three-terminal coil checks from the center to each outer terminal.
Flame sensor (electric eye) — continuity check.

Symptom 4: Drum won’t turn

Broken belt — lift the cabinet top and look for the belt sitting in the bottom of the machine.
Belt slipped off the drive pulley — lots of slack when you push down on the belt at the top of the drum.
Broken drive pulley — aluminum drive pulleys on older Whirlpool-style motors crack and break right at the nut. Inspect with a flashlight.
Failed idler pulley — if it’s intact and moves freely on its shaft, it’s probably fine. If the plastic wheel has worn a groove or seized, replace it.

Symptom 5: Dryer runs a few minutes then quits

This is usually one of two things, and both are good news for you:

Door latch is weak and slight vibration is letting the door pop open enough to break the door switch circuit. Replace the latch or the switch.
Motor is dying. The motor has an internal thermal cutoff that opens when it overheats — a failing motor will run a bit, hit the cutoff, quit, then run again once it cools down. Tell-tale sign: an electrical burning smell or a loud hum before the motor starts spinning. The thermal cutoff inside the motor isn’t replaceable on its own — replace the whole motor.

Symptom 6: Dryer won’t shut off

If the dryer keeps running well past the time the timer should have ended the cycle, the timer motor isn’t advancing. The timer motor is powered through the heating element circuit — so if the element isn’t drawing current (because the cycling thermostat opened, or the element is broken), the timer motor stops. Result: machine runs all day blowing cold air on dry clothes.

Mark the timer knob with a pencil and watch whether it advances. If it doesn’t, replace the timer.

Symptom 7: Element glows when the door is open

The heating element has either broken internally and grounded to the frame, or has shorted to ground. Whenever the timer is on a setting that energizes the element circuit, the grounded portion of the element will draw current straight to ground and glow — even with the motor off and the door open. This is a fire risk; hopefully the high-limit thermostat trips before something catches.

Check by running continuity from each element terminal to the frame. Any continuity = grounded element. Replace the element.

Symptom 8: Dryer makes a noise

Match the noise to the cause:

Squealing — something caught between the drum and the seals (screws, coins, rocks — I find them all), OR the belt rubbing against a seized idler pulley. Pull the front off and inspect.
Thumping — flat spot on a drum support roller. Whirlpool-style dryers have two rollers in the back; some Samsung models have four rollers (two front, two back). Replace any roller that’s flat, seized, or has lost its rubber surface.
Severe rattling near the motor or blower area — broken blower wheel or failed motor bearings. GE/Hot Point dryers are particularly prone to stripped blower wheels at the motor shaft.

A note on testing the cycling thermostat (and thermistors)

This one trips up techs all the time. The cycling thermostat in modern dryers has four terminals: two for the thermostat itself, and two for an internal coil that lets the control board cut off the heat sooner for low/medium temperature settings.

If you use your multimeter’s audible continuity feature, the coil portion sometimes won’t beep even when it’s perfectly good — there’s a diode in the circuit. Switch off the audible beeper and use the digital ohms display. You’ll see a reading that confirms the coil is intact.

Same thing with thermistors in newer dryers — they have a diode that defeats the audible mode. Always trust the digital reading over the beeper.

When to call us

If you’re in central Louisiana — Oakdale, Oberlin, Glenmora, Elizabeth, Pitkin, Pine Prairie — and you’d rather have someone diagnose it for you, give Harper & Knowles a call at (337) 831-6757. Most dryer service calls are same-week, often same-day.

If you’re outside our service area, hopefully this guide narrowed it down for you. Drop a comment on the Harper & Knowles YouTube channel with the symptom and any unusual details and I’ll do my best to point you in the right direction.