Dryer Not Heating — Step-by-Step Diagnostic Guide

Q: Why is my dryer not heating?

A dryer that tumbles but produces no heat is almost always one of four component failures: a blown thermal fuse (most common on electric dryers), a failed heating element, a failed gas igniter or flame sensor (gas dryers), or a cycling thermostat that has failed open. A clogged exhaust vent is the root cause that triggers roughly half of all thermal-fuse failures — the fuse trips to prevent overheating when the duct is restricted. Start by confirming the symptom pattern (Step 1), then walk the four-component check in order: thermal fuse → heating element → gas igniter/flame sensor → cycling thermostat/thermistor. Clear the exhaust vent before installing any replacement part or the new part will fail again.

Q: How do I test a dryer thermal fuse?

Unplug the dryer and pull the back panel. The thermal fuse is a small white or silver rectangular component mounted on the exhaust duct, just upstream of the blower outlet — typically with two wire leads and two screws. Pull the leads off the terminals, set a multimeter to continuity (or resistance), and touch one probe to each terminal. A working fuse reads 0 Ohms (or beeps in continuity mode). A blown fuse reads OL — open circuit. If it's blown, replace it with a manufacturer-specific fuse ($5–20) — but clear the exhaust vent first. A fuse that blows without a clogged vent often points to a failed cycling thermostat, restricted airflow from a kinked flex duct, or a drum that's being overloaded.

Q: Can a clogged dryer vent stop the dryer from heating?

Yes — and it almost always does, eventually. A clogged exhaust vent is the root cause of the majority of thermal-fuse failures on electric dryers. When the duct is packed with lint, hot moist air can't escape the drum. Heat builds inside the cabinet, the thermal fuse trips to prevent a fire, and the dryer stops producing heat. The vent should be cleaned every 12 months as maintenance. Disconnect the flex duct at the back, run the dryer for 30 seconds, and confirm strong warm airflow at the dryer's exhaust port — weak or no airflow is the symptom. Use a $20–40 brush kit to clear the duct run, and check the exterior vent cap. The U.S. Fire Administration attributes roughly 2,900 dryer fires per year to restricted exhaust vents — treat this as a fire-safety issue, not just a convenience fix.

Q: What does it cost to fix a gas dryer that's not heating?

Gas dryer no-heat repairs are dominated by three components: a glow-bar igniter ($15–40 in parts, 30–45 minutes DIY), a gas valve solenoid coil kit ($10–30, 20–30 minutes DIY), and a radiant flame sensor ($10–25, 20 minutes DIY). If the problem is actually a tripped thermal fuse downstream of the burner — not the burner itself — the fuse runs $5–20 in parts. With a professional service call, expect $130–200 for most gas-dryer heating repairs including parts and labor. Before calling a tech, run the dryer briefly, smell for gas, and verify the gas supply valve is open. If the dryer runs but never makes an ignition sound, the igniter is the leading suspect.

Q: How do I tell if my dryer is electric or gas?

Look behind the dryer. An electric dryer has a thick 240V power cord on a dedicated 30-amp breaker (a heavy 3- or 4-prong plug) and a flexible 4-inch metal exhaust duct terminating outside. A gas dryer has a standard 120V plug (like any household appliance) plus a 1/2-inch flexible gas supply line running to the back of the unit, plus the same 4-inch exhaust duct. If you see only the power cord and an exhaust duct, it's electric. If you see a power cord, an exhaust duct, and a thin gas line with a manual shutoff valve, it's gas. Gas dryers also have a small gas control valve and burner assembly visible behind the lower access panel — electric dryers do not. The diagnostic steps in this guide split between the two: the thermal fuse / heating element / thermistor path applies to electric dryers; the gas igniter / flame sensor / gas valve path applies to gas dryers. Vent clearing applies to both.

Q: When should I replace a dryer instead of repairing it?

Replace the dryer when the total repair cost (parts + labor) crosses $200 and the unit is older than 8–10 years. As a rule of thumb, if the repair exceeds half the replacement cost, replacement wins. A new mid-range electric dryer runs $400–750 installed; a comparable gas dryer runs $450–800. If the failure is the control board on a modern electronic dryer (Samsung, LG, newer Whirlpool) — board replacement is $80–250 in parts and the board itself is the most expensive single component. Two failed boards on the same dryer, or a board failure on a unit with an otherwise worn drum belt / failing motor, is a strong signal to replace. Otherwise, repair almost always wins: the most common no-heat cause (blown thermal fuse) is a $15 fix with a screwdriver.

A dryer that tumbles but produces no heat is one of the most common appliance service calls. The drum spins, the timer runs, and clothes come out just as damp as they went in. The good news: in roughly 60–70% of cases, the fix is a $5–20 part and a screwdriver. The workflow is always symptom → vent → component — clear the vent first or you'll just be replacing fuses until something gives. The diagnostic below mirrors what an experienced tech actually walks on the call, in the order they walk it.

Safety first: Unplug the dryer from the wall before opening any panels or testing components. Electric dryers run on 240V — shock risk is serious. For gas dryers, also shut off the manual gas supply valve behind the unit before moving it or opening the burner access. If you smell gas at any point, ventilate, leave the building, and call the gas company from outside.

Match Your Symptom to a Likely Cause

Before pulling the dryer apart, match what you're seeing to the most likely component. The exact symptom tells you where to start — and where not to bother looking. Use the table below to skip ahead to the relevant step.

What you're seeing	Most likely cause	Start at step
Drum tumbles, no heat, exhaust air is cool	Blown thermal fuse or failed heating element (electric); failed igniter or flame sensor (gas)	Step 2
Drum tumbles, weak heat, clothes still damp after a full cycle	Cycling thermostat failing intermittently, restricted exhaust vent, or partially failed heating element	Step 5 + Step 4
Drum tumbles, no ignition sound (gas dryer), no flame	Failed igniter, flame sensor, or gas valve coil	Step 3
Dryer tumbles, then displays an error code or stops mid-cycle	Failed thermistor, control board relay, or sensor fault	Step 4
Takes 2+ cycles to dry a load, dryer feels hot to the touch outside	Restricted exhaust vent — root cause of most thermal-fuse failures	Step 5 first

Not all dryers present exactly like this — brand-specific quirks appear in Step 3 (electric vs. gas). If you're unsure whether your dryer is electric or gas, the FAQ below has a quick how-to.

Causes, Ranked by Frequency

Field-tech call data, in roughly the order the failure shows up on service tickets:

1

Blown thermal fuse (electric dryers)

The single most common cause on any electric dryer — roughly 40% of no-heat calls. A small one-time-use safety device on the exhaust duct. Trips to prevent overheating when the vent is restricted. Cannot be reset; must be replaced. Underlying cause is almost always a clogged vent — replace the fuse, then clear the vent, or the new fuse blows again.

2

Failed heating element (electric) or gas igniter / flame sensor (gas)

Second most common. The element is a coiled resistance wire that can burn out or develop a break in the coil. On gas dryers, the glow-bar igniter and the radiant flame sensor are the parallel failure points. Igniter should glow within 30–60 s of cycle start — glow with no flame = sensor or coils; no glow = igniter itself.

3

Restricted exhaust vent / clogged lint trap (root cause)

Not strictly a component failure — but it's the root cause behind most thermal-fuse and element failures. A duct packed with lint traps heat, the thermal fuse trips, and the next thermal event takes out a more expensive part. The U.S. Fire Administration attributes about 2,900 dryer fires per year to restricted exhaust.

4

Failed cycling thermostat or high-limit thermostat

The cycling thermostat regulates drum temperature by switching the element on and off; the high-limit is a one-time safety cutoff. Either fails open after years of cycling or from chronic overheating. Both bimetal, $10–25, testable with a multimeter at room temperature. On modern electronic dryers, the parallel component is the thermistor.

5

Failed thermistor or control board relay

Last-resort diagnosis, more common on newer electronic dryers (Samsung, LG, recent Whirlpool). The thermistor is a temperature-sensing resistor; the control board may have a failed heating relay. Board is model-specific ($80–250 in parts) and the failure is sometimes visible — burned relay contacts, swollen caps, scorch marks.

1

Confirm the Symptom Pattern

5-minute observation — free

DIY · $0

Before pulling anything apart, run the dryer for five minutes on a regular heat cycle and observe exactly what's happening. The drum-spinning-vs-not-spinning distinction routes the diagnostic to completely different components.

Drum spinning, exhaust cool or only slightly warm: Classic no-heat symptom. Drum motor and door switch are working; the failure is on the heat side. Proceed to Step 2.
Drum spinning, weak heat, clothes still damp after a full cycle: The heating circuit is partially working. Most often a clogged vent or a cycling thermostat failing intermittently. Proceed to Step 5 (vent) and Step 4 (thermostat/thermistor).
Gas dryer — drum spinning, no ignition sound: Igniter, flame sensor, or gas valve coils. Proceed to Step 3.
Drum not spinning at all: Not a heat issue. This is a belt, motor, door switch, or start capacitor problem — diagnose those separately.
Takes 2+ cycles to dry a load, dryer feels hot to the touch on the outside: Almost certainly a restricted exhaust vent. Go to Step 5 first.

Document the pattern. Write down the brand, model number (inside the door frame or on the back data plate), and whether it's electric or gas. Everything downstream is faster when you have those three facts.

✓ Confirm: Drum is spinning (or isn't) and the exhaust air is cool, warm, or hot. You've also noted the brand and model number before opening anything.

2

Test the Thermal Fuse (Electric Dryers)

Most common electric-dryer no-heat cause

DIY · $5–20

The thermal fuse is a small white or silver rectangle on the exhaust duct, just upstream of the blower outlet — two wire leads, two screws. It blows to prevent the dryer from overheating when the vent is restricted.

Unplug the dryer. Remove the back panel (4–8 screws around the perimeter).
Locate the fuse. On Whirlpool, Maytag, Kenmore, and GE dryers, it's on the exhaust duct near the blower outlet. LG and Samsung place it on the heater housing.
Disconnect both wire leads from the fuse terminals (pull on the spade connectors, not the wires).
Multimeter test. Set to continuity or Ω. Touch one probe to each terminal. A working fuse reads 0 Ω (or beeps). A blown fuse reads OL — open circuit.
If blown: replace with a model-specific fuse, cross-referenced by part number on the old fuse. $5–20 for the part.
Critical — don't skip Step 5. A blown fuse is a symptom, not the root cause. Clear the exhaust vent before reassembly or the new fuse will blow again within minutes.

Electrical safety: Never test components with the dryer plugged in. Element terminals carry 240V — shock risk is serious.

✓ Confirm: Fuse tests good (0 Ω) or has been replaced, AND vent (Step 5) cleared before reassembly.

3

Test the Heating Element (Electric) or Gas Igniter + Flame Sensor (Gas)

Branches based on electric vs. gas

DIY · $20–60 (electric) Tech Comfortable · $15–40 (gas)

If the thermal fuse tests good and the dryer still produces no heat, the actual heater is the next suspect. The diagnostic splits here — electric dryers use a coiled heating element, gas dryers use a glow-bar igniter with a flame sensor.

Electric dryers — heating element:

Locate the element. Whirlpool and Maytag top-loaders: back panel near the drum. Samsung and LG front-loaders: back or bottom. Check your service manual.
Disconnect both wire leads on the element terminals, then test for continuity with a multimeter on Ω. A working element reads 8–50 Ω (varies by wattage). An OL reading means the coil is broken.
Visually inspect. A burned element shows an obvious break in the coil or scorch marks on the housing.
Replace if failed. Match by model number. Held in with 2–4 screws; 30–60 minute swap. $20–60 for the part.

Gas dryers — igniter, flame sensor, gas valve coils:

Watch through the lower access panel as you start a heat cycle. The igniter (a fragile ceramic glow-bar) should glow within 30–60 seconds.
Glow but no flame: the flame sensor or gas valve coils have failed — replace the coil kit first ($10–30), it's cheaper than the sensor.
No glow at all: the igniter has burned out. Test for continuity (50–400 Ω). Replace $15–40.
Don't touch the glow element with bare hands — skin oils cause premature failure. Use clean gloves or a clean cloth.

Gas safety: Shut off the manual gas supply valve behind the dryer before any burner work. If you smell gas at any point, stop: do not operate switches or open flames. Ventilate, leave the building, and call the gas company from outside. Uncomfortable with gas-valve or burner work? Call a licensed tech — this is a hard line.

✓ Confirm: Electric: element reads 8–50 Ω with no visual damage (or has been replaced). Gas: igniter glows within 60 s, gas valve opens, flame stays lit for the full cycle.

4

Test the Cycling Thermostat, High-Limit, and Thermistor

Don't skip — these run hot after chronic vent restriction

DIY · $10–35

If the fuse and the element (or igniter) test good, the thermostat that regulates heat is next. Two thermostats are typical: the cycling thermostat (switches the element on and off) and the high-limit (a one-time safety cutoff). On modern electronic dryers, the parallel component is the thermistor.

Location: Both thermostats are on the exhaust duct or heater housing — small disc or oval-shaped with two wire leads. Similar to the thermal fuse but a different part number.
Continuity test at room temperature: Disconnect both leads, multimeter on Ω or continuity. Working: 0 Ω or beep. OL means the thermostat has failed open and is not conducting.
Thermistor on electronic dryers: Samsung, LG, and newer Whirlpool use a thermistor instead of a bimetal cycling thermostat. At room temperature, expect 4–10 kΩ across the terminals — exact spec is in the service sheet. OL or a wildly wrong reading = failed.
Replace as a kit. Cycling thermostat $10–25, thermistor $15–30, full kits $15–35. They fail from the same root cause as the thermal fuse (chronic overheating from a restricted vent) and tend to fail in clusters — replace the fuse and both thermostats together.

This approach mirrors how thermistor failures are diagnosed on refrigerators — the same sensor-class failure pattern at Refrigerator Not Cooling, Step 3. Same multimeter technique, same room-temp-first workflow.

✓ Confirm: Cycling thermostat reads 0 Ω at room temp. High-limit reads 0 Ω at room temp. Thermistor (if present) reads within model spec. All replaced as needed.

5

Clear the Exhaust Vent and Lint Trap (Mandatory)

Do this in addition to any component replacement

DIY · $0–40

A clogged vent is the root cause of most thermal-fuse failures and the leading cause of home clothes-dryer fires. Every dryer open for service should have the vent cleared before closing the panels back up.

Wash the lint screen with warm water and dish soap — fabric-softener sheets coat the mesh with an invisible film that progressively blocks airflow. Let it dry fully before reinstalling.
Test airflow at the dryer port. Disconnect the flex duct at the back and run the dryer for 30 seconds. You should feel strong warm airflow at the exhaust port. Weak or no airflow means the blower wheel or a downstream duct is obstructed.
Clean the duct run with a $20–40 brush kit from the hardware store. Push lint out from the dryer end or pull from the exterior cap. Most runs are 5–15 ft.
Check the exterior vent cap. Clean the flap and the screen (if present). A stuck flap blocks airflow on every cycle.
Inspect the duct material. Replace foil flex with rigid smooth metal where possible — foil flex that is kinked, crushed, or longer than 8 ft significantly restricts airflow. Smooth rigid metal moves air more efficiently and is far less flammable.
Confirm termination. The vent should terminate at the exterior wall with a backdraft damper. Never into a crawl space, attic, or interior wall cavity.

Fire hazard: The U.S. Fire Administration reports about 2,900 dryer fires per year, with failure to clean the dryer exhaust as the single leading cause. If the duct is packed hard with lint, treat this as a fire-safety project, not maintenance — replace foil flex with rigid metal and confirm exterior termination.

✓ Confirm: Lint screen clean and dry. Strong airflow at the dryer port. Duct run cleared. Exterior cap clean and flap free. Duct is rigid metal or smooth flexible (not crushed foil). Vent terminates exterior.

6

When to Suspect the Control Board or Relay

Last-resort diagnosis after everything else passes

Tech Recommended · $80–250

If all heating components test good and the vent is clear with strong airflow, the control board may have a failed relay on the heating circuit. Last-resort diagnosis for electronic dryers with digital controls (Samsung, LG, newer Whirlpool).

Look for visible board damage: Pull the control board access panel (usually under the top of the dryer or behind the rear panel). Inspect for burned relay contacts, scorch marks, or swollen capacitors. A visibly burned relay is diagnostic on its own.
Check error codes: many modern dryers display a fault code on the control panel when a board or sensor fault is detected. Look up the model in the service sheet. Thermistor open-circuits often show as a sensor fault rather than a heat fault.
Control board replacement cost: $80–250 depending on brand and model. At this cost, factor in unit age.
Replacement threshold: if the total repair (parts + labor if not DIY) exceeds $200 and the dryer is over 8–10 years old, replacement usually wins. A new mid-range electric runs $400–750 installed; gas is $450–800.
Two board failures on the same dryer, or a board failure on a unit with a worn drum belt and a failing motor, is a strong signal to replace.

✓ Confirm: Steps 1–5 all pass. Board shows visible damage or is the only remaining explanation. Unit age and total repair cost have been weighed against a replacement quote.

Repair Cost Estimates

Repair	Difficulty	Parts Cost	Total (w/ Labor)
Thermal fuse replacement	DIY	$5–$20	$80–$120
Heating element (electric)	DIY	$20–$60	$150–$250
Gas igniter (glow bar)	Tech	$15–$40	$130–$200
Gas valve solenoid coil kit	Tech	$10–$30	$100–$170
Cycling thermostat	DIY	$10–$25	$100–$160
Thermistor (electronic dryers)	DIY	$15–$30	$120–$180
Exhaust vent cleaning + brush kit	DIY	$0–$40	$75–$150
Control board replacement	Tech	$80–$250	$250–$400
New dryer replacement (replacement vs. repair decision)	Pro install	$400–$750	$400–$800

Labor rates vary by region. Most fuse and element swaps take under 30 minutes for an experienced technician. Board replacements run 45–90 minutes.

Field Walkthrough — FixAtlas Guiding a Homeowner

Here's how the FixAtlas AI walks a real homeowner through the diagnostic when the symptom matches a tumble-but-no-heat complaint. The exchange is condensed from an actual session.

Walkthrough — Dryer not heating

Homeowner: My dryer tumbles but nothing is getting dry — clothes are still damp after a full cycle.

FixAtlas: Has the dryer been getting worse over a few weeks, or did it stop heating suddenly?

Homeowner: Worse — first one extra cycle, now two.

FixAtlas: That's a vent-restriction pattern. When the exhaust can't escape, the thermal fuse trips to prevent overheating. Electric or gas?

Homeowner: Electric. Whirlpool, about 6 years old.

FixAtlas: Start with the thermal fuse. Unplug the dryer, remove the back panel, look for a small white rectangle on the exhaust duct near the blower outlet. Two leads, two screws. Pull the leads off and continuity-test it — 0 Ω is good, OL means blown.

Homeowner: Reads OL.

FixAtlas: Blown fuse, as expected. Replace it — but don't install it and reassemble yet. A new fuse in a still-restricted vent will blow again within minutes. Pull the flex duct off the back, run the dryer for 30 seconds, and tell me what you feel at the exhaust port.

Homeowner: Weak, not much air.

FixAtlas: Confirms it. Clean the duct run with a $25 brush kit, then clear the exterior vent cap. Once airflow is strong, install the new fuse ($5–$20 cross-referenced by part number).

Homeowner: And if the foil duct is crushed?

FixAtlas: Replace the foil flex with rigid smooth metal duct — about a 30-minute job. Rigid metal moves air roughly three times more efficiently than crushed foil and is far less flammable. Run this on your own dryer — just enter the brand and model and the AI walks the rest of the diagnostic in real time.

See this session condensed into a standalone homeowner walkthrough: FixAtlas Walks a Homeowner Through a Dryer Not Heating. For the full timestamped transcript — showing exactly when each AI decision point landed — see the Dryer Not Heating AI Transcript.

Frequently Asked Questions

Why is my dryer not heating?

Almost always one of four component failures: a blown thermal fuse (the most common electric-dryer cause), a failed heating element, a failed gas igniter or flame sensor (gas dryers), or a cycling thermostat failed open. A clogged vent is the root cause behind roughly half of thermal-fuse failures — always clear the vent before installing any replacement part. For the same component-class test pattern on a parallel appliance, see Refrigerator Not Cooling.

How do I test a dryer thermal fuse?

Unplug the dryer and pull the back panel. The fuse is a small white or silver rectangle on the exhaust duct near the blower outlet — two wire leads, two screws. Pull the leads off, set the multimeter to continuity (Ω), and touch one probe to each terminal. A working fuse reads 0 Ω (or beeps). A blown fuse reads OL — open circuit. Replace with a model-specific fuse ($5–20), but clear the vent first — a fuse that blows without a clogged vent usually means a failed cycling thermostat or restricted airflow.

Can a clogged dryer vent stop the dryer from heating?

Yes — and it almost always does eventually. A clogged vent is the root cause of most thermal-fuse failures: heat builds inside the drum, the fuse trips to prevent a fire, and the dryer stops heating. Clean the duct annually with a $20–40 brush kit and check the exterior cap. The U.S. Fire Administration attributes about 2,900 dryer fires per year to restricted exhaust — treat it as a fire-safety project, not just a maintenance fix. Full procedure is in Step 5.

What does it cost to fix a gas dryer that's not heating?

Three components dominate gas-dryer no-heat repairs: a glow-bar igniter ($15–40, 30–45 min DIY), a gas valve solenoid coil kit ($10–30, 20–30 min DIY), and a radiant flame sensor ($10–25, 20 min DIY). A tripped thermal fuse downstream of the burner runs $5–20. Professional service: $130–200 for most gas-dryer heating repairs. If the drum tumbles but no ignition sound is heard, the igniter is the leading suspect.

How do I tell if my dryer is electric or gas?

Look behind the dryer. Electric: thick 240V power cord on a 30A breaker plus a 4-inch metal exhaust duct. Gas: a standard 120V plug, the same exhaust duct, and a 1/2-inch flexible gas supply line with a manual shutoff valve. Gas dryers also have a small gas control valve and burner assembly behind the lower access panel — electric dryers don't. The diagnostic splits accordingly: Steps 2–4 cover electric, Step 3 has the gas branch, vent clearing applies to both.

When should I replace a dryer instead of repairing it?

Replace the dryer when total repair (parts + labor) crosses $200 and the unit is older than 8–10 years. Rule of thumb: if the repair exceeds half the replacement cost, replacement wins. A new mid-range dryer runs $400–750 installed (electric) or $450–800 (gas). Two failed boards on the same dryer, or a board failure on a unit with a worn belt and failing motor, is a strong signal to replace. Otherwise repair wins: the most common cause (blown thermal fuse) is a $15 fix. For the replace-vs-repair math on another appliance, see Washer Not Draining.